JP2008299116A - Equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device which can express light beams from different light sources on the same plane, and to display design requiring fine expression. <P>SOLUTION: A portable phone 10 includes: a light source 4 provided in a housing 5; and a light guide plate 1 provided in the housing 5, where a plurality of recessed parts 2 each having a reflection surface 2a to reflect the light beam emitted from the light source 4 toward the surface side as an image display screen of the housing 5 are formed. Regarding the housing 5, a part where the light guide plate 1 is provided can be translucent. Further, an opaque sheet is preferably provided under the light guide plate 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a device such as a mobile phone.

  In recent years, LEDs (light-emitting diodes) have been increasingly used for various purposes as high-efficiency, long-life light sources.

  For example, there are many cases where an LED is provided in a device that has been distributed in recent years. The LED provided in the device is lit according to the function of each device, and is used to make the user recognize the state of the device. Specific examples of the device include various information devices such as a mobile phone, a PDA, and a game machine, and electric devices such as a television, an audio, a refrigerator, and a vending machine.

  In these devices, a display method may be employed in which a self-luminous display device is arranged inside the housing and characters, patterns, and the like emerge through the translucent housing when turned on. Examples of the display device include a liquid crystal display device, an organic EL, and an LED display. If the pattern is very simple, the LED may be arranged at a specific position.

  In addition, as a display device having transparency and excellent design properties, there is a display device in which a surface of a light guide plate is roughened by laser processing or etching to form a display portion that forms a figure, a logo, or the like. In such a display device, a relatively complicated design such as a logo or a pattern is processed by laser processing or etching on the light guide plate, and a light source such as an LED is incident from the end face of the light guide plate to display these designs in a light emitting manner. Can do. This display device can emit a specific design at a lower cost than a liquid crystal display device, an organic EL, or the like.

  This display device emits light from a light source provided on an end face of a light guide plate to raise a display unit, and is used for a display or the like.

A display device having a display unit in which LED elements are provided in a predetermined arrangement between two transparent glass plates is also used (see, for example, Patent Document 1).
European Patent No. 099199

  In the display device having the roughened display portion, light is scattered by the display portion, so that the luminance per unit area of the display portion is lowered and the visibility becomes insufficient. In order to improve visibility, it is necessary to increase the area of the display portion.

  However, if the area of the display portion which is an opaque portion is large, the background cannot be seen through, and the transparency which is a characteristic of this display device is lost, and its value is diminished.

  In the display device in which the LED element is provided between the transparent glass plates, the transmitted light is blocked only by the LED element, so that the transparency is good. However, the electrode wiring pattern is complicated, so that it is difficult to manufacture and is very expensive. .

  In addition, unlike a display device in which the light source and the light guide plate are separate bodies, it is necessary to replace the entire light source (LED element) including the light source in order to change the design of the display unit.

In addition, when installing a display device having such a roughened display unit inside the housing,
(1) Light source intensity must be increased, resulting in increased cost (2) Transparency of the casing must be increased, and the light guide plate and other internal structures can be seen through easily (3) The scattered light becomes stray light, which causes various problems such as the light guide plate and other internal structures appearing brightly.

  In addition, in the above-described device, when it is only necessary to display a design such as a specific logo or pattern, there is a problem that costs are increased when a liquid crystal display device, an organic EL, an LED display, or the like is used.

  The present invention has been made in view of the above circumstances, and provides a device that can easily display a display unit provided in a housing, can be easily manufactured at low cost, and can express a complicated design. With the goal.

In order to achieve the above object, a device according to a feature of the present invention includes a light source provided inside a housing, and a light source provided inside the housing, which transmits light from the light source to the surface side of the housing, which is an image display surface. And a light guide plate having a plurality of recesses having a reflecting surface to be reflected. Here, it is preferable that a portion where an image is displayed is translucent in the housing. In this case, it is preferable that a black sheet is provided below the light guide plate.

  Further, a plurality of light sources may be provided. In this case, it is preferable that the light guide plate has a plurality of recesses having a reflection surface that reflects light from any one of the plurality of light sources to the housing side. Furthermore, it is preferable to provide a plurality of light guide plates corresponding to each of the plurality of light sources. It is preferable that a black sheet is provided below the plurality of light guide plates.

  Here, it is preferable that any one or more combinations of characters, symbols, figures, and patterns are displayed on the display surface. Moreover, it is preferable that a recessed part consists of a dot-shaped notch formed in the light-guide plate. Furthermore, it is preferable that the reflection surface of the recess has an angle of 45 degrees or more and 60 degrees or less with respect to the surface where the light source is formed. The concave portion has a substantially rectangular shape in plan view, and the aspect ratio is preferably in the range of 10: 1 to 1: 1.

  The light source is preferably formed so as to extend along the extending direction of the light guide plate. It is preferable that the light source has a plurality of light emitting diodes arranged in a predetermined direction.

  Here, it is preferable that the surface which opposes the surface into which light injects among the surfaces of a light-guide plate is processed to suppress reflection of light.

  In the device of the present invention, the display portion provided in the housing is easy to visually recognize, can be easily manufactured at low cost, and can express a complicated design.

  The best mode for carrying out the display device of the present invention will be described below with reference to the drawings. In the best mode of the present invention, a mobile phone will be described as an example of a device.

  FIG. 1 shows a mobile phone 10 according to the preferred embodiment of the present invention. FIG. 2 is an enlarged view of a partial cross section of the upper portion of the mobile phone 10.

  As shown in FIG. 1, the mobile phone 10 is a foldable mobile phone, and in the best mode of the present invention, the light guide plate 1 is provided inside the upper portion 10 a of the mobile phone 10.

  As shown in FIGS. 1 and 2, a mobile phone 10 according to the best mode of the present invention is provided on a housing 5, a transparent light guide plate 1 having a parallel plane, and an end face 1 a of the light guide plate 1. 1 includes a light source 4 that emits light toward 1 and a sheet 6. The surface of the housing 5 of the mobile phone 10 shown in FIGS. 1 and 2 includes an opaque portion 5a and a translucent portion 5b. The light guide plate 1 is provided inside the translucent portion 5b in parallel with the translucent portion 5b, and the light reflected from the light guide plate 1 is displayed on the translucent portion 5b.

  The translucent portion 5b transmits light from the light guide plate 1 described later. The translucent portion 5b may be colored or may not be colored. In this embodiment, the case where it is colored black will be described.

  First, the light source 4 will be described. The light source 4 is provided inside the housing 5, and emits light that causes the light guide plate 1 to display an image through reflection by the dot-like reflection part (concave part) 2. As the light source 4, an LED, an LD (laser diode), or the like can be used. The light source 4 is formed so as to extend along the extending direction of the light guide plate 1. As shown in FIG. 1, the light source 4 is preferably provided under the opaque portion 5 a of the housing 5 in order to prevent deterioration of the appearance of the mobile phone 10.

  As the light source 4, for example, a plurality of LEDs arranged in a direction along the end face 1a can be used. Moreover, the color of the light emitted from the light source 4 can be any color such as white, red, green, and blue, and can be selected as appropriate according to the pattern formed by the dot-like reflection unit 2.

  Next, the light guide plate 1 will be described. The light guide plate 1 is provided inside the housing 5, and a plurality of dot reflection portions (concave portions) 2 are formed. The dot reflection unit 2 has a reflection surface that reflects light from the light source 4 to the surface side of the housing 5 that is an image display surface. The light guide plate 1 may be a transparent material, and a plate made of a synthetic resin such as an acrylic resin, a polycarbonate resin, a silicone resin, a cyclopolyolefin resin, or a glass plate is used. Among them, transparency and easy processing are used. An acrylic board is preferable from the standpoints of height.

  The thickness of the light guide plate 1 can be set to 0.5 mm to 10 mm, for example.

  Of the surfaces of the light guide plate 1, it is preferable that the surface 1 d facing the surface 1 a on which light is incident is subjected to a process for suppressing light reflection. Specifically, the treatment for suppressing the reflection of light includes, for example, applying a black coating on the surface 1d of the light guide plate 1 or attaching an antireflection sheet. By this process, in order to prevent the light reflected by the surface 1d from becoming stray light, the visibility of the reflected light emitted from the light guide plate 1 is enhanced when the mobile phone 10 is viewed from the outside when the light source 4 is turned on. Can do.

  As shown in FIGS. 2 and 3, a plurality of dot-like reflecting portions 2 are formed on the back surface 1 c of the light guide plate 1. As shown in FIG. 3, the dot-like reflecting portion 2 is a notch formed in the back surface 1 c.

  In the illustrated example, a plurality of dot-like reflecting portions 2 are arranged on the back surface 1c of the light guide plate 1 so as to form a predetermined pattern. The back surface 1c is provided with a combination of one or more of characters, symbols, figures, and patterns. When incident light from the light source 4 is reflected by the respective dot-like reflecting portions 2 and reflected on the surface of the housing 5 which is a display surface, the translucent portion 5b of the housing 5 is seen from the outside of the mobile phone 10. The dot-like reflecting portion 2 is displayed as a dot-like bright spot, and any one or more combinations of characters, symbols, figures, and patterns are displayed.

  “The dot-like reflecting portion 2 forms a predetermined pattern” means that the dot-like reflecting portion 2 has a densely arranged portion and a sparsely arranged portion. It means that it is arranged uniformly.

  In the mobile phone 10, a configuration (for example, a light diffusing plate) that impairs the transparency of the display device 10 is not provided on the surface 1 b side of the light guide plate 1, and the dot-like reflecting portion 2 has a dot-like bright spot. As visible.

  On the other hand, a black sheet 6 is provided on the back surface 1 c side of the light guide plate 1. The seat 6 has a role of concealing each mechanism of the mobile phone 10 provided under the seat 6 when the mobile phone 10 is viewed from the outside. In addition, by making the sheet 6 black, it is possible to prevent the sheet itself from brightly rising due to stray light. Thereby, the visibility of the reflected light emitted from the light guide plate 1 can be enhanced when the cellular phone 10 is viewed from the outside when the light source 4 is turned on.

  Further, a black sheet may be disposed as the sheet 6 regardless of the color of the translucent portion 5 b of the housing 5. In the case of a black sheet, the visibility of reflected light emitted from the light guide plate can be enhanced regardless of the color of the translucent portion 5b.

  As shown in FIGS. 1 and 2, in the mobile phone 10 according to this embodiment, designs such as characters, symbols, figures, patterns, and the like can be displayed on the housing 5 of the mobile phone 10.

  Conventionally, when a design is displayed on a mobile phone, one light source (LED) is required for one bright spot. In the mobile phone 10 according to the present embodiment, a single light source is incident on a plurality of bright spots. Therefore, a complicated design can be expressed at low cost.

  Further, when a plurality of LEDs are used as the light source 4 arranged in the direction along the end surface 1a, various colors are displayed on the translucent portion 5b by changing the color of each LED and switching the LED to be lit. be able to.

  Here, in the present embodiment, the cellular phone 10 has been described as an example, but various devices such as information devices such as PDAs, game machines, and notebook computers, and electrical devices such as televisions, audios, refrigerators, and vending machines. Of course, it can be diverted.

  Next, the dot-shaped reflection part 2 is demonstrated. In the example shown in FIG. 1 and FIG. 2, the mobile phone 10 according to the best embodiment of the present invention is a reflective surface that reflects light from the light source 4 to the surface side of the casing 5 of the image in the light guide plate 1. A plurality of dot-like reflecting portions 2 having In the present embodiment, the dot-like reflecting portion 2 has a substantially rectangular shape in plan view (see FIG. 4), and has a cross section that is a triangle with the reflecting surface 2a as a hypotenuse (see FIG. 3).

  The dot-like reflecting part 2 may be any structure as long as it is formed in the light guide plate 1 and reflects the light from the light source 4 to the surface side of the housing 5, and its configuration is not limited to the illustrated example. For example, it may be a notch having a cross-sectional shape such as a quadrilateral or more polygon (for example, trapezoid) or a sector. Moreover, the through-hole formed in the light-guide plate 1 may be sufficient, and the space part formed in the light-guide plate 1 may be sufficient.

  The aspect ratio (aspect ratio) (average value) of the dot-like reflecting portions 2 when viewed in plan is preferably in the range of 10: 1 to 1: 1, and preferably in the range of 5: 1 to 1: 1. Is more preferable.

  As shown in FIG. 4, the aspect ratio means β1: β2. β1 is the planar view length (length in the light incident direction) of the hypotenuse 2b of the dot-like reflector 2 shown in FIGS. 3 and 4, and β2 is the upper side 2c orthogonal to the light incident direction and This is the length of the lower side 2d.

  If the length β1 with respect to the length β2 is too large, the shape of the light from the dot-like reflecting portion 2 becomes close to a linear shape, which is not preferable because the transparency characteristic of the display device 10 is impaired. If the length β1 with respect to the length β2 is too small, the luminance of the dot-like reflecting portion 2 becomes too low. Note that β2: β1 can also be considered as an aspect ratio.

  The aspect ratio refers to the ratio of the long side to the short side (long side: short side) of the rectangle having the smallest area that is inscribed by the dot-like reflecting portion 2 in plan view.

  In addition, the planar view shape of the dot-shaped reflection part 2 is not limited to the illustrated example, and may be a polygon such as a triangle or a pentagon, a circle, or an ellipse.

  If the inclination angle (angle α shown in FIG. 3) of the reflection surface 2a with respect to the back surface 1c of the light guide plate 1 is too small, the inclination angle of the emitted light also increases, and the dot-like reflection portion 2 when the display device 10 is viewed from the front. Visibility is reduced. If the inclination angle α is too large, the incident angle of light exceeds the critical angle and the proportion of light transmitted through the reflecting surface 2a increases, so that the light reflection efficiency decreases and the light use efficiency decreases.

  For this reason, the inclination angle α of the reflecting surface 2a is preferably 45 degrees or more and 60 degrees or less, and more preferably 50 degrees or more and 55 degrees or less. By setting the inclination angle α in the above range, the light reflection efficiency can be increased, and the reflected light can be emitted at an angle close to perpendicular to the surface 1b, so that the visibility of the dot-like reflecting portion 2 can be enhanced.

  In the illustrated example, the reflecting surface 2a is flat, but at least a part of the reflecting surface may be curved. If the reflection surface is a curved surface, the emission angle of the reflected light may extend over a wide range. In this case, the dot-like reflection unit 2 can be viewed from a wide range.

  The surface roughness (maximum height Ry) of the reflecting surface 2a (JIS B 0601-1994) is preferably a smooth flat surface in order to increase the light reflection efficiency on the reflecting surface 2a.

  In the dot-like reflecting portion 2, the brightness of the reflected light from the dot-like reflecting portion 2 is set according to the planar view area (β1 × β2) of the reflecting surface 2a. The planar view area of the reflecting surface 2a is adjusted by changing the height γ of the dot-like reflecting portion 2, the length β2 of the upper side 2c (lower side 2d), and the like, whereby the luminance of the reflected light of the dot-like reflecting portion 2 is adjusted. Adjusted.

  As shown in FIG. 3, in the mobile phone 10, light from the light source 4 can be incident on the light guide plate 1 from the end surface 1 a, reflected on the reflecting surface 2 a of the dot-like reflecting portion 2, and emitted from the surface 1 b side. . When viewed from the front surface 1b side, the dot-like reflecting portion 2 is observed as a dot-like bright spot.

  The light from the light source 4 is reflected at a high reflectivity on the reflecting surface 2a and travels in a substantially constant direction (in the illustrated example, a direction perpendicular to the surface 1b), so that the luminance per unit area of the reflected light is sufficiently large. . For this reason, even when observing at a distance, excellent visibility is obtained.

  As described above, since a complicated design can be easily realized, it is possible to express and change a complicated design at low cost by introducing it into the mobile phone 10 of the present embodiment. .

  In addition, the design can be displayed with sufficient brightness because the reflection efficiency of each dot-like reflecting portion is good without increasing the light intensity of the light source.

  By providing a black sheet at the lower part of the light guide plate 1 and further applying a treatment for suppressing light reflection on the surface opposite to the surface on which light is incident on the light guide plate 1, stray light is suppressed and the design visibility is reduced. Can be prevented.

  Further, since the structure is simple, manufacturing is easy and advantageous in terms of cost. Furthermore, since the light guide plate 1 and the light source 4 are separate bodies, there is an advantage that it is easy to replace the light guide plate 1 with a light guide plate having a different pattern.

  Next, an example of a method for manufacturing the light guide plate 1 of the mobile phone 10 will be described with reference to FIGS.

  In the formation of the dot-like reflecting portion 2, as shown in FIG. 5, a processing tool 13 having a blade portion 12 protruding from the lower surface of the base portion 11 is used. The blade portion 12 has a shape corresponding to the dot-like reflecting portion 2, and the vertex angle (vertex angle δ shown in FIG. 5) of the blade portion 12 is preferably 10 to 40 degrees.

  In order to form the reflecting surface 2a smoothly, it is preferable that the inclined surface 12a of the blade portion 12 which is the surface forming the reflecting surface 2a is also formed smoothly.

  As shown in FIGS. 6 and 7, the processing tool 13 is lowered along the forming direction of the blade portion 12, the blade portion 12 is pushed into the back surface 1 c of the light guide plate 1, and the processing tool 13 is raised to raise the blade portion 12. Pull out.

  At this time, if one or both of the blade portion 12 and the light guide plate 1 are heated to a temperature equal to or higher than the softening point of the material of the light guide plate 1, the dot-like reflection portion 2 can be easily formed.

  As a result, a dot-like reflecting portion 2 having a shape along the blade portion 12 is formed on the back surface 1 c of the light guide plate 1. Furthermore, the light guide plate 1 shown in FIGS. 1 and 2 is obtained by moving the processing tool 13 horizontally and repeating the same operation to form another dot-like reflecting portion 2.

  According to the manufacturing method using the processing tool 13, the dot-shaped reflection part 2 of an exact shape can be formed. Moreover, the reflective surface 2a can be formed smoothly.

  Other manufacturing methods include cutting, press molding, injection molding, and the like. Among these, cutting, press molding, and injection molding have the advantage that the reflecting surface 2a can be formed relatively smoothly. Moreover, press molding and injection molding can be accurately formed even with a small dot-like reflecting portion 2. Further, since the cutting process does not require a mold, the manufacturing cost can be reduced, which is particularly advantageous in the case of processing a light guide plate having a large area or small-scale production.

(Modification)
With reference to FIG. 8 to FIG. 10, a mobile phone 10 according to a modification of the preferred embodiment of the present invention will be described.

  The mobile phone 10 according to the modification of the present invention is different from the best embodiment of the present invention described with reference to FIGS. 1 and 2 in that a plurality of light guide plates and light sources are provided.

  As shown in FIG. 1, the light source 4 a and the light source 4 b are preferably provided under the opaque portion 5 a of the housing 5 in order to prevent deterioration of the appearance of the mobile phone 10, as in the best embodiment.

  The light source 4 a makes light incident on the light guide plate 1. The incident light is reflected by the reflecting surface 2 a of the dot-like reflecting portion 2 provided on the light guide plate 1, so that the pattern of the dot-like reflecting portion 2 provided on the light guide plate 1 is reflected on the translucent portion 5 b of the housing 5. The corresponding design can be displayed. On the other hand, the light source 4 b makes light incident on the light guide plate 7. The incident light is reflected by the reflecting surface 2 a of the dot-like reflecting portion 2 provided on the light guide plate 7, so that the pattern of the dot-like reflecting portion 2 provided on the light guide plate 7 is reflected on the translucent portion 5 b of the housing 5. The corresponding design can be displayed.

  As shown in FIG. 10, the light guide plate 1 is provided with the dot-like reflecting portion 2 in the shape of “◯”, while the light guide plate 7 is provided with the dot-like reflecting portion 2 in the shape of “Δ”. In this way, by forming a pattern with the dot-like reflecting portion 2 in each light guide plate, a plurality of designs can be displayed in an overlapping manner on the translucent portion 5b of the mobile phone 10 as shown in FIG. . By making the color of the light source different or changing the state of each light source such as a dot, a complicated display can be performed on the opaque portion of the housing 5.

  Here, the sheet 6 is provided under the light guide plate 1 and the light guide plate 7 as in the best embodiment.

  The thickness of the light guide plate 1 and the light guide plate 7 can be set to, for example, 0.5 mm to 10 mm. However, by using a light guide plate as thin as possible, a plurality of thicknesses can be obtained without affecting the size of the mobile phone 10. More complicated designs can be displayed by overlapping the light guide plates.

  In the example illustrated in FIGS. 8 to 10, the case where two light guide plates are used has been described. However, the number is not limited to two and may be three or more.

(Other embodiments)
As described above, the present invention has been described according to the best mode and modifications. However, it should not be understood that the description and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples, and operational techniques will be apparent to those skilled in the art.

  It goes without saying that the present invention includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

FIG. 1 is a plan view schematically showing a mobile phone according to the best mode of the present invention. FIG. 2 is a cross-sectional view of a part of the mobile phone shown in FIG. FIG. 3 is an enlarged cross-sectional view of a main part of the light guide plate of the mobile phone shown in FIG. FIG. 4 is a plan view of the dot-like reflecting portion of the mobile phone shown in FIG. FIG. 5 is a process diagram showing a method of manufacturing the mobile phone shown in FIG. FIG. 6 is a process diagram following FIG. FIG. 7 is a process diagram following FIG. FIG. 8 is a plan view of a mobile phone according to a modification of the preferred embodiment of the present invention. FIG. 9 is a partial cross-sectional view of the mobile phone shown in FIG. FIG. 10 is a perspective view schematically showing a light guide plate of a mobile phone according to a modification of the best embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 7 Light-guide plate 2 Dot-shaped reflection part 2a Reflecting surface 3 Display part 4, 4a, 4b Light source 10 Mobile telephone 11 Base part 12 Blade part 13 Processing tool

Claims (13)

A light source provided inside the housing;
A light guide plate provided in the housing and formed with a plurality of recesses having a reflection surface that reflects light from the light source to a surface side of the housing that is an image display surface. machine.   The device according to claim 1, wherein a portion of the housing where the image is displayed is translucent.   The apparatus according to claim 2, wherein a black sheet is provided below the light guide plate. Comprising a plurality of the light sources;
The said light-guide plate is formed with several recessed parts which have the reflective surface which reflects the light from any one of these light sources to the said housing | casing side. machine.   The apparatus according to claim 4, further comprising a plurality of light guide plates corresponding to each of the plurality of light sources.   The apparatus according to claim 5, wherein a black sheet is provided below the plurality of light guide plates.   The said recessed part is arrange | positioned so that any 1 or more combination of a character, a symbol, a figure, and a pattern may be displayed on the said display surface. The equipment described.   The device according to any one of claims 1 to 7, wherein the concave portion is formed by a dot-shaped notch formed in the light guide plate.   The device according to any one of claims 1 to 8, wherein an angle of the reflection surface of the concave portion with respect to a surface on which the light source is formed is 45 degrees or more and 60 degrees or less.   The device according to any one of claims 1 to 9, wherein the concave portion has a substantially rectangular shape in a plan view and has an aspect ratio in a range of 10: 1 to 1: 1.   The device according to claim 1, wherein the light source is formed to extend along an extending direction of the light guide plate.   The apparatus according to claim 11, wherein the light source is a light emitting diode in which a plurality of light emitting diodes are arranged in a predetermined direction.   13. The process according to claim 1, wherein a process of suppressing reflection of the light is performed on a surface of the light guide plate facing a surface on which the light is incident. Equipment.

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