WO2012014591A1

WO2012014591A1 - Illumination apparatus, display apparatus, and television receiver apparatus

Info

Publication number: WO2012014591A1
Application number: PCT/JP2011/063707
Authority: WO
Inventors: 張　志芳
Original assignee: シャープ株式会社
Priority date: 2010-07-26
Filing date: 2011-06-15
Publication date: 2012-02-02

Abstract

The objective of the invention is to partially control the light emission status in an illumination apparatus and to achieve low cost. A backlight apparatus (12) according to the invention comprises a plurality of light guide members (19) each of which has a light incidence surface (19b) on which a light is incident and a light emergence surface (19a) from which the incident light is caused to emerge. The plurality of light guide members (19) are stacked in such a manner that the light emergence surfaces (19a) of the respective light guide members (19) are adjacent to each other in the depth direction viewed from the light incidence surfaces (19b) thereof. The backlight apparatus (12) further comprises: a plurality of LEDs (17) that are aligned along the stacking direction of the light guide members (19); a polygon mirror (22) that is rotated about an axis extending along the stacking direction of the light guide members (19), while reflecting lights from the LEDs (17) and using the reflected lights to scan the light incidence surfaces (19b); and a control unit (25) that controls the light emission statuses of the LEDs (17) in such a time division manner that the light emission statuses of the LEDs (17) are associated with scan periods of the respective reflected lights corresponding to a plurality of regions into which the light incidence surfaces (19b) are separated in the scan direction of the reflected lights from the polygon mirror (22).

Description

Lighting device, display device, and television receiver

The present invention relates to a lighting device, a display device, and a television receiver.

In recent years, the display elements of image display devices such as television receivers are shifting from conventional cathode ray tubes to thin display panels such as liquid crystal panels and plasma display panels, which enables thinning of image display devices. Since the liquid crystal panel used for the liquid crystal display device does not emit light by itself, a backlight device is separately required as a lighting device, and the backlight device is roughly classified into a direct type and an edge light type according to the mechanism. In order to further reduce the thickness of the liquid crystal display device, it is preferable to use an edge light type backlight device, and an example described in Patent Document 1 below is known.

JP 2001-92370 A

(Problems to be solved by the invention)
In the above-described Patent Document 1, a plurality of light sources arranged in parallel at the end of the backlight device and a light guide plate that guides light from the light sources and emits the light toward the liquid crystal panel side. The light guide plate is configured to extend along a direction orthogonal to the parallel direction of the light sources, and a plurality of light guide plates are arranged in parallel along the parallel direction of the light sources. However, in this case, although it is possible to control the light emission state between adjacent light guide plates, since the entire light guide plate emits light, light is partially emitted in the direction orthogonal to the parallel direction of the light sources. The state could not be controlled. In addition, in this case, since it is necessary to arrange a large number of light sources along the light incident surface, there is a problem that the cost of the light sources tends to increase. It was a problem.

The present invention has been completed based on the above situation, and aims to partially control the light emission state and reduce the cost.

(Means for solving problems)
The illumination device of the present invention has a light incident surface on which light is incident and a light emitting surface that emits the incident light, and the light emitting surfaces of each other are in the depth direction viewed from the light incident surface side. A plurality of light guide members arranged so as to be adjacent to each other, a plurality of light sources arranged side by side along the lamination direction of the light guide members, and an axis along the lamination direction of the light guide members A rotating reflector that reflects light from the light source while rotating around and scans the light incident surface with the reflected light, and a scanning direction by the reflected light from the rotating reflector on the light incident surface And a control unit that controls the light emission state of the light source in a time-sharing manner in association with a scanning period of the reflected light with respect to each region.

As described above, the plurality of light guide members are stacked so that the light emission surfaces thereof are adjacent to each other in the depth direction viewed from the light incident surface side, whereas the light sources are plural in the stacking direction of the light guide members. Each light source corresponding to each light guide member is arranged side by side and light from each light source corresponding to the stacking direction is incident on the light incident surface of each light guide member via the rotating reflector. By controlling this driving, it is possible to selectively control the amount of light emitted from each adjacent light exit surface of each light guide member.

In addition, the rotating reflector that reflects the light from the light source can be rotated around an axis along the stacking direction of the light guide member to scan the reflected light on the light incident surface. The scanning direction intersects the above-described arrangement direction of the adjacent light emitting surfaces. Then, the control unit controls the light emission state of the light source in a time-sharing manner in association with the scanning period of the reflected light with respect to each region on the light incident surface divided in the scanning direction by the reflected light from the rotating reflector. It is possible to selectively control the incident light amount of the reflected light with respect to each region and the emitted light amount from each region on the light emitting surface corresponding to each region of the light incident surface.

Therefore, the light emitting surface in the illumination device constituted by the set of the light emitting surfaces is a scanning of the light incident surface by the reflected light intersecting the alignment direction of the light emitting surfaces adjacent to each other and the alignment direction of the light emitting surfaces. It is possible to partially control the light emission amount for each of the divided areas while being divided in a matrix with respect to the direction. Moreover, according to the present invention, the number of light sources used can be reduced compared to a conventional arrangement in which a large number of light sources are arranged in parallel and the light emission state of each light source is adjusted individually. Costs related to the light source can be reduced.

The following configuration is preferable as an embodiment of the present invention.
(1) The number of the light guide members to be stacked and the number of the light sources arranged side by side in the stacking direction of the light guide members are the same. If it does in this way, since each light source can be individually matched and arranged with respect to each light guide member laminated, each light guide member corresponding by controlling individually the light emission state of each light source. The amount of light emitted from the light exit surface can be individually controlled.

(2) The alignment direction of the light source and the rotating reflector and the alignment direction of the rotating reflector and the light guide member are substantially orthogonal to each other. If it does in this way, compared with the case where a light source, a rotation reflector, and a light guide member are located in a line, the whole illuminating device can be kept small.

(3) The rotating reflector is disposed at a substantially central position of the light incident surface in the scanning direction. In this way, among the light reflected by the rotating reflector, the light path lengths of the light reaching one end of the light incident surface and the light reaching the other end in the scanning direction are substantially equal. Become. Therefore, for example, it is possible to obtain an effect that it is easy to set the scanning period of each region of the light incident surface by the reflected light from the rotating reflector.

(4) The light source is disposed on an end side of the light incident surface in the scanning direction. In this case, compared to a case where the light source is arranged on the center side of the light incident surface in the scanning direction, it is possible to obtain an effect such as easy connection of wiring to the light source.

(5) The plurality of regions on the light incident surface are partitioned so that the dimensions in the scanning direction are substantially the same. In this way, the scanning period of the reflected light from the rotating reflector with respect to each region of the light incident surface can be made substantially the same, so that the control by the control unit becomes easier.

(6) The rotating reflector is constituted by a polygon mirror that rotates in one direction. In this way, each region on the light incident surface can be scanned by the reflected light from the polygon mirror rotating in one direction, which is particularly suitable for scanning the light incident surface at high speed.

(7) The polygonal mirror has a regular polygonal shape when viewed from the direction along the rotation axis. In this way, the surfaces that reflect the light from the light source are all uniform in size. For example, if the rotation speed of the polygon mirror is constant, the scanning range for the light incident surface per unit time is constant. be able to.

(8) The polygon mirror has a square shape when viewed from the direction along the rotation axis. In this way, the angle range in which light from the light source can be reflected is approximately 180 degrees. Therefore, it is suitable particularly when the light incident surface of the light guide member is large in the scanning direction, and the degree of freedom of arrangement of the rotating reflector in the illumination device is increased.

(9) A condensing member that is interposed between the light source and the rotating reflector and condenses the light from the light source and emits the light toward the rotating reflector. In this way, the light emitted from the light source can be efficiently supplied to the rotating reflector. Thereby, the light from the light source can be incident on the light incident surface of the light guide member without waste, and the utilization efficiency can be improved, so that the luminance can be improved and the power consumption can be reduced.

(10) The light condensing member condenses light from the light source so that a traveling direction of light emitted toward the rotating reflector is parallel to the light incident surface. If it does in this way, it can be made to inject into each area | region in a light-incidence surface by reflecting and angling the light parallel to a light-incidence surface by a rotation reflector.

(11) The control unit blinks the light source periodically to change the time ratio between the lighting period and the extinguishing period. In this way, the light emission state of the light source is controlled by a so-called PWM (Pulse Width Modulation) method, so that the voltage value applied to the light source can be made constant, and the circuit configuration related to the control can be changed. It can be made simple, and a light control range can be secured sufficiently large, and the light emission state of the light source can be controlled more appropriately.

(12) The light guide member includes a plurality of divided light guide members divided for each of the plurality of regions on the light incident surface. If it does in this way, the light which injected into each area | region in a light-incidence surface can be made to radiate | emit, after being individually guided by each division | segmentation light guide member.

(13) A low refractive index layer having a refractive index relatively lower than that of the divided light guide member is interposed between the adjacent divided light guide members. If it does in this way, since it will become difficult to radiate | emit the light in a division | segmentation light guide member to the low-refractive-index layer side, it can prevent that light crosses between adjacent division | segmentation light guide members, and an adjacent division | segmentation light guide member The optical independence can be ensured. In addition, it is possible to secure a sufficient amount of light emitted from each divided light guide member and improve luminance.

(14) The plurality of light guide members to be stacked are arranged such that the light incident surfaces are flush with each other. If it does in this way, when laminating | stacking a some light guide member, positioning of each light guide member can be aimed at easily by aligning each light-incidence surface in the same shape, and it is excellent in workability | operativity.

(15) The rotating reflector has a reflecting surface that reflects light from the light source and can be parallel to the light incident surface, whereas a plurality of the light sources arranged along the stacking direction has the reflecting surface. They are arranged in a straight line parallel to the surface. According to this configuration, the light emitted from the light sources arranged in the stacking direction is reflected by the reflecting surface of the rotating reflector and then enters the light incident surfaces of the stacked light guide members. Can be made substantially equal for each light source. Thereby, it becomes easier to control the light emission state of each light source by the control unit.

(16) The light guide member has a bottom surface located on the opposite side of the light emitting surface and parallel to the light emitting surface. In this way, in comparison with the case where the light emitting surface and the bottom surface are not parallel and the light guide member is tapered, the same as when the light guide member is stacked in the correct order when the lighting device is manufactured. It is possible to obtain an effect such that it is easy to distinguish when the stacking order is wrong, and the strength is also excellent.

(17) The plurality of light guide members to be stacked include a first light guide member relatively disposed on a light output side and a light output side relatively to the first light guide member. At least a second light guide member disposed on the opposite side, and the second light guide member has a support surface that supports the bottom surface of the first light guide member, and the support surface includes On the other hand, it has the said light-projection surface in the form adjacent to the depth direction seen from the said light-incidence surface side. In this way, the first light guide member can be stably supported by the support surface, and the workability when the first light guide member is stacked on the second light guide member during manufacturing is excellent. Since it is avoided that the first light guide member is laminated on the light exit surface of the second light guide member, light from the light exit surface can be emitted without passing through the first light guide member. .

(18) The second light guide member is provided with a protruding light output portion that has the light output surface and protrudes further toward the light output side than the support surface. If it does in this way, since it is set as the form which a protrusion light-emitting part protrudes in the light-projection side rather than a support surface, it has the light-projection surface in a 1st light guide member, and the protrusion light-projection part in a 2nd light guide member It is possible to reduce or eliminate the step between the light exit surface. Thereby, for example, the stability when the other member (such as an optical member) is placed on the light exit surface is excellent, and the optical path length from when the light exits each light exit surface to the other member described above is improved. The difference can be mitigated or eliminated.

(19) The protruding light exit portion of the second light guide member is formed such that the light exit surface thereof is flush with the light exit surface of the first light guide member. If it does in this way, a level difference can be eliminated between the light emission surface which the 1st light guide member has, and the light emission surface which the projection light emission part in the 2nd light guide member has. Thereby, for example, when the other member is placed on the light exit surface, the stability is extremely excellent, and the difference in the optical path length from when the light exits each light exit surface to the other member described above is eliminated. be able to.

(20) A portion of the bottom surface of the second light guide member that overlaps with the protruding light output portion when seen in a plane rises toward the light emission side in a depth direction viewed from the light incident surface side. An inclined surface having such a gradient is formed. In this case, the light exit surface of the second light guide member is relatively far from the light entrance surface in the depth direction as compared to the light exit surface of the first light guide member. Although it is relatively inferior in terms of light utilization efficiency in guiding the light incident on the incident surface to the light exit surface and emitting it, an inclined surface is formed on the portion of the bottom surface that overlaps the protruding light output portion having the light exit surface. Thus, the internal light can be efficiently launched toward the light exit surface. Thereby, the utilization efficiency of the light in the 2nd light guide member can be improved, and it can be made hard to produce a difference in the utilization efficiency of light between the 1st light guide member.

(21) In the plurality of light guide members to be stacked, the areas of the light emitting surfaces adjacent to each other are substantially equal. This makes it easy to control the drive of each light source in adjusting the brightness per unit area in the light emitted from each light exit surface.

(22) The plurality of light guide members to be stacked have the same dimension in the scanning direction. In this way, when laminating a plurality of light guide members, if the end faces in the scanning direction are aligned with each other, the light guide members can be laminated over the entire area in the scanning direction. Therefore, each light guide member can be easily positioned and the workability is excellent.

(23) The light guide member has a bottom surface located on the side opposite to the light emitting surface, and is provided with a reflective member that is disposed along the bottom surface and reflects light. If it does in this way, light can be efficiently propagated in a light guide member by reflecting the light in a light guide member with a reflection member, and light can be raised toward a light-projection surface. .

(24) The reflection member covers a surface of the light guide member opposite to the light incident surface. If it does in this way, it can prevent that the light which propagates the inside of a light guide member radiate | emits from the surface on the opposite side to the light-incidence surface in a light guide member, and can improve the utilization efficiency of light more. .

(25) The light source is an LED. In this way, high brightness and low power consumption can be achieved.

Next, in order to solve the above problem, a display device of the present invention includes the above-described illumination device and a display panel that performs display using light from the illumination device.

According to such a display device, the lighting device that supplies light to the display panel can partially control the light emission state and reduce the number of light sources used, thereby improving display quality. It is possible to reduce the manufacturing cost and the like.

A liquid crystal panel can be exemplified as the display panel. Such a display device can be applied as a liquid crystal display device to various uses such as a display of a television or a personal computer, and is particularly suitable for a large screen.

(The invention's effect)
According to the present invention, it is possible to partially control the light emission state and reduce the cost.

1 is an exploded perspective view showing a schematic configuration of a television receiver according to Embodiment 1 of the present invention. The exploded perspective view which shows schematic structure of the liquid crystal display device with which a television receiver is equipped The top view which shows the arrangement structure of the chassis in the backlight apparatus with which a liquid crystal display device is equipped, the light guide member, and the light source unit. Sectional view taken along line iv-iv in FIG. V-v sectional view of FIG. Block diagram for explaining LED drive control The top view for demonstrating operation | movement of a light source unit, Comprising: The reflected light injects into the 1st division | segmentation light incident surface The top view for demonstrating operation | movement of a light source unit, Comprising: The reflected light injects into the 3rd division | segmentation light incident surface The top view for demonstrating operation | movement of a light source unit, Comprising: The reflected light injects into the 6th division | segmentation light entrance surface The top view for demonstrating operation | movement of a light source unit, Comprising: The reflected light injects into the 8th division | segmentation light incident surface The top view for demonstrating operation | movement of a light source unit, Comprising: The reflected light is irradiated to the synchronous detection part An enlarged plan view for explaining an operation of the light source unit and showing a process in which the reflected light scans the fourth split light incident surface. Sectional drawing which shows the cross-sectional structure of the light guide member in the backlight apparatus which concerns on Embodiment 2 of this invention. Sectional drawing which shows the case where a structure is changed so that an optical member may be laminated | stacked directly on the light-projection surface of a light guide member The top view which shows the arrangement configuration of the chassis in the backlight apparatus which concerns on Embodiment 3 of this invention, a light guide member, and a light source unit. Xvi-xvi sectional view of FIG. The top view which shows the arrangement configuration of the chassis in the backlight apparatus which concerns on Embodiment 4 of this invention, a light guide member, and a light source unit. Xviii-xviii sectional view of FIG. Xix-xix cross-sectional view of FIG. The top view which shows the arrangement configuration of the chassis in the backlight apparatus which concerns on Embodiment 5 of this invention, a light guide member, and a light source unit. Xxi-xxi sectional view of FIG. The top view which shows the arrangement configuration of the chassis in the backlight apparatus which concerns on Embodiment 6 of this invention, a light guide member, and a light source unit. The top view which shows the arrangement configuration of the light source unit which concerns on Embodiment 7 of this invention. The top view which shows the arrangement configuration of the chassis in the backlight apparatus which concerns on other embodiment (1) of this invention, a light guide member, and a light source unit. The top view which shows the arrangement configuration of the light source unit which concerns on other embodiment (2) of this invention.

<Embodiment 1>
A first embodiment of the present invention will be described with reference to FIGS. In this embodiment, the liquid crystal display device 10 is illustrated. In addition, a part of each drawing shows an X axis, a Y axis, and a Z axis, and each axis direction is drawn to be a direction shown in each drawing. Moreover, let the upper side shown in FIG.4 and FIG.5 be a front side, and let the lower side of the figure be a back side.

As shown in FIG. 1, the television receiver TV according to the present embodiment includes a liquid crystal display device 10, front and back cabinets Ca and Cb that are accommodated so as to sandwich the liquid crystal display device 10, a power source P, a tuner T, And a stand S. The liquid crystal display device (display device) 10 has a horizontally long (longitudinal) square shape as a whole and is accommodated in a vertically placed state. As shown in FIG. 2, the liquid crystal display device 10 includes a liquid crystal panel 11 that is a display panel and a backlight device (illumination device) 12 that is an external light source, which are integrated by a frame-like bezel 13 or the like. Is supposed to be retained.

As shown in FIG. 2, the liquid crystal panel 11 has a horizontally long (longitudinal) rectangular shape in a plan view, and a pair of glass substrates are bonded together with a predetermined gap therebetween, and between the two glass substrates. The liquid crystal is sealed. One glass substrate is provided with a switching element (for example, TFT) connected to a source wiring and a gate wiring orthogonal to each other, a pixel electrode connected to the switching element, an alignment film, and the like. The substrate is provided with a color filter and counter electrodes in which colored portions such as R (red), G (green), and B (blue) are arranged in a predetermined arrangement, and an alignment film. The liquid crystal panel 11 is connected to a control board (not shown) with a liquid crystal driving driver for supplying a driving signal to each source wiring and each gate wiring. The driving is controlled by the liquid crystal panel control unit 26 (FIG. 6). The liquid crystal panel control unit 26 displays, for example, 60 or 120 display images per second on the liquid crystal panel 11. A polarizing plate is disposed on the outside of both substrates.

As shown in FIG. 2, the backlight device 12 covers a substantially box-shaped chassis 14 having an opening that opens toward the light emission surface side (the liquid crystal panel 11 side), and covers the opening of the chassis 14. The optical member 15 group (diffusing plate (light diffusing member) 15a and a plurality of optical sheets 15b arranged between the diffusing plate 15a and the liquid crystal panel 11) is provided. Further, in the chassis 14, a light source unit U, which will be described in detail later, a light guide member 19 that guides light from the light source unit U and guides it to the optical member 15 (liquid crystal panel 11), the optical member 15, and the liquid crystal. A frame 16 that receives the panel 11 from the back side is provided. The backlight device 12 is of a so-called edge light type (side light type) in which the light source unit U is arranged opposite to one end of the light guide member 19 on the long side. Below, each component of the backlight apparatus 12 is demonstrated in detail.

The chassis 14 is made of a metal plate material (sheet metal made of iron, aluminum, or the like). As shown in FIGS. 2 and 3, the chassis 14 has a horizontally long bottom plate 14a and a length of the bottom plate 14a. It is comprised from a pair of side plate 14b of the long side which stands | starts up from each outer end of a side, and a pair of side plate 14c of the short side which stands up from each outer end of the short side in the baseplate 14a. The long side direction of the chassis 14 (bottom plate 14a) coincides with the X-axis direction (horizontal direction), and the short side direction coincides with the Y-axis direction (vertical direction). The frame 16 and the bezel 13 can be screwed to the long side plate 14b.

As shown in FIG. 2, the optical member 15 has a horizontally long rectangular shape when viewed in a plane, like the liquid crystal panel 11 and the chassis 14. The optical member 15 is placed between the liquid crystal panel 11 and the light guide member 19 by being placed on the front side (light emitting side) of the frame 16. The optical member 15 includes a diffusion plate 15a disposed on the back side (light guide member 19 side, opposite to the light emitting side) and an optical sheet 15b disposed on the front side (liquid crystal panel 11 side, light emitting side). Composed. The diffusing plate 15a has a structure in which a large number of diffusing particles are dispersed in a substantially transparent resin-made base material having a predetermined thickness, and has a function of diffusing transmitted light. The optical sheet 15b has a sheet shape that is thinner than the diffusion plate 15a, and three optical sheets are laminated. Specific types of the optical sheet 15b include, for example, a diffusion sheet, a lens sheet, a reflective polarizing sheet, and the like, which can be appropriately selected and used.

As shown in FIGS. 4 and 5, the frame 16 is formed in a frame shape (frame shape) extending along the outer peripheral end of the chassis 14, and is external to the

side plates

14 b and 14 c of the chassis 14. It can be fitted. The frame 16 has two stepped receiving surfaces. The optical member 15 is received from the lower receiving surface shown in FIGS. 4 and 5, and the liquid crystal panel 11 is received from the rear side from the upper receiving surface. It is supposed to be possible. Of the pair of long side portions of the frame-like portion of the frame 16, the long side portion on the light source unit U side (left side shown in FIG. 4) is more than the other long side portion as shown in FIG. Is also formed wide. As for the bezel 13, the long side portion on the light source unit U side has a wide shape like the above-described frame 16 (FIGS. 2 and 4).

Subsequently, after describing the light guide member 19 first, the light source unit U will be described. The light guide member 19 is made of a synthetic resin material (for example, acrylic) having a refractive index sufficiently higher than that of air and substantially transparent (exceeding translucency). As shown in FIGS. 2 and 3, the light guide member 19 according to the present embodiment is formed in a plate shape that has a horizontally long rectangular shape in a plan view as with the liquid crystal panel 11 and the chassis 14 as a whole. The long-side direction is the X-axis direction, the entire short-side direction is the Y-axis direction, and the thickness direction perpendicular to the main plate surface is the Z-axis direction. As shown in FIG. 4, a plurality of (four) light guide members 19 are arranged in a position immediately below the liquid crystal panel 11 and the optical member 15 in the chassis 14, and one end of the light guide member 19 group. The light source unit U is arranged to face the portion (lower end portion shown in FIG. 3). Accordingly, the alignment direction of the light source unit U and the light guide member 19 matches the Y-axis direction, while the alignment direction of the optical member 15 (liquid crystal panel 11) and the light guide member 19 matches the Z-axis direction. Both the alignment directions are orthogonal to each other. The light guide member 19 introduces light from the LED 17 included in the light source unit U, and has a function of rising and emitting the light toward the optical member 15 side (Z-axis direction) while propagating the light inside. . In the backlight device 12 according to the present embodiment, four types of light guide members 19 having different sizes and the like are stacked and used. Hereinafter, the common structure of each light guide member 19 will be described first, A different structure of each light guide member 19 will be described.

First, the common structure of the light guide member 19 will be described. As shown in FIGS. 3 and 4, the light guide member 19 has a substantially flat plate shape that extends along the bottom plate 14 a of the chassis 14 and the plate surfaces of the optical member 15 as a whole. It is assumed to be parallel to the axial direction and the Y-axis direction. Of the main plate surface of the light guide member 19, the surface facing the front side (light emitting side) and facing the optical member 15, that is, the portion exposed to the optical member 15 side, transmits the internal light to the optical member 15 (liquid crystal The light emission surface 19a is emitted toward the panel 11). Of the outer peripheral end surfaces adjacent to the main plate surface in the light guide member 19, the lower side (left side in FIG. 4) end surface shown in FIG. 3 facing the light source unit U on the long side, that is, in the light guide member 19. An end surface of the end portion on the light source unit U side is a light incident surface 19b on which light from the light source unit U is incident. The light incident surface 19b as a whole is a long surface in which the long side direction coincides with the X-axis direction and the short side direction coincides with the Z-axis direction, and is a surface substantially orthogonal to the light emitting surface 19a. The

As shown in FIG. 4, of the main plate surface of the light guide member 19, the surface opposite to the light exit surface 19 a (back side) is a bottom surface 19 c, and the reflection sheet 20 is arranged along the bottom surface 19 c. ing. The reflection sheet 20 is made of a synthetic resin having a white surface with excellent light reflectivity, covers the entire bottom surface 19 c of the light guide member 19, and is the light incident surface 19 b of the light guide member 19. The end opposite to the LED 17 side is bent so as to cover the surface 19d on the opposite side. The light guide member 19 has a substantially constant plate thickness dimension (dimension in the Z-axis direction) over the entire region, and therefore, the light emitting surface 19a and the bottom surface 19c described above are parallel to each other without crossing each other. Is done.

At least one of the light exit surface 19a of each light guide member 19 and the portion of the bottom surface 19c that overlaps the light exit surface 19a in plan view, a reflecting portion (not shown) that reflects internal light. Alternatively, a scattering portion (not shown) that scatters internal light is patterned to have a predetermined in-plane distribution. The light propagating through the light guide member 19 is reflected by the reflecting portion or scattered by the scattering portion, and is thus urged to be emitted from the light emitting surface 19a to the outside. For example, the in-plane distribution of the reflection part or the scattering part has a lower distribution density toward the side closer to the light source unit U and a higher distribution density toward the side farther from the light source unit U. Thereby, the light emitted from the light emitting surface 19a is controlled to have a uniform distribution in the surface.

As shown in FIG. 4, the light guide member 19 having the above-described common structure is different from the backlight device 12 according to the present embodiment in four types having different sizes in a plan view as shown in FIG. Direction) is used in a stacked form. Furthermore, as shown in FIGS. 3 and 5, the four types of light guide members 19 to be stacked are each divided into eight in the X-axis direction (width direction), and accordingly, the light incident surface 19a and The light exit surface 19b and the like are also divided into eight. Hereinafter, the different structures of the four types of light guide members 19 to be stacked and the divided structure of the light guide members 19 will be described in detail in order.

First, the different structures of the four types of light guide members 19 to be stacked will be described in detail. In the following description, when distinguishing the laminated light guide members 19, the one arranged most on the front side is referred to as a “first light guide member”, and the subscript A is arranged on the reference symbol second and from the front side. Is the second light guide member, and the subscript B is the third from the front side. The third light guide member is the third light guide member, and the subscript C is the fourth from the front side (most back). In the case where what is arranged is a “fourth light guide member” and a subscript D is added to the code and is generically referred to without distinction, the subscript is not added to the code. Further, the subscripts A to D described above are also attached when distinguishing the related portions (specifically, the light emitting surface 19a, the light incident surface 19b, the bottom surface 19c, etc.) of each light guide member 19.

As shown in FIGS. 3 to 5, the four types of light guide members 19A to 19D have the same overall length in the long side direction (X-axis direction), that is, the long side dimensions are the same. Regarding the dimension in the short side direction (Y-axis direction), that is, the short side dimension, the front side (light emission side) gradually decreases stepwise, and the back side (opposite side to the light emission side) gradually decreases. It is said that it tends to increase gradually. Specifically, the second light guide member 19B, the third light guide member 19C, and the fourth light guide member 19D disposed on the back side of the first light guide member 19A have the short side dimensions and the main plate surfaces (the bottom surfaces 19cB to 19cB). 19cD) is an integer multiple of the short side dimension of the first light guide member 19A and the area of the main plate surface (bottom surface 19cA). More specifically, the second light guide member 19B is laminated immediately behind the first light guide member 19A, and the short side dimension and the area of the main plate surface (bottom surface 19cB) are the first light guide member 19A. It is about twice as large. The third light guide member 19C is laminated immediately behind the second light guide member 19B, and the short side dimension and the area of the main plate surface (bottom surface 19cC) are about 1.5 times that of the second light guide member 19B. And about 3 times the size of the first light guide member 19A. The fourth light guide member 19D is laminated immediately behind the third light guide member 19C, and the short side dimension and the area of the main plate surface (bottom surface 19cD) are about 1.3 times that of the third light guide member 19B. And about twice as large as the second light guide member 19B, and about four times as large as the first light guide member 19A. Thus, the short side dimensions and the area of the main plate surface (bottom surfaces 19cB to 19cD) in the second light guide member 19B to the fourth light guide member 19D, and the first light guide members 19A to 3A stacked immediately on the front side thereof. The difference between the short side dimension of the light guide member 19C and the area of the main plate surface (bottom surfaces 19cA to 19cC) is substantially the same, and the size thereof is the short side dimension of the first light guide member 19A and the main plate surface (bottom surface 19cA). ).

Of the four types of light guide members 19A to 19D stacked on each other, for the first light guide member 19A arranged on the front side, the light emitting surface where the entire area of the main plate surface facing the front side is exposed to the optical member 15 side. 19aA, the second light guide member 19B to the fourth light guide member 19D stacked on the back side of the first light guide member 19A to the third light guide member 19C are arranged on the main plate surface facing the front side. The first light guide member 19A to the third light guide member 19C, which are partially laminated on the front side, are used as support surfaces 19e that support the light guide surfaces 19eB. 19aD. The support surface 19e forms a continuous plane together with the light emitting surface 19a adjacent in the Y-axis direction. In the following description, when the support surfaces 19e of the second light guide member 19B to the fourth light guide member 19D are distinguished, the corresponding subscripts B to D are respectively attached, and are collectively referred to without distinction. Shall not be subscripted.

In the four types of light guide members 19A to 19D stacked on each other, the light incident surfaces 19b are all flush with each other, and both end faces along the entire short side direction are all flush with each other. ing. That is, the light guide members 19A to 19D having different short side dimensions are arranged to be offset toward the light source unit U side. Accordingly, among the main plate surfaces facing the front side in the second light guide member 19B to the fourth light guide member 19D, the predetermined region on the side opposite to the light source unit U side is on the front side, and the first light guide member 19A to the third light guide is on the front side. The light emitting surfaces 19aB to 19aD on which the member 19C is not stacked are provided, whereas the predetermined regions on the light source unit U side are the support surfaces 19eB to 19eD on which the first light guide member 19A to the third light guide member 19C are stacked on the front side. It is said. As described above, the support surfaces 19eB to 19eD are arranged between the light emitting surfaces 19aB to 19aD of the second light guide member 19B to the fourth light guide member 19D and the light source unit U. . That is, the second light guide member 19B to the fourth light guide member 19D have the light emission surfaces 19aB to 19aD in such a manner that the support surfaces 19eB to 19eD are sandwiched between the light source unit U. In other words, the light exit surfaces 19aB to 19aD of the second light guide member 19B to the fourth light guide member 19D are in the depth direction as seen from the light incident surfaces 19bB to 19bD that are flush with each other (shown in FIG. 3). The upper side and the right side in FIG. In the second light guide member 19B to the fourth light guide member 19D, the entire short side direction (Y-axis direction) and the alignment direction of the support surfaces 19eB to 19eD and the light emission surfaces 19aB to 19aD are the same. The direction from the support surfaces 19eB to 19eD toward the light exit surfaces 19aB to 19aD (upward in FIG. 3, right in FIG. 4) coincides with the direction away from the light source unit U (light incident surfaces 19bB to 19bD). The direction from the emission surfaces 19aB to 19aD toward the support surfaces 19eB to 19eD (the lower side in FIG. 3 and the left side in FIG. 4) coincides with the direction approaching the light source unit U (light incident surfaces 19bB to 19bD).

The support surfaces 19eB to 19eD of the second light guide member 19B to the fourth light guide member 19D are the bottom surfaces 19cA to 19cA to 19C of the first light guide member 19A to the third light guide member 19C stacked on the front side to be supported. It has the same area as 19cC. In other words, the light output surfaces 19aB to 19aD of the second light guide member 19B to the fourth light guide member 19D have the first light guide member 19A stacked on the front side to be supported from the area of the main plate surface facing the front side. The area of the third light guide member 19C is obtained by subtracting the area of the bottom surfaces 19cA to 19cC. Specifically, in the second light guide member 19B, about half of the main plate surface facing the front side opposite to the light source unit U is the light emitting surface 19aB, whereas the second light guide member 19B is on the light source unit U side. The half of the area is a support surface 19eB that supports the first light guide member 19A. In the third light guide member 19C, about 1/3 of the main plate surface facing the front side opposite to the light source unit U is the light emitting surface 19aC, while the second light guide member 19C has about 2 on the light source unit U side. The region of / 3 is a support surface 19eC that supports the second light guide member 19B. The fourth light guide member 19D has a light emitting surface 19aD in which about 1/4 of the main plate surface facing the front side opposite to the light source unit U is the light emitting surface 19aD. The region of / 4 is a support surface 19eD that supports the third light guide member 19C. The areas of the bottom surfaces 19cB to 19cD forming the main plate surfaces of the second light guide member 19B to the fourth light guide member 19D are the sum of the areas of the light exit surfaces 19aB to 19aD and the areas of the support surfaces 19eB to 19eD, respectively. It is assumed to be equal to the size.

As shown in FIG. 4, the support surfaces 19eB to 19eD of the second light guide member 19B to the fourth light guide member 19D are stacked on the front side, as shown in FIG. Are substantially entirely covered by the reflection sheets 20 arranged along the bottom surfaces 19cA to 19cC. Thereby, the light propagating through the second light guide member 19B to the fourth light guide member 19D, which is relatively arranged on the back side (arranged on the lower stage side shown in FIGS. 4 and 5), is emitted from the light emitting surface 19aB. Preventing entry into the first light guide member 19A to the third light guide member 19C stacked on the front side (arranged on the upper side shown in FIGS. 4 and 5) before reaching 19aD it can. Therefore, optical independence between the light guide members 19A to 19D stacked on each other can be ensured. The second light guide member 19B to the fourth light guide member 19D form a light guide unit in which the portion having the support surfaces 19eB to 19eD guides the light from the light source unit U toward the light emission surfaces 19aB to 19aD. In other words, it can be said that the portion having the light emitting surfaces 19aB to 19aD forms a light emitting portion that emits light.

When the first light guide member 19A to the third light guide member 19C are stacked on the support surfaces 19eB to 19eD of the second light guide member 19B to the fourth light guide member 19D having the above-described configuration when viewed in plan. As shown in FIG. 3, the light source unit U, the light output surface 19aA of the first light guide member 19A, the light output surface 19aB of the second light guide member 19B, and the light output of the third light guide member 19C from the lower side of FIG. The surface 19aC and the light exit surface 19aD of the fourth light guide member 19D are arranged in this order along the Y-axis direction. The light emission surface 19aA of the first light guide member 19A arranged on the front side is closest to the light source unit U, and the light emission surface 19aD of the fourth light guide member 19D arranged on the back side is farthest from the light source unit U. It is supposed to be arranged. In other words, the light emitting surfaces 19aA to 19aC of the light guide members 19A to 19C relatively disposed on the front side are relatively closer to the light source unit U, and the light output of the light guide members 19B to 19D relatively disposed on the back side. The surfaces 19aB to 19aD are arranged relatively far from the light source unit U. When the state in which the light guide members 19A to 19D are stacked is viewed in a cross section along the Y-axis direction, as shown in FIG. 4, each of the light emission surfaces 19aA to 19aD has a stepped shape. The level difference between 19aA to 19aD is approximately equal to the thickness of each light guide member 19. The light emitting surfaces 19aA to 19aC of the light guide members 19A to 19C relatively arranged on the front side are relatively closer to the optical member 15 and the light emission of the light guide members 19B to 19D relatively arranged on the back side. The surfaces 19aB to 19aD are disposed relatively far from the optical member 15.

Subsequently, the divided structure of the light guide member 19 will be described in detail. Hereinafter, the divided light guide member 19 is referred to as a “divided light guide member”, and the divided light incident surface 19 a and the light output surface 19 b are referred to as “divided light incident surface” and “divided light output”. It is assumed that a suffix “S” is added to each symbol. As shown in FIGS. 3 and 5, each divided light guide member 19 S has a shape in which the light guide member 19 is divided along the short side direction (Y-axis direction) and the long side direction (X-axis direction). The divided width (dimension along the scanning direction to be described later) is substantially equal. Each divided light guide member 19 S has a long side dimension that coincides with an overall short side dimension of the light guide member 19, whereas a short side dimension (a dimension along a scanning direction described later) has a light guide member 19. About 1/8 of the entire long side dimension. There is a slight gap between the adjacent divided light guide members 19S, and this is an air layer (low refractive index layer) AS having a relatively lower refractive index than each divided light guide member 19S. . This air layer AS prevents the light propagating through the interior between the adjacent divided light guide members 19S from leaking, thereby ensuring optical independence between the adjacent divided light guide members 19S. The light emitting surface 19a and the light incident surface 19b are divided into a plurality of regions for each divided light guide member 19S in the X-axis direction, and the divided regions are divided light emitting surfaces 19aS and divided light incident surfaces 19bS. It is said. In other words, each divided light guide member 19S has a divided light emitting surface 19aS and a divided light incident surface 19bS individually, and each divided light emitting surface 19aS adjacent in the X-axis direction is arranged in a flush manner. As a result, the entire light emitting surface 19a of the light guide member 19 is configured, and the divided light incident surfaces 19bS adjacent to each other in the X-axis direction are arranged in a flush manner, so that the entire light guide member 19 is arranged. The light incident surface 19b is configured. The divided light exit surfaces 19aS have substantially the same area. Similarly, the divided light incident surfaces 19bS have substantially the same area.

In the following, when distinguishing each divided light guide member 19S, each divided light emitting surface 19aS, and each divided light incident surface 19bS, the one at the left end shown in FIG. 3 (the one closest to the LED 17) is “first”. The subscript “A” is attached to each symbol, and the right side of the symbol is designated as “second”, “third”..., And the subscript “B”, “C”,. Each of the symbols is attached with a suffix “H” as “eighth” with the one at the right end of the figure (the one farthest from the LED 17). Specifically, the first divided light guide member 19SA to the eighth divided light guide member 19SH respectively include the first divided light incident surface 19aSA to the eighth divided light incident surface 19aSH and the first divided light output surface 19bSA to the eighth. Each has a divided light exit surface 19bSH. In addition, when each division | segmentation light guide member 19S, each division | segmentation light emission surface 19aS, and each division | segmentation light entrance surface 19bS are named generically without distinguishing, a subscript shall not be attached | subjected to each code | symbol.

Subsequently, the light source unit U will be described in detail. 2 and 3, the light source unit U emits an LED (Light Emitting Diode) 17 as a light source, an LED substrate 18 on which the LED 17 is mounted, and the light from the LED 17 while condensing the light. A condenser lens 21 to be reflected, a polygon mirror 22 that reflects light from the condenser lens 21 toward the light guide member 19, and a synchronization detection unit 23 that synchronizes the light emission state of the LED 17 with the rotation state of the polygon mirror 22. It is composed of

The LED 17 has a configuration in which an LED chip is sealed with a resin material on a substrate portion fixed to the LED substrate 18 as shown in FIG. The LED chip mounted on the substrate unit has one main emission wavelength, and specifically, one that emits blue light in a single color is used. On the other hand, the resin material that seals the LED chip is dispersed and blended with a phosphor that emits a predetermined color when excited by the blue light emitted from the LED chip, and generally emits white light as a whole. It is said. In addition, as the phosphor, for example, a yellow phosphor that emits yellow light, a green phosphor that emits green light, and a red phosphor that emits red light are used in appropriate combination, or any one of them is used. It can be used alone. The LED 17 is a so-called top type in which a surface opposite to the mounting surface with respect to the LED substrate 18 is a light emitting surface. The LED 17 has a light distribution such that the optical axis of the emitted light, that is, the traveling direction of light having the highest emission intensity coincides with the X-axis direction.

The LED substrate 18 has a plate shape made of synthetic resin (such as glass epoxy resin), and has a white surface with excellent light reflectivity. As shown in FIG. 3, the LED board 18 has its main plate surface parallel to the Y-axis direction and the Z-axis direction, that is, orthogonal to the main plate surfaces of the liquid crystal panel 11 and the light guide member 19 (optical member 15). It is accommodated in the chassis 14 in a posture. The LED board 18 is fixed to the left side plate 14b shown in FIG. 3 among the side plates 14c on the short side of the chassis 14 by screws or the like. The LED substrate 18 is disposed at a position spaced apart from the light incident surface 19b of the light guide member 19 in the side plate 14c on the short side. A wiring pattern (not shown) made of a metal film (copper foil or the like) is formed on the mounting surface of the LED 17 on the LED substrate 18, and terminal portions formed at the ends of the wiring pattern will be described later. By being connected to the external LED driving unit 24, driving power is supplied to the LED 17. In addition, by attaching the LED board 18 to the side plate 14c arranged at the end of the chassis 14, it is possible to easily secure a wiring path to the LED driving unit 24.

As shown in FIGS. 4 and 5, the LED substrate 18 has a dimension in the Z-axis direction that is substantially equal to the sum of the thicknesses of the four light guide members 19A to 19D stacked on each other. Has been. Then, four LEDs 17 are arranged side by side in the Z-axis direction, that is, in the stacking direction of the light guide members 19, and the number of the LEDs 17 is equal to the number of the light guide members 19 stacked. . In the following description, when distinguishing the four LEDs 17 arranged in the Z-axis direction, the one arranged most on the front side is referred to as “first LED”, and the subscript A is arranged on the code second and from the front side. "Second LED" with the subscript B in the code, the third one from the front side, "third LED" with the subscript C in the code, the fourth from the front side (most back side) When the subscript D is added to the reference sign as “fourth LED” and the reference is made without distinction, the reference sign is not added. The four LEDs 17A to 17D are arranged at positions corresponding individually to the stacked four light guide members 19A to 19D in the Z-axis direction. Specifically, the first LED 17A is the first light guide member 19A, the second LED 17B is the second light guide member 19B, the third LED 17C is the third light guide member 19C, and the fourth LED 17D is the fourth light guide member 19D. It is arranged in a one-to-one correspondence with respect to the direction. These four LEDs 17A to 17D are arranged at substantially the center position in the Z-axis direction of the corresponding light guide members 19A to 19D, and the interval between adjacent LEDs 17, that is, the arrangement pitch of the LEDs 17A to 17D, is It almost coincides with the plate thickness dimension of the light guide members 19A to 19D. The four LEDs 17A to 17D are linearly aligned along the Z-axis direction without being shifted from each other in the Y-axis direction, and the arrangement direction is parallel to the light incident surface 19b. Accordingly, the intervals between the LEDs 17A to 17D arranged along the Z-axis direction and the condenser lens 21 described below are all equal, and further, the intervals between the LEDs 17A to 17D and the polygon mirror 22 are set. Are all equal.

As shown in FIG. 3, the condenser lens 21 is interposed between the LED 17 and a polygon mirror 22 described below, and is disposed relatively closer to the LED 17 than the polygon mirror 22. Specifically, the condensing lens 21 is arranged at a position facing the first divided light incident surface 19bSA of the first divided light guide member 19SA closest to the LED 17 among the light guide members 19 with a predetermined interval. Has been. The condensing lens 21 as a whole is formed in a semi-doughnut shape in plan view, and the surface on the LED 17 side (surface on the light incident side) forms a concave curved surface and the surface on the polygon mirror 22 side (light emission). Side surface) is a convex curved surface. The condensing lens 21 can emit the light emitted from the LED 17 while condensing the light, and the emitted light travels substantially straight along the X-axis direction (parallel to the light incident surface 19b). At the same time, the optical design is such that it hits the polygon mirror 22. Specifically, the light emitted from the LED 17 includes light that travels in a direction inclined with respect to the optical axis, in addition to the light having the highest emission intensity that travels along the X-axis direction, which is the optical axis. There are a lot of components having a component in the Y-axis direction or the Z-axis direction. However, light that travels in a direction inclined with respect to the optical axis is refracted or reflected in the process of passing through the condenser lens 21. By doing so, it can be converted into light that travels substantially straight along the optical axis (X-axis direction) and strikes the polygon mirror 22 without having a component in the Y-axis direction or the Z-axis direction. As a result, the light emitted from the four LEDs 17A to 17D arranged along the Z-axis direction goes straight along the X-axis direction and does not cross each other in the Z-axis direction. Is to be reflected by. Of the light emitted from the LED 17, the light having the highest emission intensity that travels along the X-axis direction, which is the optical axis, is hardly affected by refraction even when transmitted through the condenser lens 21. It is assumed that the lens travels straight along the optical axis as it is.

As shown in FIG. 3, the polygon mirror 22 has an X-axis direction with respect to the condenser lens 21, that is, in the traveling direction of the emitted light from the condenser lens 21, more than the distance between the condenser lens 21 and the LED 17. They are placed at relatively wide positions. That is, the polygon mirror 22 is arranged linearly along the X-axis direction with respect to the LED 17 and the condenser lens 21. The polygon mirror 22 is disposed at a substantially central position with respect to the light guide member 19 in the entire long side direction (the parallel direction of the divided light guide members 19S, the X-axis direction). The polygon mirror 22 has a rotation axis 22a along the Z-axis direction, that is, the stacking direction of the light guide member 19, and has a reflection surface 22b that reflects light from the condenser lens 21 on the outer peripheral surface thereof. The light incident surface 19b of the light guide member 19 can be scanned with the reflected light by reflecting the light from the condensing lens 21 by the reflecting surface 22b while rotating around the rotation axis 22a in one direction. The As shown in FIGS. 4 and 5, the polygon mirror 22 has substantially the same dimension in the Z-axis direction as the sum of the thicknesses of the four light guide members 19A to 19D stacked on each other. The dimensions of the LED substrate 18 in the Z-axis direction are almost the same. Therefore, the reflection surface 22b of the polygon mirror 22 reflects the light emitted from the four LEDs 17A to 17D arranged along the Z-axis direction and irradiated through the condenser lens 21, and each light guide member 19A. It is possible to individually scan the light incident surfaces 19bA to 19bD of 19 to 19D.

Specifically, as shown in FIGS. 3 to 5, the polygon mirror 22 has a prismatic shape having a square planar shape when viewed from the direction along the rotation axis 22 a (Z-axis direction) as a whole. Four flat reflective surfaces 22b are formed adjacent to each other on the surface. The reflecting surfaces 22b are equal in area and dimensions. The angle formed by the adjacent reflecting surfaces 22b is 90 degrees. Since each reflecting surface 22b is a substantially straight surface along the Z-axis direction (the direction in which the light guide members 19 are stacked and the direction in which the LEDs 17 are arranged), depending on the rotational position of the polygon mirror 22, the light incident surface 19b or the LED substrate 18 is used. The LED 17 can be mounted in parallel with the mounting surface of the LEDs 17 (alignment direction of the LEDs 17A to 17D) (FIG. 3). Accordingly, the light reflected by each reflecting surface 22b travels straight along the plane direction along the X-axis direction and the Y-axis direction, and has almost no component in the Z-axis direction. Thereby, the light emitted from the four LEDs 17A to 17D arranged along the Z-axis direction and reflected by the reflecting surface 22b via the condenser lens 21 does not intersect in the Z-axis direction. The light guide members 19A to 19D corresponding to the directions are individually incident. Accordingly, the light emitted from the first LED 17A enters the light incident surface 19bA of the first light guide member 19A via the condenser lens 21 and the polygon mirror 22, and then selectively exits from the light emitting surface 19aA. The lowermost ¼ region shown in FIG. 3 is in charge of the entire light emitting surface of the backlight device 12. Similarly, the light emitted from the second LED 17B is selectively emitted from the light emission surface 19aB of the second light guide member 19B, and is the second one from the lower side shown in FIG. / 4 area. The light emitted from the third LED 17C is selectively emitted from the light emission surface 19aC of the third light guide member 19C, and is the second quarter from the upper side shown in FIG. You will be in charge of the area. The light emitted from the fourth LED 17D is selectively emitted from the light emitting surface 19aD of the fourth light guide member 19D, and the uppermost ¼ region shown in FIG. I will be in charge.

As shown in FIG. 3, the polygon mirror 22 is driven by an electromagnetic motor (not shown) to rotate around the rotation axis 22a in the clockwise direction (arrow direction) shown in FIG. It is rotated at a speed (angular speed). As the polygon mirror 22 rotates, the angle of each reflecting surface 22b with respect to the light from the condenser lens 21 toward the polygon mirror 22 changes in a time-division manner, and the light reflected by the reflecting surface 22b The traveling direction changes in a time-sharing manner. Specifically, since the polygonal mirror 22 has a square planar shape, the traveling direction of the light (reflected light) reflected by the reflecting surface 22 b is the traveling direction of the light from the condenser lens 21 toward the polygon mirror 22. The angle formed with respect to the angle can be changed in the range of 0 to 180 degrees (angle range of 180 degrees). Accordingly, the reflected light from the polygon mirror 22 is directed from the left side to the right side shown in FIG. 3 along the long side direction (X-axis direction) of the light incident surface 19b of the light guide member 19 as the polygon mirror 22 rotates. It is possible to scan linearly. Specifically, the reflected light is transmitted from the left end shown in FIG. 3 on the first light incident surface 19bSA of the first divided light guide member 19SA to FIG. 3 on the eighth light incident surface 19bSH of the eighth divided light guide member 19SH. It can be continuously scanned over the entire area up to the right end shown. The rotation speed of the polygon mirror 22 is such that the time it takes for the reflected light to scan from the left end of the first light incident surface 19bSA shown in FIG. 3 to the right end of the eighth light incident surface 19bSH shown in FIG. The display period of one display image on the panel 11 is set to coincide with, for example, 1/60 seconds, 1/120 seconds, or the like. Further, the time for scanning the divided light incident surface 19bS of each divided light guide member 19S with reflected light (one scanning period of reflected light with respect to the divided light incident surface 19bS) is the display period of one display image on the liquid crystal panel 11 ( For example, about 1/8 of 1/60 seconds, 1/120 seconds, etc.). The polygon mirror 22 and the light guide member 19 are arranged along the Y-axis direction, and the arrangement direction is orthogonal to the X-axis direction that is the arrangement direction of the LED 17, the condenser lens 21, and the polygon mirror 22. There is a relationship.

As shown in FIG. 3, the synchronization detection unit 23 is attached to the side plate 14 c of the chassis 14 to which the LED board 18 is attached. The synchronization detection unit 23 is located between the LED substrate 18 and the light guide member 19 and can receive the reflected light from the polygon mirror 22. The synchronization detection unit 23 has a built-in optical sensor (not shown) that can detect light, and can detect reflected light from the polygon mirror 22. The synchronization detection unit 23 is connected to a control unit 25 described below, and can output a detection signal toward the control unit 25 when detecting reflected light from the polygon mirror 22. Subsequently, drive control of the control unit 25 and the LED 17 will be described in detail.

As shown in FIG. 6, the control unit 25 can output a signal to the LED drive unit 24 based on the detection signal from the synchronization detection unit 23 to control the drive of each LED 17. Specifically, when the detection signal is input from the synchronization detection unit 23, the control unit 25 refers to information on the rotation speed of the polygon mirror 22 and outputs a signal related to the control to the LED drive unit 24 to obtain a predetermined signal. The light emission state of each LED 17 can be controlled at the timing. At this time, the control unit 25 can control the light emission state of each LED 17 in a time-sharing manner for each scanning period with respect to each divided light incident surface 19bS by reflected light. The control unit 25 can individually control the light emission states of the first LED 17A to the fourth LED 17D. Hereinafter, a specific control method of the light emission state of each LED 17 by the control unit 25 will be described in detail.

Specifically, the control unit 25 changes the time ratio between the lighting period and the extinguishing period by periodically blinking the LED 17 while keeping the voltage value applied to each LED 17 constant, so-called PWM (Pulse Width Modulation: The light emission state of each LED 17 is controlled by a (pulse width modulation) method, and the time ratio between the lighting period and the extinguishing period in one scanning period with respect to the divided light incident surface 19bS by reflected light is set to each divided light incident surface 19bS. Can be set individually for each scanning period. Note that the amount of incident light on the split light incident surface 19bS during the one scanning period is uniquely determined by the time ratio between the lighting period and the extinguishing period because the voltage value applied to each LED 17 is constant. The Therefore, the control unit 25 can freely set the amount of incident light on each divided light incident surface 19bS individually. For example, the amount of incident light on each divided light incident surface 19bS can be all the same or different. it can.

The control unit 25 receives a signal related to a display image from a liquid crystal panel control unit 26 that controls driving of the liquid crystal panel 11. Therefore, the control unit 25 can control the light emission state of each LED 17 based on the luminance information of the display image. Specifically, first, as shown in FIG. 3, the light emitting surfaces of the backlight device 12 as a whole according to the present embodiment are shared by the light emitting surfaces 19aA to 19aD of the four stacked light guide members 19A to 19D. Matrix with four regions in the Y-axis direction and eight regions in the X-axis direction shared by the divided light emitting surfaces 19aSA to 19aSH of the divided light guide members 19S constituting the light guide members 19A to 19D It is divided into 32 areas. Correspondingly, the control unit 25 divides the display image on the liquid crystal panel 11 into 32 divided display areas corresponding to the 32 areas constituting the light emitting surface, and signals related to the display image. From the calculated luminance information, the light emission states of the four LEDs 17A to 17D arranged in the Z-axis direction are independently driven based on the calculated luminance information, and the LEDs 17A to 17A The light emission state of 17D is controlled by time division for each scanning period with respect to each divided light incident surface 19bS.

This embodiment has the structure as described above, and its operation will be described next. In order to manufacture the liquid crystal display device 10, the separately manufactured liquid crystal panel 11, backlight device 12, bezel 13 and the like are assembled. Hereinafter, the manufacturing procedure of the backlight device 12 will be mainly described.

First, while the LED substrate 18 in which each LED 17 is mounted in the chassis 14, the condenser lens 21, the polygon mirror 22, and the synchronization detection unit 23 are respectively housed, the respective guides each integrating the reflection sheet 20 are performed. The operation | work which accommodates the optical member 19 is performed. When the light guide member 19 is attached, as shown in FIG. 4, the work of attaching the fourth light guide member 19D to the bottom plate 14a of the chassis 14 is performed in advance, and then the third light guide member 19C is attached to the fourth light guide member. It is placed and stacked on the support surface 19eD of 19D. Thereafter, the second light guide member 19B is placed on the support surface 19eC of the third light guide member 19C, and the first light guide member 19A is placed on the support surface 19eB of the second light guide member 19B. The assembly of the four light guide members 19A to 19D stacked on each other is completed. Since each light guide member 19A to 19D is divided into eight divided light guide members 19S, each divided light guide member 19S constituting each light guide member 19A to 19D is actually arranged in the X-axis direction. The above-described mounting operation is performed by sequentially stacking them in the Z-axis direction while arranging them (FIGS. 3 and 5).

Here, the main plate surfaces facing the front side in the second light guide member 19B to the fourth light guide member 19D arranged on the back side are the respective ones in the first light guide member 19A to the third light guide member 19C laminated on the front side. Since the area of each light emitting surface 19aB to 19aD is larger than that of the bottom surfaces 19cA to 19cC, the work of placing the first light guide member 19A to the third light guide member 19C can be easily performed. it can. In addition, the bottom surfaces 19cA to 19cC of the first light guide member 19A to the third light guide member 19C and the support surfaces 19eB to 19eD of the second light guide members 19B to 19D arranged on the back side are parallel to each other. Because of the relationship, the first light guide member 19A to the third light guide member 19C can be stably supported. Further, when the operator makes a mistake in the stacking order of the light guide members 19A to 19D, the light guide member 19 erroneously arranged on the front side is supported by the light guide member 19 erroneously arranged on the back side. Since the unsupported part is generated, the support state becomes unstable, and the unsupported part is easily lifted, so it is easy for the operator to make a mistake in the stacking order. You can notice. That is, it is possible to easily discriminate between the case where the stacking order of the light guide members 19A to 19D is correct and the case where the stacking order of the light guide members 19A to 19D is incorrect, so that the stacking order remains incorrect. It is possible to more surely prevent the product from being shipped. Further, when performing the above-described laminating operation of the light guide members 19, the light incident surfaces 19bA to 19bD of the light guide members 19A to 19D are aligned with each other, and in the Y-axis direction of the divided light guide members 19S. The both side end faces are aligned with each other.

When the attachment work of each light guide member 19 is completed, the frame 16 is attached to the chassis 14, and the optical members 15 and the liquid crystal panel 11 are sequentially mounted on the frame 16. Thereafter, the liquid crystal display device 10 is manufactured by attaching the bezel 13. When the power of the liquid crystal display device 10 manufactured as described above is turned on, the liquid crystal panel control unit 26 controls the driving of the liquid crystal panel 11 and the light from the light source unit U is transmitted to each light guide member 19. The light is incident on the light incident surface 19b, propagates through the inside thereof, and is emitted toward the liquid crystal panel 11 by being emitted from the light emitting surface 19a while being raised toward the optical member 15, and thus the liquid crystal panel 11 is irradiated with a predetermined amount. Is displayed. Hereinafter, the operation of the backlight device 12 will be described in detail.

When the power is turned on, each LED 17 is turned on by the LED drive unit 25 based on a signal from the control unit 25 constituting the light source unit U (FIG. 6), and the polygon motor 22 is driven by driving the electromagnetic motor. Is rotated around the rotation axis 22a at a constant rotation speed. Specifically, as shown in FIG. 3, the light from each of the LEDs 17A to 17D is condensed by the condenser lens 21, so that it does not have components in the Y-axis direction and the Z-axis direction and extends along the X-axis direction. After being emitted toward the polygon mirror 22 as light that travels straight forward, the light strikes the reflecting surface 22b of the polygon mirror 22, and a predetermined angle is given in the plane direction along the X-axis direction and the Y-axis direction. Reflected by. Here, since the light reflected by the reflection surface 22b of the polygon mirror 22 does not have a component in the Z-axis direction, the light emitted from the LEDs 17A to 17D arranged along the Z-axis direction is reflected by the reflection surface 22b. Even if they are reflected, they do not cross each other in the Z-axis direction, and are individually incident on the light guide members 19A to 19D corresponding to the Z-axis direction. Note that the optical path lengths until the light emitted from the LEDs 17A to 17D reaches the light incident surfaces 19bA to 19bD of the light guide members 19A to 19D are all equal.

The reflected light from the polygon mirror 22 can scan the light incident surfaces 19bA to 19bD of the light guide members 19A to 19D over the entire length in the X-axis direction. Specifically, as shown in FIGS. 7 to 10, the reflected light from the polygon mirror 22 scanned from the left end to the right end of the first divided light incident surface 19bSA of the first divided light guide member 19SA. Thereafter, the second divided light incident surface 19bSB of the second divided light guide member 19SB on the right side, the third divided light incident surface 19bSC... Of the third divided light guide member 19SC are scanned in this order, and the eighth divided light guide is obtained. After the eighth divided light incident surface 19bSH of the optical member 19SH is scanned, the first divided light incident surface 19bSA of the first divided light guide member 19SA is scanned again. Note that the time required for scanning all the divided light incident surfaces 19bS by reflected light by setting the rotational speed of the polygon mirror 22 is the display period of one display image on the liquid crystal panel 11 (for example, 1/60 seconds). , 1/120 seconds, etc.). The light emission states of the LEDs 17A to 17D are controlled by the control unit 25 so as to be synchronized with the rotation state of the polygon mirror 22 and the display image displayed on the liquid crystal panel 11.

Specifically, the light reflected by the reflecting surface 22b of the polygon mirror 22 includes what is irradiated on the synchronization detecting unit 23 as shown in FIG. 11 in addition to the light incident on the light incident surface 19b. Therefore, based on the detection of the reflected light from the polygon mirror 22 by the synchronization detection unit 23 and the output of the detection signal to the control unit 25, the control unit 25 changes the rotation state of the polygon mirror 22. The light emission states of the LEDs 17A to 17D can be synchronized. That is, the control unit 25 determines the light incident surface 19bA of each of the light guide members 19A to 19D by the reflected light of the polygon mirror 22 from the timing at which the detection signal is received from the synchronization detection unit 23 and the information about the rotation speed of the polygon mirror 22. Since the scanning position with respect to .about.19bD can be accurately calculated, the light emission state of each of the LEDs 17A to 17D can be controlled in a time-sharing manner for each scanning period in which the reflected light scans each divided light incident surface 19bS. is there. As shown in FIG. 12, this scanning period means the divided light from the scanning start position (indicated by the one-dot chain line in FIG. 12) where the reflected light is applied to the left end of the divided light incident surface 19bS of the divided light guide member 19S. This is the time required to reach the scanning end position (indicated by the two-dot chain line in the figure) irradiated on the right end of the figure on the incident surface 19bS. In the control unit 25, it is preferable to perform control such that the LEDs 17A to 17D are turned off during a period in which the reflected light can scan the air layer AS existing between the divided light incident surfaces 19bS.

Then, as shown in FIG. 6, the control unit 25 controls the light emission states of the LEDs 17A to 17D based on a signal related to the display image from the liquid crystal panel control unit 26 that controls the driving of the liquid crystal panel 11. . Specifically, the control unit 25 determines the Y-axis direction shared by the light emitting surfaces 19aA to 19aD of the stacked four light guide members 19A to 19D from the signal related to the display image input from the liquid crystal panel 11. And the eight regions in the X-axis direction shared by the divided light exit surfaces 19aSA to 19aSH of the divided light guide members 19S constituting the light guide members 19A to 19D. The luminance required for the 32 divided display areas is calculated, and based on the calculated luminance information, the light emission states of the four LEDs 17A to 17D arranged in the Z-axis direction are independently driven, and each LED 17A is driven. The light emission states of ˜17D are controlled in a time-sharing manner for each scanning period with respect to each divided light incident surface 19bS (see FIG. 3).

The specific drive control of each of the LEDs 17A to 17D will be described. The control unit 25 determines the time ratio between the lighting period and the extinguishing period of each LED 17A to 17D for each scanning period with respect to each divided light incident surface 19bS. The LED 17 is driven and controlled in a time-sharing manner while being determined based on the luminance information of the display area. For example, in the scanning period of the divided light incident surface 19bS of the divided light guide member 19S having the divided light emitting surface 19bS in the light emitting surfaces 19aA to 19aD sharing the relatively dark segmented display region, the lighting period is relatively short. In contrast, the incident light quantity is relatively reduced by extending the light extinction period, while the divided light guide member 19S having the divided light emitting surfaces 19bS in the light emitting surfaces 19aA to 19aD sharing the relatively bright divided display areas. Regarding the scanning period of the split light incident surface 19bS, the light emission states of the LEDs 17A to 17D are time-divided for each scanning period so that the incident light quantity is relatively increased by relatively lengthening the lighting period and shortening the extinguishing period. And control it. Thus, the amount of incident light on the divided light incident surface 19bS of each of the 32 divided light guiding members 19S constituting each of the light guiding members 19A to 19D can be individually adjusted, and the amount of incident light can be adjusted for the display image. It can be appropriate based on the luminance information.

The light incident on each split light incident surface 19bS is reflected by the reflection sheet 20 or totally reflected at the interface with the air layer AS, so that each split light guide can be efficiently performed without leaking to the outside. After propagating through the member 19S, the light is emitted from the split light exit surface 19aS. And the emitted light from each divided light emitting surface 19aS is applied to each divided display area in the liquid crystal panel 11, while the emitted light quantity is substantially equal to the incident light quantity to each divided light incident surface 19bS. Because of this relationship, the contrast ratio of the display image can be increased.

Specifically, in the first light guide member 19A, as shown in FIG. 4, since the entire area of the main plate surface facing the front side is the light emitting surface 19aA, the light propagating inside is raised by the reflection sheet 20 And is reflected by the reflecting portion or scattered by the scattering portion, so that the incident angle with respect to the light emitting surface 19aA becomes smaller than the critical angle, and most of the light is emitted from the light emitting surface 19aA to the front side outside. Is emitted. On the other hand, for the second light guide member 19B to the fourth light guide member 19D, the first light guide member 19A to the third light guide in which the region on the light source unit U side of the main plate surface facing the front side is laminated on the front side. Since the support surfaces 19eB to 19eD that support the member 19C are used, the light propagating through the inside reflects the reflection sheets 20 of the first light guide member 19A to the third light guide member 19C covering the support surfaces 19eB to 19eD, and the bottom surface. The light reaches the light exit surfaces 19aB to 19aD while being repeatedly reflected between the reflection sheets 20 arranged on 19cB to 19cD. In this process, the second light guide member 19B to the fourth light guide member 19D and the first light guide member 19A to the third light guide member 19C stacked on the front side are partitioned by the reflection sheet 20. It is avoided that light passes between each other. The light that has propagated through the second light guide member 19B to the fourth light guide member 19D and reached the light exit surfaces 19aB to 19aD side is the same as that of the first light guide member 19A described above, and the light exit surfaces 19aB to 19aD. To the outside of the front side. In addition, since the surface 19d opposite to the light incident surface 19b in each light guide member 19 is covered with the reflection sheet 20, it is possible to prevent the light from leaking from the surface 19d to the outside. Thus, light is guided to the light exit surface 19a.

As described above, the backlight device (illumination device) 12 of the present embodiment has the light incident surface 19b on which light is incident and the light emitting surface 19a for emitting the incident light, and the light emitting surfaces of each other. A plurality of light guide members 19 arranged so as to be adjacent to each other in the depth direction as viewed from the light incident surface 19b side, and a plurality arranged side by side along the direction in which the light guide members 19 are laminated. A polygon mirror that reflects light from the LED 17 while being rotated (rotated) around an axis along the stacking direction of the LED (light source) 17 and the light guide member 19, and scans the light incident surface 19b with the reflected light ( When the rotating reflector) 22 and the light incident surface 19b are divided into a plurality of regions (divided light incident surface 19bS) in the scanning direction (X-axis direction) by the reflected light from the polygon mirror 22, the reflected light to each region And a control unit 25 for dividing and controlled during the light emission state of the LED17 in association with the scanning period.

As described above, the plurality of light guide members 19 are stacked such that the light emission surfaces 19a are adjacent to each other in the depth direction viewed from the light incident surface 19b side, whereas the LEDs 17 are A plurality of light guide members 19 are arranged side by side in the stacking direction, and light from each LED 17 corresponding to the stacking direction is incident on the light incident surface 19 b of each light guide member 19 through the polygon mirror 22. By controlling the driving of each LED 17 corresponding to 19, the amount of light emitted from each adjacent light emitting surface 19a in each light guide member 19 can be selectively controlled.

In addition, the polygon mirror 22 that reflects the light from the LED 17 can be rotated around an axis along the stacking direction of the light guide member 19 to scan the reflected light on the light incident surface 19b. The scanning direction intersects with the arrangement direction of the adjacent light emitting surfaces 19a described above. Then, the control unit 25 controls the light emission state of the LED 17 in a time-sharing manner in association with the scanning period of the reflected light with respect to each region on the light incident surface 19b divided in the scanning direction by the reflected light from the polygon mirror 22. Thus, it is possible to selectively control the incident light amount of the reflected light to each region and the emitted light amount from each region on the light emitting surface 19a corresponding to each region of the light incident surface 19b.

Therefore, the light emitting surface in the backlight device 12 configured by the set of the light emitting surfaces 19a is in the arrangement direction of the light emitting surfaces 19a adjacent to each other (Y-axis direction) and the arrangement direction of the light emitting surfaces 19a. With respect to the scanning direction (X-axis direction) of the light incident surface 19b by the reflected light that intersects, the light emission amount can be partially controlled for each of the divided regions. Moreover, according to the present embodiment, the number of LEDs 17 used can be reduced compared to a conventional arrangement in which a large number of LEDs are arranged in parallel and the light emission state of each LED is individually adjusted. For example, the cost related to the LED 17 can be reduced.

Further, the number of the light guide members 19 to be laminated matches the number of the LEDs 17 arranged along the direction in which the light guide members 19 are laminated. If it does in this way, since each LED17 can be individually matched and arranged with respect to each light guide member 19 laminated, each light guide corresponding to each light guide state can be controlled by individually controlling the light emission state of each LED17. The amount of light emitted from the light exit surface 19a of the member 19 can be individually controlled.

Further, the arrangement direction of the LEDs 17 and the polygon mirror 22 (X-axis direction) and the arrangement direction of the polygon mirror 22 and the light guide member 19 (Y-axis direction) are substantially orthogonal to each other. In this way, the entire backlight device 12 can be kept small as compared with the case where the LED, the polygon mirror, and the light guide member are arranged in a straight line.

Further, the polygon mirror 22 is disposed at a substantially central position of the light incident surface 19b in the scanning direction. In this way, of the light reflected by the polygon mirror 22, the light path lengths of the light reaching one end of the light incident surface 19 b and the light reaching the other end in the scanning direction are substantially equal. Become. Therefore, for example, it is possible to obtain an effect that it is easy to set the scanning period of each region of the light incident surface 19 b by the reflected light from the polygon mirror 22.

The LED 17 is disposed on the end side of the light incident surface 19b in the scanning direction. In this way, compared to the case where the LED is arranged on the center side of the light incident surface 19b in the scanning direction, it is possible to obtain an effect such as easy connection of the wiring to the LED 17, for example.

Further, the plurality of regions on the light incident surface 19b are divided so that the dimensions in the scanning direction are substantially the same. In this way, the scanning period of the reflected light from the polygon mirror 22 for each region of the light incident surface 19b can be made substantially the same, so that the control by the control unit 25 becomes easier.

Further, the rotating reflector is constituted by a polygon mirror 22 that rotates in one direction. In this way, each region on the light incident surface 19b can be scanned by the reflected light from the polygon mirror 22 rotating in one direction, which is particularly suitable for scanning the light incident surface 19b at a high speed.

The polygon mirror 22 has a regular polygonal shape when viewed from the direction along the rotation axis 22a. In this way, the surfaces that reflect the light from the LED 17 are all uniform in size. For example, if the rotational speed of the polygon mirror 22 is constant, the scanning range for the light incident surface 19b per unit time is constant. It can be.

Further, the polygonal mirror 22 has a square shape when viewed from the direction along the rotation axis 22a. In this way, the angle range in which the light from the LED 17 can be reflected is approximately 180 degrees. Therefore, it is suitable particularly when the light incident surface 19b of the light guide member 19 is large in the scanning direction, and the degree of freedom of arrangement in the polygon mirror 22 in the backlight device 12 is increased.

Further, a condensing lens (condensing member) 22 is provided between the LED 17 and the polygon mirror 22 and condenses the light from the LED 17 and emits the light toward the polygon mirror 22. In this way, the light emitted from the LED 17 can be efficiently supplied to the polygon mirror 22. As a result, the light from the LED 17 can be incident on the light incident surface 19b of the light guide member 19 without waste, and the utilization efficiency can be improved. Therefore, the luminance can be improved and the power consumption can be reduced. it can.

The condensing lens 22 condenses the light from the LED 17 so that the traveling direction of the light emitted toward the polygon mirror 22 is parallel to the light incident surface 19b. In this way, the light parallel to the light incident surface 19b is reflected by the polygon mirror 22 and angled, so that it can be incident on each region on the light incident surface 19b.

Further, the control unit 25 periodically blinks the LED 17 to change the time ratio between the lighting period and the extinguishing period. Thus, since the light emission state of the LED 17 is controlled by a so-called PWM (Pulse Width Modulation) method, the voltage value applied to the LED 17 can be made constant, and a circuit configuration related to the control can be obtained. It can be made simple, and the dimming range can be secured sufficiently large, and the light emission state of the LED 17 can be controlled more appropriately.

The light guide member 19 is composed of a plurality of divided light guide members 19S divided into a plurality of regions on the light incident surface 19b. If it does in this way, the light which injected into each area | region in the light-incidence surface 19b can be radiate | emitted after light-guided separately by each division | segmentation light guide member 19S.

Further, a low refractive index layer having a refractive index relatively lower than that of the divided light guide member 19S is interposed between the adjacent divided light guide members 19S. This makes it difficult for the light in the divided light guide member 19S to be emitted to the low refractive index layer side, so that the light can be prevented from passing between the adjacent divided light guide members 19S, and the adjacent divided light guide member 19S can be prevented. The optical independence of the optical member 19S can be ensured. In addition, it is possible to secure a sufficient amount of light emitted from each divided light guide member 19S and improve luminance.

Further, the light guide members 19 to be stacked are arranged so that the light incident surfaces 19b are flush with each other. In this way, when the light guide members 19 are stacked, the light incident surfaces 19b are aligned so that the light guide members 19 can be easily positioned, thereby improving workability. Excellent.

The polygon mirror 22 has a reflection surface 22b that reflects the light from the LED 17 and can be parallel to the light incident surface 19b, whereas the plurality of LEDs 17 arranged along the stacking direction are parallel to the reflection surface 22b. They are arranged in a straight line. In this way, the light emitted from the LEDs 17 arranged in the stacking direction is reflected by the reflecting surface 22b of the polygon mirror 22, and then enters the light incident surfaces 19b of the stacked light guide members 19. The optical path length until this can be made substantially equal for each LED 17. Thereby, it becomes easier to control the light emission state of each LED 17 by the control unit 25.

The light guide member 19 has a bottom surface 19c located on the opposite side of the light emitting surface 19a and parallel to the light emitting surface 19a. In this way, the order in which the light guide members 19 are stacked at the time of manufacturing the backlight device 12 is correct in comparison with the case where the light exit surface and the bottom surface are not parallel and the light guide member 19 is tapered. It is possible to obtain an effect that it is easy to discriminate between the time and the case where the stacking order is wrong, and the strength is also excellent.

Further, the plurality of light guide members 19 to be stacked are relatively relative to the first light guide member 19A (the second light guide member 19B and the third light guide member 19C) disposed on the light emitting side. At least a second light guide member 19B (a third light guide member 19C and a fourth light guide member 19D) disposed on the side opposite to the light emitting side with respect to the first light guide member 19A is included. 2 The light guide member 19B has a support surface 19eB (support surface 19eC, support surface 19eD) that supports the bottom surface 19cA (the bottom surface 19cB, the bottom surface 19cC) of the first light guide member 19A, and the support surface 19eB The light exit surface 19aB (light exit surface 19aC, light exit surface 19aD) is adjacent to the depth direction viewed from the light incident surface 19b side. In this way, the first light guide member 19A can be stably supported by the support surface 19eB, and workability when the first light guide member 19A is stacked on the second light guide member 19B during manufacturing. In addition, since the first light guide member 19A can be avoided from being laminated on the light output surface 19aB of the second light guide member 19B, the light from the light output surface 19aB is transmitted to the first light guide member 19A. It can be made to emit without going through.

Further, in the plurality of light guide members 19 to be stacked, the areas of the adjacent light emitting surfaces 19a are substantially equal. This makes it easy to control the drive of each LED 17 in adjusting the brightness per unit area in the light emitted from each light exit surface 19a.

Further, the plurality of light guide members 19 to be stacked have the same dimensions in the scanning direction. In this way, when the plurality of light guide members 19 are stacked, the light guide members 19 can be stacked over the entire area in the scanning direction if the end faces in the scanning direction are aligned. Therefore, each light guide member 19 can be easily positioned and the workability is excellent.

The light guide member 19 has a bottom surface 19c located on the side opposite to the light emitting surface 19a. The light guide member 19 is provided along the bottom surface 19c and includes a reflection sheet (reflecting member) that reflects light. In this way, by reflecting the light in the light guide member 19 by the reflection sheet 20, the light can be efficiently propagated in the light guide member 19 and the light is transmitted to the light emitting surface 19a. Can be launched.

The reflection sheet 20 covers the surface 19d of the light guide member 19 opposite to the light incident surface 19b. In this way, light propagating in the light guide member 19 can be prevented from being emitted from the surface 19d of the light guide member 19 opposite to the light incident surface 19b, thereby further improving the light utilization efficiency. Can be made.

Further, the light source is the LED 17. In this way, high brightness and low power consumption can be achieved.

<Embodiment 2>
A second embodiment of the present invention will be described with reference to FIG. 13 or FIG. In this Embodiment 2, what changed the shape of the light guide member 119 is shown. In addition, the overlapping description about the same structure, an effect | action, and effect as above-mentioned Embodiment 1 is abbreviate | omitted.

Among the light guide members 119 according to the present embodiment, the second light guide member 119B to the fourth light guide member 119D in which the first light guide member 119A to the third light guide member 119C are laminated on the front side are shown in FIG. As shown, a projecting light exiting portion 27 is provided that has light exit surfaces 119aB to 119aD and projects to the front side of the support surface 119e. Each protruding light exit portion 27 is formed such that the light exit surfaces 119aB to 119aD that it has are flush with each other and the light exit surface 119aA of the first light guide member 119A is also flush. ing. Accordingly, the projecting dimension of the projecting light output portion 27B of the second light guide member 119B is about the plate thickness dimension of the first light guide member 119A. Similarly, the projecting dimension of the projecting light output portion 27C of the third light guide member 119C is set to a size that is the sum of the plate thickness dimensions of the first light guide member 119A and the second light guide member 119B. The projecting dimension of the projecting light output portion 27D of the fourth light guide member 119D is set to a size that is the sum of the plate thickness dimensions of the first light guide member 119A to the third light guide member 119C. Thereby, it is possible to eliminate the occurrence of a step between the light emitting surfaces 119aA to 119aD in each of the light guide members 119A to 119D, and the distance between each light emitting surface 119aA to 119aD and the optical member 115, that is, each It is possible to equalize the optical path length until the light emitted from the light emitting surfaces 119aA to 119aD reaches the optical member 115. Therefore, the optical member 115 can be irradiated evenly by the emitted light from each of the light emitting surfaces 119aA to 119aD.

As described above, by making the light emitting surfaces 119aA to 119aD flush with the protruding light emitting portion 27, the following effects can be obtained. For example, as shown in FIG. 14, when the configuration of the backlight device 112 ′ is changed and the optical member 115 ′ is directly stacked on the light guide member 119, they are flush with each other. The optical member 115 'can be stably supported by the light emitting surfaces 119aA to 119aD having a shape.

Of the bottom surfaces 119cB to 119cD of the second light guide member 119B to the fourth light guide member 119D, as shown in FIG. Is formed. The inclined surface 28 has a slope that rises to the front side in the depth direction viewed from the left side in FIG. 13 in the Y-axis direction, that is, from the light incident surface 119b side. Since the reflection sheet 120 is disposed along the inclined surface 28, the light that has reached the protruding light output portions 27B to 27D among the light propagating through the second light guide member 119B to the fourth light guide member 119D is not reflected. By being angled by the portion along the inclined surface 28 in the reflection sheet 120, the reflection sheet 120 is efficiently launched toward the light exit surfaces 119aB to 119aD. Here, in the second light guide member 119B to the fourth light guide member 119D, the light exit surfaces 119aB to 119aD are located farther from the light source unit U (light incident surface 119b) than the first light guide member 119A. Although it is relatively inferior in terms of light utilization efficiency, light can be efficiently launched to the light exit surfaces 119aB to 119aD by the inclined surface 28 described above, and therefore, between the first light guide member 119A and the first light guide member 119A. Differences in light use efficiency are less likely to occur.

Note that the first light guide member 119A has a light exit surface 119aA relatively closer to the light source unit U (light incident surface 119b) than the second light guide member 119B to the fourth light guide member 119D. Even if the inclined surface 28 is not formed, sufficient light use efficiency is ensured. Rather, the first light guide member 119A can stabilize the support posture by setting the bottom surface 119cA in parallel with the support surface 119eB of the second light guide member 119B.

As described above, according to the present embodiment, the second light guide member 119B (third light guide member 119C, fourth light guide member 119D) has the light emission surface 119aB (light emission surface 119aC, light emission surface 119aD). ) And a protruding light emitting portion 27 that protrudes further to the light emission side than the support surface 119eB (support surface 119eC, support surface 119eD). In this way, since the protruding light exiting portion 27 is configured to protrude to the light emitting side from the support surface 119eB, the first light guide member 119A (second light guide member 119B, third light guide member 119C). The step can be reduced or eliminated between the light exit surface 119aA (light exit surface 119aB, light exit surface 119aC) of the light exit surface 119aB of the projecting light exit portion 27 of the second light guide member 119B. Thereby, for example, when other members (such as the optical member 115 ′) are placed on the light exit surface 119 a, the stability is excellent, and from when the light exits each light exit surface 119 a to the other members described above. The difference in optical path length can be reduced or eliminated.

Further, the protruding light exiting portion 27 in the second light guide member 119B is formed such that the light exit surface 119aB it has is flush with the light exit surface 119aA of the first light guide member 119A. In this way, a step can be eliminated between the light exit surface 119a of the first light guide member 119A and the light exit surface 119aB of the protruding light exit portion 27 of the second light guide member 119B. Thereby, for example, when the other member is placed on the light emitting surface 119a, the stability is extremely excellent, and the difference in the optical path length from when the light exits each light emitting surface 119a to the other member described above can be obtained. Can be resolved.

Of the bottom surface 119cB (bottom surface 119cC, bottom surface 119cD) of the second light guide member 119B, a portion overlapping the protruding light emitting portion 27 when viewed in plan is directed in the depth direction viewed from the light incident surface 119b side. An inclined surface 28 having a gradient that rises toward the light emitting side is formed. In this way, the light exit surface 119aB of the second light guide member 119B is relatively far from the light entrance surface 119b in the depth direction as compared to the light exit surface 119aA of the first light guide member 119A. Therefore, although it is relatively inferior in terms of light use efficiency in guiding the light incident on the light incident surface 119b to the light emitting surface 119aB and emitting it, the protrusion having the light emitting surface 119aB among the bottom surface 119cB. Since the inclined surface 28 is formed in a portion overlapping with the light emitting portion 27, the internal light can be efficiently launched toward the light emitting surface 119aB. Thereby, the light use efficiency in the second light guide member 119B can be improved, and a difference in the light use efficiency between the first light guide member 119A can be made difficult to occur.

<Embodiment 3>
A third embodiment of the present invention will be described with reference to FIG. 15 or FIG. In the third embodiment, a pair of light source units 2U is provided and the number and arrangement of light guide members 219 are changed. In addition, the overlapping description about the same structure, an effect | action, and effect as above-mentioned Embodiment 1 is abbreviate | omitted.

Referring to FIGS. 15 and 16, a pair of light source units 2U according to the present embodiment are arranged at both ends of the long side of the chassis 214. Specifically, a predetermined interval is provided between the long side plates 214b on the long side of the chassis 214 and the light guide member 219, and the light source units 2U are arranged in the spaces. The LED 217, the LED substrate 218, the condenser lens 221, the polygon mirror 222, and the synchronization detection unit 223 constituting each light source unit 2U are arranged in a point symmetry with the center position of the light guide member 219 as a symmetric point. On the other hand, the light guide member 219 is configured such that a set of four stacked in the Z-axis direction is arranged back-to-back in the Y-axis direction and sandwiched between the pair of light source units 2U as a whole. It is arranged. Therefore, the light emitting surface of the entire backlight device 212 is divided into 64 regions in a matrix form by the light emitting surfaces 219a of the light guide members 219. Such a configuration is more suitable for increasing the size of the backlight device 212.

<Embodiment 4>
A fourth embodiment of the present invention will be described with reference to FIGS. In this Embodiment 4, what changed further the installation number and arrangement | positioning of the light guide member 319 from above-mentioned Embodiment 3 is shown. In addition, the overlapping description about the same structure, effect | action, and effect as above-mentioned Embodiment 3 is abbreviate | omitted.

As shown in FIGS. 17 to 19, the light guide member 319 according to this embodiment includes eight divided light guide members 319 S divided in the X-axis direction, and four divided light guide members 319 S. Are arranged in such a manner that a pair formed by stacking layers is adjacent to each other in the X-axis direction and reversed in the Y-axis direction. Specifically, there are two types of groups in which the four divided light guide members 319S are stacked, and one group has the same divided light guide members 319S as shown in FIG. In the other set, as shown in FIG. 19, the divided light guide members 319 are arranged near the right side (upper side in FIG. 17). It is a thing. In this embodiment, the divided light guide members 319 S of each set are reversed and arranged in the Y-axis direction so that the sets adjacent to each other in the X-axis direction are the above-described one set and the other set. Specifically, each of the divided light guide members 319SA, 319SC, 319SE, and 319SG forming an odd-numbered set counted from the left end shown in FIG. 17 is arranged close to the left side of the figure as shown in FIG. The split light incident surfaces 319bS are arranged facing the left side of the figure. On the other hand, the light guide members 319SB, 319SD, 319SF, and 319SH that form even-numbered pairs counted from the left end shown in FIG. 17 are arranged close to the right side of the figure as shown in FIG. The split light incident surface 319bS is arranged so as to face the right side of the figure.

The pair of light source units 3U that supply light to the light guide member 319 arranged as described above is controlled by the control unit 25 (see FIG. 6) as follows. In the following description, the lower light source unit 3U shown in FIG. 17 is referred to as a “first light source unit”, and a suffix A is added to the reference numeral, whereas the upper light source unit 3U is referred to as a “second light source unit”. Subscript B shall be attached. That is, among the divided light guide members 319S, the divided light incident surfaces 319bS in the odd-numbered divided light guide members 319SA, 319SC, 319SE, and 319SG are reflected by the reflected light from the polygon mirror 322 forming the first light source unit 3UA. In contrast to the scanning, the divided light incident surfaces 319bS in the even-numbered divided light guide members 319SB, 319SD, 319SF, and 319SH are controlled to be scanned by the reflected light from the polygon mirror 322 forming the second light source unit 3UB. It can be controlled by the unit 25. In this way, there is a non-scanning period in which the divided light incident surface 319bS is not scanned during the scanning period in which the reflected light from each light source unit 3U scans the divided light incident surface 319bS. Since a slight period (non-scanning period) during which the air layer AS between the adjacent divided light guide members 319S can be scanned can be continued, the light emission state of each LED 317 can be controlled more easily.

<Embodiment 5>
A fifth embodiment of the present invention will be described with reference to FIG. 20 or FIG. This Embodiment 5 shows what changed arrangement | positioning of the light source unit 4U, the number of lamination | stacking of the light guide member 419, and the division | segmentation aspect from above-mentioned Embodiment 1. FIG. In addition, the overlapping description about the same structure, an effect | action, and effect as above-mentioned Embodiment 1 is abbreviate | omitted.

The light source unit 4U is disposed at one end of the short side of the chassis 414 as shown in FIG. Specifically, the light source unit 4U is disposed between the light guide member 419 and the side plate 414c on the right short side of the chassis 414 shown in FIG. The LED board 418 and the synchronization detection unit 423 constituting the light source unit 4U are attached to the lower side plate 414b on the lower side shown in FIG. The condenser lens 421 is arranged at a position closer to the LED 417 than the polygon mirror 422. The polygon mirror 422 is disposed at a substantially central position in the entire short side direction of the light guide member 419 (Y-axis direction, scanning direction by reflected light described later). The polygon mirror 422 is rotated in the clockwise direction (arrow line direction) shown in FIG.

Among the light guide members 419, of the both side surfaces along the entire short side direction (Y-axis direction), the surface facing the light source unit 4U is a light incident surface 419b. The light incident surface 419b is linearly scanned from the lower side to the upper side shown in FIG. 20 along the Y-axis direction by the reflected light from the polygon mirror 422 constituting the light source unit 4U. The light guide member 419 is divided along the entire long side direction (X-axis direction), and is divided into six divided guides in the short side direction (Y-axis direction, the scanning direction by reflected light from the polygon mirror 422). It is divided into optical members 419S, and the divided widths are substantially equal. Light from the LED 417 whose light emission state is controlled in a time-sharing manner is incident on each split light incident surface 419bS of each split light guide member 419S via a polygon mirror 422. Furthermore, as shown in FIG. 21, six light guide members 419 are laminated in the Z-axis direction. Note that the laminated structure of the six light guide members 419 is the same as that described in the first embodiment except that the number of the light guide members 419 is increased, and thus a redundant description is omitted. Note that the LED 417 is arranged in parallel in the Z-axis direction in the same number (six) as the number of the light guide members 419 stacked.

<Embodiment 6>
A sixth embodiment of the present invention will be described with reference to FIG. In the sixth embodiment, a pair of light source units 5U described in the fifth embodiment is provided. In addition, the overlapping description about the same structure, an effect | action, and effect as above-mentioned Embodiment 1 is abbreviate | omitted.

Referring to FIG. 22, a pair of light source units 5U according to the present embodiment are arranged at both ends on the short side of the chassis 514. Specifically, a predetermined interval is provided between the short-side side plates 514c and the light guide member 519 in the chassis 514, and the light source units 5U are disposed in the spaces. The LED 517, the LED substrate 518, the condenser lens 521, the polygon mirror 522, and the synchronization detection unit 523 that constitute each light source unit 5U are arranged in a point symmetry with the center position of the light guide member 519 as a symmetric point. On the other hand, the light guide member 519 is configured such that a set of four stacked in the Z-axis direction is arranged back-to-back in the X-axis direction and sandwiched between the pair of light source units 5U as a whole. It is arranged. Therefore, the light emitting surface of the entire backlight device 512 is divided into 48 regions in a matrix by each light emitting surface 519a of each light guide member 519. Such a configuration is suitable for increasing the size of the backlight device 512.

<Embodiment 7>
A seventh embodiment of the present invention will be described with reference to FIG. In the seventh embodiment, a galvanometer mirror 29 is used in place of the polygon mirror 22 described in the first embodiment. In addition, the overlapping description about the same structure, an effect | action, and effect as above-mentioned Embodiment 1 is abbreviate | omitted.

As shown in FIG. 23, the galvanometer mirror 29 has a horizontally long plate shape and a surface facing the light guide member 19 side as a reflection surface 29b, and is rotatable around a rotation shaft 29a. . Specifically, the galvanometer mirror 29 is reciprocally swung around the rotation axis 29a in the direction of the arrow shown in FIG. The angle of the reflection surface 29b is changed in a time division manner, and the traveling direction of the light reflected by the reflection surface 29b is changed in a time division manner. Then, the reflected light from the galvanometer mirror 29 causes the light incident surface 19b (divided light incident surface 19bS) of the light guide member 19 (divided light guide member 19S) to move in the long side direction (X It is possible to scan linearly from the left side to the right side shown in FIG.
In addition, as another example of the rotating reflector that reciprocally swings, a resonant mirror can be cited, which can be used in place of the galvano mirror 29 described above.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) In each of the above-described embodiments, the light guide member is divided into a plurality of parts. However, the present invention includes a structure in which the light guide member is not divided. Specifically, as shown in FIG. 24, each of the light guide members 19A ′ to 19D ′ can be made one, and even in that case, the light-incident surface 19b ′ of FIG. The light emission state of the LED 17 may be controlled in a time-sharing manner for each scanning period of the reflected light from the polygon mirror 22 for each region divided by.

(2) In the first to sixth embodiments described above, the polygon mirror is shown to be square when viewed from the direction along the rotation axis. For example, as shown in FIG. 25, the polygon mirror is along the rotation axis 22a ′. It is also possible to use a polygon mirror 22 ′ that is a regular hexagon when viewed from the direction.

(3) In addition to the above (2), the shape of the polygon mirror viewed from the direction along the rotation axis may be other regular polygons such as a regular triangle, a regular pentagon, a regular heptagon, and a regular octagon. It is.

(4) In addition to the above (3), the shape of the polygon mirror viewed from the direction along the rotation axis may be a non-regular polygon such as an isosceles triangle or a trapezoid.

(5) In each embodiment described above, a polygon mirror, a galvano mirror, and a resonant mirror are exemplified as the rotating reflector. However, other rotating reflectors using MEMS (Micro Electro Mechanical System) technology are used. Is also possible.

(6) In the above-described embodiments, the number of laminated light guide members and the number of installed LEDs are shown to be the same. However, it is not always necessary to match both, for example, compared to the number of laminated light guide members. Those having a small number of installed LEDs and those having a large number are also included in the present invention.

(7) In each of the above-described embodiments, one LED is provided for each stage (first LED to fourth LED). However, the present invention is also provided with a plurality of LEDs for each stage. include. In this way, the luminance can be improved. It should be noted that light from a plurality of LEDs in each stage can be irradiated while efficiently condensing the polygon mirror by changing the optical design of the condenser lens.

(8) In the above-described embodiments, four or six light guide members are stacked. However, the number of light guide members stacked is appropriately changed to other than four or six. be able to. When the number of light guide members stacked is changed, it is preferable that the number of LEDs arranged in the stacking direction is also changed to be the same as the number of light guide members stacked.

(9) In each of the above-described embodiments, the light incident surfaces of the stacked light guide members are arranged so that they are flush with each other. However, the light incident surfaces of the stacked light guide members are surfaces. What was made into the arrangement | positioning which does not form one shape is also contained in this invention. In that case, it is preferable to make the optical path lengths until the light emitted from the LEDs of each stage reaches the light incident surface by changing the shape of the reflecting surface of the polygon mirror or the arrangement of the LEDs.

(10) In each of the above-described embodiments, the control unit performs PWM control of the light emission state of the LED, but it is of course possible to control the LED light emission state by other methods. For example, the light emission state of the LED can be controlled in a time-sharing manner by changing the drive voltage for driving the LED in a time-sharing manner.

(11) In each of the above-described embodiments, the case where the light emission state of the LED is synchronized with the rotation state (rotation state) of the polygon mirror (galvano mirror) by the synchronization detection unit has been described. It can be omitted. In that case, for example, a sensor is provided in an electromagnetic motor for rotationally driving the polygon mirror so that the rotation state is directly detected, and the light emission state of the LED is controlled by the control unit based on the detection signal. .

(12) In each of the above-described embodiments, the division width in the light guide member, that is, the case where the dimensions in the scanning direction in each division light guide member are substantially equalized, but the division width in the light guide member is set to be different. It is also possible.

(13) In each of the above-described embodiments, each light guide member is divided into six or eight. However, the number of divisions of each light guide member is appropriately changed to other than six and eight. be able to.

(14) In the first embodiment described above, among the two side plates on the short side of the chassis, the left side plate shown in FIG. 3 is attached with the LED substrate and the synchronization detection unit. Of course, it does not matter if the LED substrate and the synchronization detection unit are attached to the side plate on the right side.

(15) In the fifth embodiment described above, among the both side plates on the long side of the chassis, the lower side plate shown in FIG. 20 is attached with the LED substrate and the synchronization detection unit. Of course, the LED board and the synchronization detection unit may be attached to the upper side plate shown in FIG.

(16) In the above-described embodiments, the LED board is attached to the side plate of the chassis. For example, a heat sink having an L-shaped cross section is prepared, the LED board is attached to the heat sink, and the heat sink is attached to the chassis. It may be attached to the bottom plate.

(17) In each of the above-described embodiments, one or two light source units are arranged in the chassis, but three or four light source units are arranged in the chassis. included.

(18) In each of the above-described embodiments, an arrangement in which the alignment direction of the LED, the condenser lens, and the polygon mirror (galvano mirror) is orthogonal to the alignment direction of the polygon mirror (galvano mirror) and the light guide member is used. Although illustrated, it is also possible to set the above-described two alignment directions to make an angle of 90 degrees or more (obtuse angle) or to make an angle of 90 degrees or less (acute angle). Even in that case, it is preferable that the traveling direction of the light condensed by the condenser lens is set to coincide with the arrangement direction of the LED and the polygon mirror (galvano mirror).

(19) In each of the above-described embodiments, the polygon mirror (galvano mirror) is arranged at the substantially central position in the scanning direction on the light incident surface. However, the polygon mirror (galvano mirror) is displaced from the central position. What was made into the arrangement | positioning was also included in this invention.

(20) In each of the above-described embodiments, the LED is arranged at the position that is the end in the scanning direction on the light incident surface. Those arranged close to each other are also included in the present invention.

(21) In each of the above-described embodiments, the synchronization detection unit is attached to the same side plate as the LED substrate and is disposed at a position between the LED and the light guide member. Can be attached to a side plate (for example, the opposite side plate) different from the LED substrate. Furthermore, it is also possible to place the synchronization detection unit on the same side plate as the LED substrate, and arrange the LED between the light guide member and the LED.

(22) In each of the above embodiments, the air layer is used as the low refractive index layer interposed between the adjacent divided light guide members. However, a low refractive index layer made of a low refractive index material may be used. Is possible.

(23) In each of the above-described embodiments, the air layer is interposed between the adjacent divided light guide members. However, instead of the air layer, a reflective layer made of a reflective sheet having excellent light reflectivity is used. It is also possible.

(24) In each of the above-described embodiments, the case where the condensing lens is used as the condensing member is shown, but a condensing member other than the lens may be used.

(25) In each of the above-described embodiments, the LED is used as the light source. However, other types of light sources (cold cathode tube, hot cathode tube, laser light source, etc.) can of course be used.

(26) In each of the above-described embodiments, a specific example of the display period of one display image on the liquid crystal panel is 1/60 seconds or 1/120 seconds. It is also possible to change to 240 seconds or the like, and the scanning period for the light incident surface by the reflected light of the rotating reflector may be changed accordingly. In addition, the specific numerical value of the above-described display period can be appropriately changed in addition to the above.

(27) In Embodiment 3 and Embodiment 6 described above, the LED substrates and the synchronization detection units in the pair of light source units are attached to different side plates, but these are attached to the same side plate. Are also included in the present invention. In that case, the polygon mirror that forms one light source unit and the polygon mirror that forms the other light source unit may be set so that the rotation directions are opposite.

(28) In each of the above embodiments, the bottom surfaces of the first light guide member to the third light guide member and the support surfaces of the second light guide member to the fourth light guide member that receive the bottom surface are parallel to each other. Although shown, the present invention includes a configuration in which the bottom surface and the support surface are not parallel to each other.

(29) In each of the above-described embodiments, the light output surfaces of the light guide members stacked on each other are shown to have the same area. However, the areas of the light output surfaces of the light guide members stacked on each other are Partially or entirely different settings are possible.

(30) In the above-described embodiments, the width dimensions of the light guide members stacked on each other are the same, but the width dimensions of the light guide members stacked on each other are set to be partially or completely different. It is also possible.

(31) In each of the above-described embodiments, the LEDs arranged along the light guide member stacking direction are linearly arranged. However, the LEDs aligned along the light guide member stacking direction are arranged in the X axis. Those that are displaced in the direction or the Y-axis direction are also included in the present invention.

(32) In each of the above-described embodiments, the case where the reflection sheet arranged along the bottom surface of the light guide member is a single sheet covering the surface opposite to the light incident surface is shown. Also, the present invention includes a configuration in which two reflection sheets are configured and divided into one that covers the bottom surface of the light guide member and one that covers the surface opposite to the light incident surface of the light guide member.

(33) In each of the above-described embodiments, the reflection sheet covers the entire support surface of the light guide member laminated on the back side, but the support surface of the light guide member on which the reflection sheet is laminated on the back side is partially What was made into the form covered automatically is also contained in this invention.

(34) In each of the above-described embodiments, the reflection sheet is configured to cover the surface opposite to the light incident surface in addition to the bottom surface of the light guide member. It is also possible to adopt a form in which only the bottom surface of the light incident surface is covered and the surface opposite to the light incident surface is not covered.

(35) In each of the above-described embodiments, the liquid crystal panel is illustrated in a vertically placed state in which the short side direction coincides with the vertical direction, but the liquid crystal panel matches the long side direction with the vertical direction. What is set in a vertical state is also included in the present invention.

(36) In the above-described embodiment, the TFT is used as the switching element of the liquid crystal display device. However, the present invention can also be applied to a liquid crystal display device using a switching element other than the TFT (for example, a thin film diode (TFD)), and color display. In addition to the liquid crystal display device, the present invention can be applied to a liquid crystal display device that displays black and white.

(37) In each of the above-described embodiments, the liquid crystal display device using the liquid crystal panel as the display panel has been exemplified. However, the present invention can be applied to display devices using other types of display panels.

(38) In each of the above-described embodiments, the television receiver provided with the tuner is exemplified, but the present invention is also applicable to a display device not provided with the tuner.

DESCRIPTION OF SYMBOLS 10 ... Liquid crystal display device (display device), 11 ... Liquid crystal panel (display panel), 12, 212, 512 ... Backlight device (illumination device), 17, 117, 217, 317, 418 ... LED (light source), 19, 119, 219, 319, 419, 519 ... light guide member, 19A, 119A ... first light guide member, 19B, 119B ... second light guide member (first light guide member), 19C, 119C ... third light guide member (1st light guide member, 2nd light guide member), 19D, 119D ... 4th light guide member (2nd light guide member), 19S, 319S, 419S ... division | segmentation

light guide member

19a, 119a, 219a, 519a ... light Output surface, 19b, 119b, 419b ... light incident surface, 19bS, 319bS, 419bS ... split light incident surface (region), 19c, 119c ... bottom surface, 19d ... surface, 19e, 119e ... support surface, 20 120 ... reflective sheet (reflective member) 21,221,421,521 ... condensing lens (condensing member) 22,222,322,422,522 ... polygon mirror (rotating reflector), 22a ... rotating shaft ( Axis), 22b, 29b ... reflecting surface (surface), 25 ... control unit, 27 ... projecting light exiting portion, 28 ... tilted surface, 29 ... galvanomirror (rotating reflector), AS ... air layer (low refractive index layer) , TV ... TV receiver

Claims

Stacked so as to have a light incident surface on which light is incident and a light emitting surface for emitting incident light, and the light emitting surfaces are adjacent to each other in the depth direction viewed from the light incident surface side. A plurality of light guide members arranged as
A plurality of light sources arranged side by side along the stacking direction of the light guide members;
A rotating reflector that reflects light from the light source while being rotated about an axis along the stacking direction of the light guide member, and scans the light incident surface with the reflected light; and
When the light incident surface is divided into a plurality of regions in the scanning direction by the reflected light from the rotating reflector, the light emission state of the light source is time-divided in association with the reflected light scanning period for each region. An illuminating device provided with the control part to control.
The illuminating device according to claim 1, wherein the number of the light guide members to be laminated matches the number of the light sources arranged side by side in the lamination direction of the light guide members.
The lighting device according to claim 1 or 2, wherein an arrangement direction of the light source and the rotating reflector and an arrangement direction of the rotating reflector and the light guide member are substantially orthogonal to each other.
The lighting device according to any one of claims 1 to 3, wherein the rotating reflector is disposed at a substantially central position of the light incident surface in the scanning direction.
The illuminating device according to any one of claims 1 to 4, wherein the light source is disposed on an end side of the light incident surface in the scanning direction.
The lighting device according to any one of claims 1 to 5, wherein the plurality of regions on the light incident surface are partitioned so that dimensions in the scanning direction are substantially the same.
The illumination device according to any one of claims 1 to 6, wherein the rotating reflector is configured by a polygon mirror that rotates in one direction.
The illumination device according to claim 7, wherein the polygonal mirror has a regular polygonal shape when viewed from the direction along the rotation axis.
The lighting device according to claim 8, wherein the polygonal mirror has a square shape when viewed from a direction along a rotation axis thereof.
10. The light emitting device according to claim 1, further comprising a condensing member that is interposed between the light source and the rotating reflector and collects light from the light source and emits the light toward the rotating reflector. The lighting device according to item 1.
The said condensing member condenses the light from the said light source so that the advancing direction of the light radiate | emitted toward the said rotation reflector may be parallel to the said light-incidence surface. apparatus.
The lighting device according to any one of claims 1 to 11, wherein the control unit is configured to periodically blink the light source to change a time ratio between a lighting period and a non-lighting period.
The lighting device according to any one of claims 1 to 12, wherein the light guide member includes a plurality of divided light guide members divided for each of the plurality of regions on the light incident surface.
The lighting device according to claim 13, wherein a low refractive index layer having a refractive index relatively lower than that of the divided light guide member is interposed between the adjacent divided light guide members.
The lighting device according to claim 1, wherein the plurality of light guide members to be stacked are arranged such that the light incident surfaces are flush with each other.
The rotating reflector has a reflecting surface that reflects light from the light source and can be parallel to the light incident surface, whereas the plurality of light sources arranged along the stacking direction are parallel to the reflecting surface. The lighting device according to claim 15, wherein the lighting device is arranged in a straight line so as to.
The lighting device according to any one of claims 1 to 16, wherein the light guide member has a bottom surface that is located on a side opposite to the light emitting surface and is parallel to the light emitting surface.
The plurality of light guide members to be stacked are relatively arranged on a side opposite to the light output side with respect to the first light guide member, relative to the first light guide member disposed on the light output side And at least a second light guide member disposed,
The second light guide member has a support surface that supports the bottom surface of the first light guide member, and the light is adjacent to the support surface in the depth direction viewed from the light incident surface side. The lighting device according to any one of claims 1 to 17, further comprising an emission surface.
The lighting device according to claim 18, wherein the second light guide member is provided with a protruding light output portion that has the light output surface and protrudes further toward the light output side than the support surface.
The projecting light exit portion of the second light guide member is formed so that the light exit surface thereof is flush with the light exit surface of the first light guide member. Lighting equipment.
Of the bottom surface of the second light guide member, a portion that overlaps with the protruding light exiting portion when viewed in plan is a gradient that rises toward the light exiting side in the depth direction viewed from the light incident surface side. 21. The lighting device according to claim 19 or 20, wherein an inclined surface having the shape is formed.
The lighting device according to any one of claims 1 to 21, wherein the plurality of light guide members to be stacked have substantially the same area between adjacent light emitting surfaces.
The lighting device according to any one of claims 1 to 22, wherein the plurality of light guide members to be stacked have the same dimension in the scanning direction.
The light guide member has a bottom surface located on the opposite side of the light emitting surface,
The lighting device according to any one of claims 1 to 23, further comprising a reflecting member that is disposed along the bottom surface and reflects light.
The lighting device according to claim 24, wherein the reflecting member covers a surface of the light guide member opposite to the light incident surface.
The lighting device according to any one of claims 1 to 25, wherein the light source is an LED.
A display device comprising: the lighting device according to any one of claims 1 to 26; and a display panel that performs display using light from the lighting device.
28. The display device according to claim 27, wherein the display panel is a liquid crystal panel in which liquid crystal is sealed between a pair of substrates.
A television receiver comprising the display device according to claim 27 or claim 28.