JP6975603B2 - Luminescent device - Google Patents

Description

The present invention, light-emitting diodes: it relates to a light-emitting equipment having a light-emitting element (Light Emitting Diode LED) or the like.

Conventionally, as a kind of light emitting device, one having a light emitting element such as an LED is known. FIG. 10 shows a block circuit diagram of a basic configuration of a light emitting device provided with a light emitting element substrate LT on which a light emitting element is mounted. Further, a circuit diagram of one light emitting element 14 and a light emitting control unit 22 in FIG. 10 is shown in FIG. 11 (a), and a cross-sectional view taken along line C1-C2 of FIG. 11 (a) is shown in FIG. 11 (b). The light emitting device intersects the substrate 1 made of a glass substrate or the like, the scanning signal line 2 arranged in a predetermined direction (for example, the row direction) on the substrate 1, and the scanning signal line 2 in a predetermined direction. A light emitting control signal line 3 arranged in a direction (for example, a column direction) and a display unit 11 composed of a plurality of pixel units (Pmn) 15 separated by a scanning signal line 2 and a light emitting control signal line 3 are provided. It is a structure to have. The scanning signal line 2 and the light emitting control signal line 3 are electrically connected to a driving element such as an IC or an LSI on the back surface of the board 1 or outside the light emitting device via the side wiring 1s arranged on the side surface of the substrate 1. Be connected. Alternatively, the scanning signal line 2 and the light emitting control signal line 3 are electrically connected to the adjacent light emitting device via the side wiring 1s, and the plurality of light emitting devices are configured to be driven in conjunction with each other. Then, the display of one light emitting device or a plurality of light emitting devices is driven and controlled by the drive element 6.

When the drive element is installed on the back surface of the substrate 1, the drive element is mounted on the back surface of the substrate 1 by means such as a COG (Chip On Glass) method. In that case, a flexible printed circuit board (FPC) for inputting / outputting a drive signal, a control signal, etc. to and from the drive element via a lead wire may be installed on the back surface of the substrate 1. .. Further, a through conductor such as a through hole may be used instead of the side wiring 1s.

A light emission control unit 22 for controlling light emission, non-light emission, light emission intensity, etc. of the light emitting element 14 (LDmn) is arranged in each pixel unit 15 (Pmn). The light emission control unit 22 includes a thin film transistor (TFT) 12 (shown in FIG. 11A) as a switch element for inputting a light emission signal to each of the light emission elements 14, and a light emission control signal (light emission control). Light emitting element from the potential difference (light emitting signal) between the positive voltage (anode voltage: about 3 to 5V) and the negative voltage (cathode voltage: about -3V to 0V) according to the level (voltage) of the signal line 3). A TFT 13 (shown in FIG. 11A) as a driving element for driving the 14 with a current is included. A capacitive element 43 (shown in FIG. 11A) is arranged on the connection line connecting the gate electrode of the TFT 13 and the source electrode, and the capacitive element 43 is the voltage of the light emission control signal input to the gate electrode of the TFT 13. Functions as a holding capacity for holding the period until the next rewriting (a period of one frame).

The light emitting element 14 has a light emitting control unit 22, a positive voltage input line 16, and a negative voltage via through conductors 23a and 23b such as through holes penetrating the insulating layer 31 (shown in FIG. 11B) that covers the display unit 11. It is electrically connected to the voltage input line 17. That is, the positive electrode of the light emitting element 14 is connected to the positive voltage input line 16 via the through conductor 23a and the light emission control unit 22, and the negative electrode of the light emitting element 14 is connected to the negative voltage input line via the through conductor 23b. It is connected to 17.

11 (b) is a cross-sectional view taken along the line C1-C2 of FIG. 11 (a), and is a cross-sectional view showing through the portions of the TFT 13 and the light emitting element 14. As shown in FIG. 11B, a plurality of insulating layers 31 are arranged on the substrate 1, and a TFT 13 is provided between the layers of the plurality of insulating layers 31. In the plurality of insulating layers 31, the first insulating layer 31a, the second insulating layer 31b, the third insulating layer 31c, and the fourth insulating layer 31d are laminated in this order from the substrate 1 side, and the first insulating layer 31a and the second insulating layer 31a are laminated. The layer 31b and the third insulating layer 31c are made of silicon oxide (SiO ₂ ), silicon nitride (SiN _x ) and the like, respectively, and the fourth insulating layer 31d is made of an acrylic resin, polycarbonate and the like. A positive voltage input line 16 composed of a Mo layer / Al layer / Mo layer (indicating a laminated structure in which an Al layer and a Mo layer are sequentially laminated on the Mo layer) or the like is arranged on the substrate 1, and a positive voltage input is provided. The wire 16 is connected to the source electrode 13s of the TFT 13 via a through hole 52. The gate electrode 13g of the TFT 13 is arranged between the layers of the first insulating layer 31a and the second insulating layer 31b, and the semiconductor layer 13a of the TFT 13 is arranged between the layers of the second insulating layer 31b and the third insulating layer 31c. The source electrode 13s and the drain electrode 13d of the TFT 13 are arranged between the layers of the third insulating layer 31c and the fourth insulating layer 31d. The source electrode 13s is connected to the semiconductor layer 13a via a through hole 53, the drain electrode 13d is connected to the semiconductor layer 13a via a through hole 54, and the drain electrode 13d is connected to the electrode layer 42a constituting the positive electrode 44a. It is connected via a through hole 55.

The light emitting element 14 is electrically connected to the positive electrode 44a and the negative electrode 44b arranged on the insulating layer 31 via a conductive connecting member such as solder, and is mounted on the insulating layer 31. The positive electrode 44a is composed of an electrode layer 42a made of a Mo layer / Al layer / Mo layer or the like, and a transparent electrode 43a made of indium tin oxide (ITO) or the like covering the electrode layer 42a. The negative electrode 44b has the same configuration, and is composed of an electrode layer 42b made of Mo layer / Al layer / Mo layer and the like, and a transparent electrode 43b made of ITO or the like covering the electrode layer 42b. An insulating layer 45 is arranged so as to cover the insulating layer 31 and a part of each of the transparent electrodes 43a and 43b (the portion where the light emitting element 14 does not overlap), and the insulating layer 45 is silicon oxide (SiO ₂ ). , Silicon nitride (SiN _x ), etc.

12A and 12B show a headlight HL for an automobile having a light emitting element substrate LT, FIG. 12A is a front view of the headlight HL, and FIG. 12B is a cross-sectional view of the headlight HL. .. The headlight HL is a reflective member, a so-called reflector, made of a metal such as aluminum or stainless steel, an alloy, or a light reflecting layer made of silver or the like having a silvery tint on the surface of an insulating substrate such as plastic. 60, a base material 61 made of plastic or the like installed at the portion of the through hole 60k of the reflector 60, and a light emitting element substrate LT installed on the side of the first main surface 61a of the base material 61 by means such as adhesion. have. The reflector 60, the base material 61, and the light emitting element substrate LT are covered and sealed by a transparent cover body having a light collecting function (lens function), and are housed in the closed space. The base material 61 has a first main surface 61a on the side where the light emitting element substrate LT is installed, and a second main surface 61b facing the first main surface 61a. The first main surface 61a of the base material 61 has a shape curved in a convex shape so that the light 62 emitted from the light emitting element 14 on the light emitting element substrate LT has a certain radiation angle. Then, the second main surface 61b of the base material 61 covers the through hole 60k, and the peripheral edge portion of the second main surface 61b is attached to the reflector 60 by means of adhesion, screwing, engagement by protrusions and protrusion engagement holes, or the like. Will be done. Alternatively, the base material 61 is fitted into the through hole 60k and is fixed and installed by means such as adhesion.

Further, the base material 61 has a wiring 61L arranged on the surface and / or inside thereof, and the wiring 61L includes a light emitting element 14 mounted on a light emitting element substrate LT, a drive element 65 composed of an IC, an LSI, and the like. Electrically connect. When the wiring 61L is arranged on the surface of the base material 61, it is formed by a known plating method, a thick film forming method in which a conductor paste is applied and fired, a thin film forming method such as a CVD method, or the like. Further, when the wiring 61L is arranged inside the base material 61, for example, when the base material 61 is manufactured by the ceramic multilayer lamination technique, wiring is formed between the ceramic layers and a through conductor penetrating the ceramic layer is formed to form a ceramic. The wiring 61L is formed by connecting the wiring between the layers and the through conductor. An FPC 63 connected to the wiring 61L is installed on the side of the second main surface 61b of the base material 61 through the through hole 60k, and is wired via the FPC 63 to a storage space on the back surface side of the reflector 60 that is not visible from the outside. A drive element 65 or the like electrically connected to 61L is arranged. In the accommodation space, a circuit board 64 or the like on which a drive element 65 and an electronic element 66 such as a resistance element and a capacitance element are mounted and a circuit wiring is formed is arranged.

Yet another conventional example is a light emission system that includes two or more monolithic integrated light emitting elements, where each light emitting element in the two or more light emitting elements is an electroluminescent device and dedicated to driving it. At least one light emitting element in two or more light emitting elements includes a potential well for downward conversion of the light emitted by the electroluminescent device in the light emitting element, as proposed by a light emitting system. (See, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2010-525555

However, the conventional light emitting device having the configuration shown in FIGS. 10 to 12 has the following problems. As shown in FIG. 12, since one large-area light-emitting element substrate LT is installed on the base material 61, the heat generated by the light-emitting element 14 when the light-emitting element 14 on the light-emitting element substrate LT is driven. However, there is a problem that heat is easily stored in the central portion 61c of the base material 61. This is because the heat generated in the peripheral portion of the light emitting element substrate LT is easily dissipated by being transferred to the reflector 60, whereas the heat generated in the central portion of the light emitting element substrate LT is difficult to dissipate. Conceivable. Further, it is considered that the heat generated in the peripheral portion of the light emitting element substrate LT is also transferred to the central portion side of the light emitting element substrate LT, so that the heat tends to concentrate in the central portion of the light emitting element substrate LT. Be done. Further, when the light emitting element substrate LT is thinned, the temperature is different between the central portion and the peripheral portion, so that distortion and deformation occur due to thermal stress, and the insulating layer 31 constituting the light emitting element substrate LT (FIG. 11 (FIG. 11). There is a problem of deterioration in reliability that stress due to thermal stress is applied to b)) and delamination, cracks, etc. are likely to occur. Further, Patent Document 1 does not describe a configuration for solving various problems caused by the above-mentioned thermal stress.

The present invention has been completed in view of the above problems, and an object thereof is to suppress distortion and deformation of the light emitting element substrate due to thermal stress, and to suppress light emission due to stress due to thermal stress. It is intended to have high reliability and long life by suppressing delamination, cracks, etc. from occurring in the insulating layer constituting the element substrate.

The light emitting device of the present invention has a base material having a first main surface which is a curved surface shape or a polyhedron shape composed of a plurality of planes and a second main surface facing the first main surface, and the first of the base materials. (1) A plurality of light emitting element substrates installed on the main surface side and each having a plurality of light emitting elements mounted therein, the light emitting element substrate includes a thin film transistor for controlling lighting of the light emitting element, and the thin film transistor is provided. Includes a first thin film transistor provided on the light emitting element substrate in the central portion of the first main surface and a second thin film transistor provided on the light emitting element substrate on the peripheral portion of the first main surface. The resistance defined by the specific resistance, thickness, width, and length of the first semiconductor layer included in the first thin film transistor is the specific resistance of the second semiconductor layer included in the second thin film transistor. The configuration is smaller than the resistance defined by the thickness, width and length.

In the light emitting device of the present invention, preferably, the light emitting element substrate has wiring electrically connected to the light emitting element.

Further, in the light emitting device of the present invention, the first main surface is preferably curved in a convex shape.

Further, in the light emitting device of the present invention, the second main surface is preferably curved in a concave shape.

Further, in the light emitting device of the present invention, a heat radiating member is preferably installed on the side of the second main surface of the base material.

Further, the light emitting device of the present invention preferably has a brightness control device that controls the brightness of the light emitting element for each light emitting element substrate.

Further, in the light emitting device of the present invention, preferably, in the brightness control device, the brightness of the light emitting element substrate in the central portion of the first main surface of the base material is in the peripheral portion of the first main surface. The brightness is controlled to be equal to or lower than the brightness of the light emitting element substrate.

Further, in the light emitting device of the present invention, preferably, the plurality of the light emitting element substrates include one in the central portion of the first main surface and one in the peripheral portion, and in the central portion of the first main surface. The luminous efficiency of the first light emitting element mounted on the light emitting element substrate is higher than the luminous efficiency of the second light emitting element mounted on the light emitting element substrate in the peripheral portion of the first main surface.

Further, in the light emitting device of the present invention, preferably, the plurality of the light emitting element substrates have a space between adjacent to each other.

Further, in the light emitting device of the present invention, preferably, the plurality of the light emitting element substrates have a distance between the light emitting element substrate in the peripheral portion of the base material and the light emitting element substrate in the central portion of the base material. It is larger than the distance between the adjacent parts of the light emitting element substrate in the central portion, or larger than the distance between the adjacent parts of the light emitting element substrate in the peripheral portion.

Further, the light emitting device of the present invention includes a base material having a first main surface which is a curved surface shape or a polyhedron shape composed of a plurality of planes and a second main surface facing the first main surface, and the above-mentioned base material. The light emitting element substrate is provided with a plurality of light emitting element substrates installed on the side of the first main surface and each of which is equipped with a plurality of light emitting elements, and the light emitting element substrate includes a thin film transistor for controlling the lighting of the light emitting element. The thin film transistor includes a first thin film transistor provided on the light emitting element substrate in the central portion of the first main surface and a second thin film transistor provided on the light emitting element substrate on the peripheral portion of the first main surface. The electron mobility of the first semiconductor layer included in the first thin film transistor is higher than the electron mobility of the second semiconductor layer included in the second thin film transistor.

The light emitting device of the present invention has a base material having a first main surface which is a curved surface shape or a polyhedral shape composed of a plurality of planes and a second main surface facing the first main surface, and the first of the base materials. Since it has a configuration in which a plurality of light emitting element substrates are installed on the side of one main surface and each of which has a plurality of light emitting elements mounted therein, the following effects are obtained. Since a plurality of light emitting element substrates are installed on the side of the first main surface of the base material, heat transfer between the light emitting element substrates can be suppressed. That is, it is possible to suppress the heat generated in the light emitting element substrate in the peripheral portion of the base material from being transferred to the side of the light emitting element substrate in the central portion of the base material, and as a result, the light emitting element substrate in the central portion of the base material. It is possible to suppress the concentration of heat on the surface. Therefore, it is possible to prevent the light emitting element substrate from being distorted or deformed due to thermal stress. Further, it is possible to prevent delamination, cracks, etc. from occurring in the insulating layer constituting the light emitting element substrate due to stress due to thermal stress, and the light emitting device has high reliability.

In the light emitting device of the present invention, since the light emitting element substrate includes a thin film controlling the lighting of the light emitting element, the brightness is distributed to the light emitting device by controlling the brightness (light emitting intensity) of each light emitting element. It is also possible to control the brightness of the light emitting element so as to reduce the thermal stress.

Further, in the light emitting device of the present invention, when the base material has wiring electrically connected to the light emitting element, the base material functions not only as a support of the light emitting element substrate but also as a wiring substrate. Therefore, it becomes easy to control the brightness of the light emitting element.

Further, in the light emitting device of the present invention, since the first main surface has a curved surface shape or a polyhedral shape composed of a plurality of planes, the light emitted from the light emitting element is radiated in various directions including the immediately preceding side. In addition, the heat transfer path on the first main surface of the base material can be lengthened to prevent heat from concentrating on a specific portion.

Further, in the light emitting device of the present invention, when the first main surface is curved in a convex shape, the light emitted from the light emitting element can be emitted within a certain radiation angle range including the front. It will be more suitable as a headlight for vehicles and the like. In addition, the heat transfer path on the first main surface of the base material can be lengthened to prevent heat from concentrating on a specific portion.

Further, in the light emitting device of the present invention, when the second main surface is curved in a concave shape, heat transfer in the surface direction of the main surface of the base material is promoted and the surface area of the second main surface is increased. Therefore, the radiation of heat to the space on the side of the second main surface is promoted. As a result, it is possible to further suppress the concentration of heat in the central portion of the base material.

Further, in the light emitting device of the present invention, when the heat radiating member is installed on the side of the second main surface of the base material, the heat of the base material can be efficiently radiated by the heat radiating member.

Further, when the light emitting device of the present invention has a brightness control device that controls the brightness of the light emitting element for each of the light emitting element substrates, it becomes easier to impart a brightness distribution to the light emitting device and it is thermally. It is also possible to easily control the brightness of the light emitting element so as to reduce stress.

Further, in the light emitting device of the present invention, the plurality of the light emitting element substrates include one in the central portion of the first main surface and one in the peripheral portion, and the light emitting device in the central portion of the first main surface. When the luminous efficiency of the first light emitting element mounted on the element substrate is higher than the luminous efficiency of the second light emitting element mounted on the light emitting element substrate in the peripheral portion of the first main surface, the light emitting element is used. It becomes easy to make the emitted light have the highest brightness in the immediately preceding direction. In addition, it becomes easier to suppress the concentration of heat in the central portion of the base material.

Further, in the light emitting device of the present invention, the plurality of the light emitting element substrates include one in the central portion of the first main surface and one in the peripheral portion, and the light emitting device in the central portion of the first main surface. The resistance defined by the specific resistance, the thickness, the width, and the length of the first semiconductor layer included in the first thinning film provided on the element substrate is applied to the light emitting element substrate in the peripheral portion of the first main surface. Since it is smaller than the resistance defined by the specific resistance, the thickness, the width, and the length of the second semiconductor layer included in the provided second thin film, the light emitted from the light emitting element is the brightest in the immediately preceding direction. It becomes easy to make it high. In addition, it becomes easier to suppress the concentration of heat in the central portion of the base material.

Further, in the light emitting device of the present invention, the plurality of the light emitting element substrates include one in the central portion of the first main surface and one in the peripheral portion, and the light emitting device in the central portion of the first main surface. The electron mobility of the first semiconductor layer included in the first thin film transistor provided on the element substrate is included in the second thin film transistor provided on the light emitting element substrate on the peripheral portion of the first main surface. Since it is larger than the electron mobility of the semiconductor layer, it is easy to make the light emitted from the light emitting element have the highest brightness in the immediately preceding direction. In addition, it becomes easier to suppress the concentration of heat in the central portion of the base material.

1A, 1B, and 1C are views showing various examples of embodiments of the light emitting device of the present invention, respectively, and are front views of the light emitting device. 2 (a) and 2 (b) are views showing other examples of the embodiment of the light emitting device of the present invention, respectively, and are cross-sectional views taken along the line A1-A2 of FIG. FIG. 3 is a diagram showing another example of the embodiment of the light emitting device of the present invention, and is a cross-sectional view of the light emitting device. 4 (a) is a partially enlarged cross-sectional view of a portion B of FIG. 3, and FIG. 4 (b) is a partially enlarged cross-sectional view showing another example according to the same embodiment as (a). 5 (a) and 5 (b) are views showing another example of the embodiment of the light emitting device of the present invention, respectively, and are sectional views of the light emitting device. 6 (a) and 6 (b) are views showing another example of the embodiment of the light emitting device of the present invention, respectively, and are sectional views of the light emitting device. 7 (a) and 7 (b) are views showing another example of the embodiment of the light emitting device of the present invention, respectively, and are sectional views of the light emitting device. 8 (a) and 8 (b) are views showing another example of the embodiment of the light emitting device of the present invention, respectively, and are sectional views of the light emitting device. FIG. 9 is a diagram showing another example of the embodiment of the light emitting device of the present invention, and is a cross-sectional view of the light emitting device. FIG. 10 is a diagram showing an example of a light emitting element substrate included in a conventional light emitting device, and is a block circuit diagram of a light emitting element, a light emitting control unit, wiring, and the like arranged on the light emitting element substrate. 11 (a) is a circuit diagram of one light emitting element in the light emitting element substrate of FIG. 10 and a light emitting control unit connected to the light emitting element, and FIG. 11 (b) is a cross-sectional view taken along line C1-C2 of (a). 12 (a) and 12 (b) are views showing an example of a vehicle headlight using the light emitting element substrate of FIG. 10, (a) is a front view of the vehicle headlight, and (b) is a front view. It is sectional drawing of the headlight for a vehicle.

Hereinafter, embodiments of the light emitting device, the headlight for a vehicle, and the vehicle of the present invention will be described with reference to the drawings. However, each figure referred to below shows the main part for explaining the light emitting device and the like among the constituent members in the embodiment of the light emitting device and the like of the present invention. Therefore, the light emitting device or the like according to the present invention may include well-known components such as wiring conductors, circuit boards, control ICs, and LSIs (not shown in the figure). In FIGS. 1 to 9 showing an embodiment of a vehicle headlight as a light emitting device of the present invention, the same parts as those in FIGS. 10 to 12 are designated by the same reference numerals, and detailed description thereof will be given. Omit. Further, the light emitting device of the present invention is not limited to vehicle headlights, but various self-luminous display devices such as LED display devices, organic EL display devices, and inorganic EL display devices, indoor lighting devices, and outdoor lighting. It can be applied to devices, lighting devices inside or outside vehicles such as automobiles, traffic lights, and the like.

The light emitting device of the present invention has, for example, the headlights HL, HLa, HLb shown in FIGS. 1 (a), 1 (b), and (c), and as shown in FIG. A plurality of base materials 61 having a first main surface 61a and a second main surface 61b facing the first main surface 61a and a plurality of base materials 61 installed on the side of the first main surface 61a, each of which is equipped with a plurality of light emitting elements. It is a configuration having the light emitting element substrates LT1 to LT12. This configuration produces the following effects. Since a plurality of light emitting element substrates LT1 to LT12 are installed on the side of the first main surface 61a of the base material 61, heat transfer between the light emitting element substrates LT1 to LT12 can be suppressed. That is, the heat generated in the light emitting element substrate (for example, the light emitting element substrate LT1, LT6, LT7, LT12) in the peripheral portion of the base material 61 is the heat generated in the light emitting element substrate (for example, the light emitting element substrate LT2-) in the central portion of the base material 61. It is possible to suppress heat transfer to the side of LT5, LT8 to LT11), and as a result, it is possible to suppress heat concentration on the light emitting element substrate in the central portion of the base material 61. Therefore, it is possible to prevent distortion and deformation of the light emitting element substrates LT1 to LT12 due to thermal stress. Further, it is possible to prevent delamination, cracks, etc. from occurring in the insulating layers constituting the light emitting element substrates LT1 to LT12 due to stress due to thermal stress, and the light emitting device has high reliability.

Further, as shown in FIG. 1 (b), a plurality of light emitting element substrates LT1 to LT6 are installed on the side of the first main surface 61a of the base material 61, and the light emitting element substrates LT1 in the peripheral portion of the base material 61 are installed. The distance between the LT4 and the light emitting element substrate LT2, LT3, LT5, LT6 in the central portion of the base material 61 is larger than the distance between the adjacent light emitting element substrates LT2, LT3, LT5, LT6 in the central portion of the base material 61. It may be a large configuration. In this case, it is possible to further suppress the heat generated in the light emitting element substrates LT1 and LT4 in the peripheral portion of the base material 61 from being transferred to the side of the light emitting element substrates LT2, LT3, LT5 and LT6 in the central portion of the base material 61. As a result, it is possible to further suppress the concentration of heat on the light emitting element substrates LT2, LT3, LT5, and LT6 in the central portion of the base material 61. Such a configuration is such that the light emitting element substrate LT1 in the peripheral portion of the base material 61 is provided.
, The more effective configuration is when the amount of heat generated in each of LT4 is larger than the amount of heat generated in each of the light emitting element substrates LT2, LT3, LT5, and LT6 in the central portion of the base material 61.

Further, as shown in FIG. 1 (c), a plurality of light emitting element substrates LT1 to LT5 are installed on the side of the first main surface 61a of the base material 61, and the light emitting element substrates LT1 in the peripheral portion of the base material 61 are installed. The distance between the LT2, LT3, LT4 and the light emitting element substrate LT5 in the central portion of the base material 61 is larger than the distance between the adjacent parts of the light emitting element substrates LT1, LT2, LT3, LT4 in the peripheral portion of the base material 61. It is also good. In this case, the diffusion of heat generated in the plurality of light emitting element substrates LT1 to LT5 is promoted. That is, the number of the light emitting element substrates LT1, LT2, LT3, LT4 in the peripheral portion of the base material 61, which is close to the reflector 60 that can also function as a heat radiating member, is the number of the light emitting element substrate LT5 in the central portion of the base material 61. Being more than the number also contributes to improving heat dissipation. Therefore, it is possible to further suppress the concentration of heat on the light emitting element substrate LT5 in the central portion of the base material 61.

In the light emitting device of the present invention, it is preferable that the plurality of light emitting element substrates LT1 to LT12 have an interval between their adjacencies. In this case, heat transfer between the plurality of light emitting element substrates LT1 to LT12 can be further suppressed. The interval is preferably 5 mm or more, more preferably about 10 mm or more. If it is less than 5 mm, the effect of suppressing heat transfer between the plurality of light emitting element substrates LT1 to LT12 tends to decrease.

The base material 61 is made of a metal such as glass, plastic, ceramic, aluminum or copper, an alloy such as stainless steel or a copper-zinc alloy or the like. When the light emitting device is applied to a high-intensity lighting device such as a headlight for a vehicle, the base material 61 is preferably a color having good light reflectivity such as white, silver, silver-white, and gold. .. Further, the base material 61 may be a composite substrate in which a plurality of types of substrates among a glass substrate, a plastic substrate, a ceramic substrate, a metal substrate and an alloy substrate are laminated. When the base material 61 is a composite substrate including a metal substrate and an alloy substrate, heat dissipation is improved, which is preferable.

The substrate 1 constituting the light emitting element substrate LT is opaque white glass such as glass and frosted glass, glass colored in white and the like, plastic, ceramic, translucent ceramic, metal such as aluminum and copper, stainless steel and copper. -Consists of alloys such as zinc alloys. When the light emitting device is applied to a high-intensity lighting device such as a headlight for a vehicle, the substrate 1 is preferably a color having good light reflectivity such as white.

In the light emitting device of the present invention, as the light emitting element, any self-luminous element such as a microchip type light emitting diode (LED), a monolithic type light emitting diode, an organic EL, an inorganic EL, or a semiconductor laser element can be adopted. ..

The light emitting element can be suitably used as a lighting device such as a headlight for vehicles as long as it is a light emitting element that emits white light, but is not limited to the light emitting element that emits white light, for example, a light emitting element that emits red light. It may be a 14R (emission wavelength of about 660 nm), a light emitting element 14G (emission wavelength of about 520 nm) that emits green light, a light emitting element 14B (emission wavelength of about 450 nm) that emits blue light, and further emits yellow light. It may be a light emitting element, a light emitting element that emits lantern light, a light emitting element that emits purple light, or the like. When the light emitting device of the present invention is used as a display device, it may be provided with light emitting elements 14R, 14G, 14B of the three primary colors. When the light emitting device is made of an LED, the light emitting portion of the light emitting device 14R is made of a material such as aluminum gallium arsenide (AlGaAs), gallium arsenide phosphorus (GaAsP), gallium phosphide (GaP), and a perovskite semiconductor. Similarly, the light emitting portion of the light emitting element 14G includes indium gallium nitride (InGaN), gallium nitride (GaN), aluminum gallium nitride (AlGaN), and gallium phosphide (G).
It is composed of materials such as aP), zinc selenide (ZnSe), aluminum indium gallium phosphide (AlGaInP), and perovskite semiconductor. Similarly, the light emitting portion of the light emitting element 14B is made of a material such as indium gallium nitride (InGaN), gallium nitride (GaN), aluminum gallium nitride (AlGaN), and zinc selenide (ZnSe).

The non-planar first main surface 61a of the base material 61 has a purpose of radiating light emitted from a light emitting element in various directions including the immediately preceding direction, and has a long heat transfer path in the first main surface 61a of the base material 61. The purpose is to prevent heat from concentrating on a specific part. Therefore, the non-planar first main surface 61a of the base material 61 has a curved surface shape or a polyhedral shape composed of a plurality of planes. For example, the first main surface 61a has a convex curved shape as shown in FIG. 2A, and has a convex partial spherical surface, a convex partial elliptical surface, a convex partial cylindrical surface, and a convex shape. It may be a convex curved surface shape such as a partial hyperboloid. Further, the first main surface 61a has a convex curved shape as shown in FIG. 2B, and has a convex polyhedral shape. As a whole, the convex partial spherical surface and the convex partial ellipse are formed. It may have a shape such as a body surface, a convex partial cylindrical surface, or a convex partial hyperboloid. The polyhedral shape is suitable in that it is easy to form an approximate curved surface by a mechanical processing apparatus such as a cutting apparatus. When the main surface 61a has the shape shown in FIG. 2, the light emitted from the light emitting elements mounted on the light emitting element substrates LT1 to LT12 has a certain radiation angle as a whole, for example, ± 45 ° with respect to the radiation center axis LA1. It can be radiated within the range of the radiation angle of about (θ = 45 °) (within the range of the radiation axes L2 to L3). Such a shape of the first main surface 61a is suitable for vehicle headlights, traffic lights, lighting devices, and the like. In FIG. 2A, the reference numerals LA12 and LA13 are directions parallel to the radiation center axis LA1, respectively.

Further, the first main surface 61a has a concavely curved shape as shown in FIG. 5A, and has a concave partial spherical surface, a concave partial elliptical surface, a concave partial cylindrical surface, and a concave shape. It may be a concave curved surface shape such as a partial hyperboloid. Further, the first main surface 61a has a concavely curved shape as shown in FIG. 5B, has a concave polyhedral shape, and has an overall concave partial spherical surface and a concave partial elliptical surface. , A concave partial cylindrical surface, a concave partial hyperboloid, or the like may be used. When the main surface 61a has the shape shown in FIG. 5, the light radiated from the light emitting elements mounted on the light emitting element substrates LT1 to LT12 can be condensed. Such a shape of the first main surface 61a is suitable for a vehicle headlight, a lighting device, or the like that concentrates light on a spot.

Further, the first main surface 61a may have a shape in which a convexly curved shape and a concavely curved shape as shown in FIG. 6A are connected, that is, a so-called S-shaped shape. The convexly curved shape may be a convex curved surface shape such as a convex partial spherical surface, a convex partial elliptical surface, a convex partial cylindrical surface, and a convex partial hyperboloid. The concavely curved shape may be a concave curved surface such as a concave partial spherical surface, a concave partial elliptical surface, a concave partial cylindrical surface, or a concave partial hyperboloid. Further, the first main surface 61a has an S-shaped shape as shown in FIG. 6B, and the convexly curved shape has a convex partial spherical surface and a convex partial elliptical surface as a whole. It is a convex polyhedral shape with a convex partial cylindrical surface, a convex partial hyperboloid, etc., and the concave curved shape is a concave partial spherical surface and a concave partial ellipse as a whole. It may be a concave polyhedral shape having a body surface, a concave partial cylindrical surface, a concave partial hyperboloid, or the like. When the main surface 61a has the shape shown in FIG. 6, the light radiated from the light emitting elements mounted on the light emitting element substrates LT1 to LT12 can be condensed. Such a shape of the first main surface 61a is suitable for a headlight for a vehicle, a lighting device, or the like having both diffusivity and light-collecting property.

As shown in FIG. 7, it is preferable that the first main surface 61a of the base material 61 is curved in a convex shape and the second main surface 61b is curved in a concave shape. In this case, heat transfer in the plane direction of the first main surface 61a and the second main surface 61b of the base material 61 is promoted, and the surface area of the second main surface 61b increases, so that the side of the second main surface 61b is on the side. Radiation of heat to the space is promoted. As a result, it is possible to further suppress the concentration of heat in the central portion of the base material 61. In FIG. 7A, the first main surface 61a of the base material 61 is a convex curved surface such as a convex partial spherical surface, a convex partial elliptical surface, a convex partial cylindrical surface, and a convex partial hyperboloid. It is a shape, and shows a configuration in which the second main surface 61b is a concave curved surface shape such as a concave partial spherical surface, a concave partial elliptical surface, a concave partial cylindrical surface, and a concave partial hyperboloid. There is. In FIG. 7B, the first main surface 61a of the base material 61 has a convex partial spherical surface, a convex partial elliptical surface, a convex partial cylindrical surface, a convex partial hyperboloid, and the like. It has a convex polyhedral shape, and the second main surface 61b has a concave shape such as a concave partial spherical surface, a concave partial elliptical surface, a concave partial cylindrical surface, and a concave partial hyperboloid. The configuration which is a polyhedral shape is shown.

In the light emitting device of the present invention, as shown in FIGS. 10 and 11, the light emitting element substrate LT is a thin film transistor (TFT) 12 and 13 that control the lighting of the light emitting element 14.
It is equipped with. Thereby, by controlling the luminance (luminance intensity) of each light emitting element 14, the luminance distribution can be given to the light emitting device, and the luminance of the light emitting element 14 is controlled so as to reduce the thermal stress. You can also.

Further, in the light emitting device of the present invention, as shown in FIG. 9, it is preferable that the base material 61 has a wiring 61L electrically connected to the light emitting element. In this case, since the base material 61 functions not only as a support for the light emitting element substrate LT but also as a wiring board, it becomes easy to control the brightness of the light emitting element. The wiring 61L is arranged on the surface and / or inside of the base material 61, and the wiring 61L electrically connects the light emitting element mounted on the light emitting element substrate LT and the driving element 65 composed of an IC, an LSI, or the like. do. When the wiring 61L is arranged on the surface of the base material 61, when the base material 61 is made of an insulating material such as plastic, a known plating method, a thick film forming method in which a conductor paste is applied and fired, a thin film such as a CVD method, etc. It can be formed by a forming method or the like. Further, when the wiring 61L is arranged inside the base material 61, for example, when the base material 61 is manufactured by the ceramic multilayer lamination technique, wiring is formed between the ceramic layers and a through conductor penetrating the ceramic layer is formed to form a ceramic. The wiring 61L can be formed by connecting the wiring between the layers and the through conductor.

Further, it is preferable that the light emitting device of the present invention has a brightness control device that controls the brightness of the light emitting element for each light emitting element substrate LT. In this case, it becomes easier to impart a luminance distribution to the light emitting device, and it is also possible to easily control the luminance of the light emitting element so as to reduce thermal stress. For example, in the case of the configuration shown in FIG. 9, the luminance control device corresponds to the drive element 65. The drive element 65 is electrically connected to each of the light emitting element substrates LT1 to LT12 via the FPC 63 and the wiring 61L, and controls the brightness of the light emitting element mounted on each of the light emitting element substrates LT1 to LT12. This luminance control device may be a drive element such as an IC or LSI separate from the drive element 65, or may be a drive element arranged in the FPC 63. Further, in this case, when a plurality of light emitting elements are mounted on each of the light emitting element substrates LT1 to LT12, the brightness of each of the plurality of light emitting elements may be further controlled. In that case, it becomes easy to give a fine luminance distribution by the light emitting device, and it becomes easier to control the luminance of the light emitting element so as to reduce the thermal stress.

When the brightness of the light emitting element is controlled so as to reduce the thermal stress, the light emitting element substrate LT (for example, the light emitting element substrate LT2 to LT5, LT8 to LT11) in the central portion of the first main surface 61a of the base material 61 is individually controlled. It is possible to control the brightness of the base material 61 to be equal to or less than the individual brightness of the light emitting element substrate LT (for example, the light emitting element substrate LT1, LT6, LT7, LT12) in the peripheral portion of the first main surface 61a of the base material 61. can. That is, the individual calorific value of the light emitting element substrate LT in the central portion of the first main surface 61a of the base material 61 is equivalent to the individual calorific value of the light emitting element substrate LT in the peripheral portion of the first main surface 61a of the base material 61. Since the following, it becomes difficult for heat to concentrate in the central portion of the base material 61, and thermal stress is reduced.

When the central portion of the first main surface 61a of the base material 61 has a configuration in which the light emitting element substrate LT is arranged long in a certain direction (horizontal direction in FIG. 1) as shown in FIG. 1, the first main surface 61a Assuming that the length in the lateral direction is LY, from the part having a length of about −0.15LY to +0.15LY with respect to the center of the first main surface 61a (the part having a total length of about 0.3LY). It is a portion having a length of about −0.35LY to +0.35LY with respect to the center of the first main surface 61a (a portion having a total length of about 0.7LY). Therefore, the peripheral portion of the first main surface 61a of the base material 61 is a residual portion of the central portion, and is a portion having a length of about 0.35LY to 0.15LY from the end of the first main surface 61a (in total). A portion having a length of 0.7LY to 0.3LY). Further, when the shape of the first main surface 61a is a substantially isotropic shape such as a square shape or a circular shape, the central portion of the first main surface 61a is the first, assuming that the area of the first main surface 61a is S. 1 It is a similar-shaped portion having an area of about 0.3S to 0.7S centered on the center point of the main surface 61a. Therefore, the peripheral portion of the first main surface 61a of the base material 61 is a portion of about 0.7S to 0.3S remaining in the central portion.

Further, in the light emitting device of the present invention, as shown in FIG. 8, it is preferable that the heat radiating member 63 is installed on the side of the second main surface 61b of the base material 61. In this case, the heat of the base material 61 can be efficiently dissipated by the heat radiating member 63. FIG. 8A shows a configuration having a plate-shaped heat radiating member 63 made of a metal having good thermal conductivity such as copper, aluminum, stainless steel, an alloy, or the like, and FIG. 8B shows the above-mentioned thermal conductivity. Shown shows a configuration having a heat radiating member 63 made of a metal, an alloy, or the like having good properties and having heat radiating fins. In the configuration of FIG. 8, when the light emitting device is a vehicle headlight having the reflector 60 shown in FIG. 9, in order to improve the heat transfer property from the heat radiating member 63 to the reflector 60, the light emitting device and the reflector 60 in the heat radiating member 63 are used. It is preferable that the thickness of the contact portion is thinner than the thickness of other portions. That is, as compared with the case where the thickness of the contact portion of the heat radiating member 63 with the reflector 60 is the same as the thickness of other portions, the transmission from the light emitting element substrates LT1 and LT6 in the peripheral portion of the base material 61 to the reflector 60. This is because the heat path becomes shorter.

Further, in the light emitting device of the present invention, the plurality of light emitting element substrates LT1 to LT12 are located in the central portion of the first main surface 61a (for example, the light emitting element substrates LT2 to LT5, LT8 to LT11) and those in the peripheral portion (for example). For example, the light emitting element substrate LT1, LT6, LT7, LT12) is included, and the luminous efficiency of the first light emitting element mounted on the light emitting element substrates LT2 to LT5, LT8 to LT11 in the central portion of the first main surface 61a. However, it is preferable that the luminous efficiency is higher than that of the second light emitting element mounted on the light emitting element substrates LT1, LT6, LT7, and LT12 in the peripheral portion of the first main surface 61a. In this case, the drive power supplied to the first light emitting element mounted on the light emitting element substrates LT2 to LT5, LT8 to LT11 in the central portion of the first main surface 61a, and the light emission in the peripheral portion of the first main surface 61a. Even if the driving power supplied to the second light emitting element mounted on the element substrates LT1, LT6, LT7, LT12 is the same, the brightness of the first light emitting element becomes higher than the brightness of the second light emitting element. .. That is, it becomes easy to make the light emitted from the light emitting element group have the highest brightness in the immediately preceding direction. This is advantageous for vehicle headlights and the like, where visibility in front of the vehicle is important. The brightness of the first light emitting element can be made higher than the brightness of the second light emitting element without making the driving power supplied to the first light emitting element larger than the driving power supplied to the second light emitting element. Therefore, it becomes easier to suppress the concentration of heat in the central portion of the base material 61.

When the light emitting element is an LED, the external quantum efficiency as the light emitting efficiency is represented by (external quantum efficiency ηe) = (internal quantum efficiency ηi) × (light extraction efficiency E). The improvement of the internal quantum efficiency ηi can be achieved mainly by improving the pn junction. For example, the pn junction can be improved by improving the crystallinity of the p layer, the light emitting layer and the n layer, for example, by reducing the transition density of the crystal. Further, the pn junction can be improved by improving the heterojunction structure of the pn junction, for example, by changing the single heterojunction structure to a double heterojunction structure. Further, the pn junction can be improved by improving the quantum well structure of the pn junction, for example, by eliminating the distortion of the quantum well structure and increasing the overlap between electrons and holes to improve the recombination efficiency. It can be carried out. Furthermore, by improving the electron injection efficiency into the light emitting layer, for example, by improving the hole concentration in the p layer,
The pn junction can be improved.

In order to improve the light extraction efficiency E, it can be performed by means such as removal of the light absorbing portion in the LED and reduction of the internal multiple reflection portion in the LED. In order to remove the light absorbing portion in the LED, there is a means such as using a transparent substrate as a substrate constituting the LED. In order to reduce the internal multiple reflection portion in the LED, there is a means such as roughening the surface of the reflection portion.

Therefore, by adjusting at least one of the internal quantum efficiency ηi and the light extraction efficiency E so that the first light emitting element is higher than the second light emitting element, the light emitting efficiency of the first light emitting element becomes the first. It can be set to be higher than the luminous efficiency of the light emitting element of 2.

Further, in the light emitting device of the present invention, the plurality of light emitting element substrates LT1 to LT12 are located in the central portion of the first main surface (for example, the light emitting element substrates LT2 to LT5, LT8 to LT11) and those in the peripheral portion (for example). , Luminous element substrate LT1, LT6, LT7, LT12), and the first TFT included in the light emitting element substrate LT2 to LT5, LT8 to LT11 provided in the central portion of the first main surface 61a. The resistance of the semiconductor layer is smaller than the resistance of the second semiconductor layer included in the second TFT included in the light emitting device substrates LT1, LT6, LT7, and LT12 provided in the peripheral portion of the first main surface 61a. This makes it easy to make the light emitted from the light emitting element have the highest brightness in the immediately preceding direction. Further, it becomes easier to suppress the concentration of heat in the central portion of the base material 61.

When the resistivity of the two semiconductor layers is the same (ρ: inversely proportional to the electron mobility), the thickness (St), width (Sw), and length of the strip-shaped semiconductor layer are the same. Specified by S (Sl). If Sw and Sl of the two semiconductor layers are the same, the thicker the St, the smaller the resistance of the semiconductor layer. If the St and Sl of the two semiconductor layers are the same, the wider the Sw, the smaller the resistance of the semiconductor layer. If the St and Sw of the two semiconductor layers are the same, the shorter the Sl, the smaller the resistance of the semiconductor layer. If St, Sw, and Sl of the two semiconductor layers are the same, the smaller the resistivity ρ, the smaller the resistance of the semiconductor layer. Therefore, by adjusting St, Sw, Sl, and ρ of the first semiconductor layer and the second semiconductor layer, the resistance of the first semiconductor layer becomes smaller than the resistance of the second semiconductor layer. Set to. In order to reduce the ρ of the semiconductor layer, for example, the density of electrons and holes (carriers) contained in the semiconductor layer, that is, the so-called carrier density, may be increased.

Further, in the light emitting device of the present invention, the plurality of light emitting element substrates LT1 to LT12 are located in the central portion of the first main surface 61a (for example, the light emitting element substrates LT2 to LT5, LT8 to LT11) and those located in the peripheral portion (for example). For example, the light emitting element substrate LT1, LT6, LT7, LT12) is included, and the first TFT included in the light emitting element substrate LT2 to LT5, LT8 to LT11 provided in the central portion of the first main surface 61a. The electron mobility of the semiconductor layer is higher than the electron mobility of the second semiconductor layer included in the second TFT provided on the light emitting device substrates LT1, LT6, LT7, LT12 provided in the peripheral portion of the first main surface 61a. big. This makes it easy to make the light emitted from the light emitting element have the highest brightness in the immediately preceding direction. Further, it becomes easier to suppress the concentration of heat in the central portion of the base material 61.

As described above, in order to set the electron mobility of the first semiconductor layer to be larger than the electron mobility of the second semiconductor layer, the carrier density of the first semiconductor layer is set to be higher than that of the second semiconductor layer. It may be set so as to be larger than the carrier density of. Further, the first semiconductor layer is not limited to the means for adjusting the carrier density, and the first semiconductor layer is made of low-temperature Poly Silicon (LTPS), and the second semiconductor layer is made of amorphous silicon. It is also possible to adopt the means of making it. This is because the electron mobility of LTPS is 100 to ^{200 cm 2} / Vs or more, which is much higher than that of amorphous silicon of about 0.5 cm 2 / Vs.

As shown in FIGS. 3, 4 (a) and 4 (b), the light emitting device of the present invention has a base material having a non-planar first main surface 61a and a second main surface 61b facing the first main surface 61a. It has a light emitting element substrate LT3 which is installed on the side of the first main surface 61a of the base material 61 and mounts a light emitting element, and is a portion between the light emitting element substrate LT3 and the base material 61. It is a configuration in which there is a gap 70 that exists in a target manner. Due to this configuration, since there is a gap 70 partially existing between the light emitting element substrate LT3 and the base material 61, the surface area exposed in the space of the light emitting element substrate LT3 is increased, and the surface area of the light emitting element substrate LT3 is increased. Heat dissipation is improved.

As shown in FIGS. 4A and 4B, a part of the main surface of the light emitting element substrate LT3 on the base material 61 side is the first main surface of the base material 61 via a fixing member 71 such as an adhesive. It is fixed to 61a. As a result, there is a gap 70 that partially exists between the light emitting element substrate LT3 and the base material 61. FIG. 4A shows a configuration in which the central portion of the main surface of the light emitting element substrate LT3 on the base material 61 side is fixed to the base material 61 by a fixing member 71, and FIG. 4B shows the light emitting element substrate LT3. The edge of the main surface of the base material 61 side is fixed to the base material 61 by the fixing member 71. In the configuration of FIG. 4B, the fixing member 71 may be arranged over the entire circumference of the edge of the main surface of the light emitting element substrate LT3 on the base material 61 side, but is arranged on the base material 61 side of the light emitting element substrate LT3. Multiple pieces are arranged at intervals on the edges of the main surface of the. As a result, outside air enters and circulates on the main surface of the light emitting element substrate LT3 on the base material 61 side, so that the light emitting element substrate LT3 is efficiently dissipated to the space. One light emitting element substrate LT having such a configuration may be present on the base material 61, but as shown in FIG. 3, a plurality of light emitting element substrates LT1 to LT12 may have the above configuration. Further, the fixing member 71 may be made of a resin material or the like containing metal fine particles such as silver particles having excellent thermal conductivity. In this case, the heat generated by the light emitting element substrate LT3 can be efficiently dissipated to the base material 61. Further, in order to further improve the heat dissipation of the light emitting element substrate LT3, a blower such as a blower fan for blowing cooling air may be provided on the light emitting element substrate LT3.

In the light emitting device having the configuration of FIG. 3, a plurality of light emitting element substrates LT1 to LT12 are installed on the side of the first main surface 61a of the base material 61, and each light emitting element substrate LT is equipped with a plurality of light emitting elements. At the same time, it is preferable to have a TFT that controls the lighting of the light emitting element. In this case, by controlling the brightness of the light emitting element mounted on each light emitting element substrate LT, the brightness distribution can be given to the light emitting device, and the brightness of the light emitting element is controlled so as to reduce the thermal stress. You can also do it.

The light emitting device of the present invention can be applied to a display device or the like. The display device to which the light emitting device of the present invention is applied has a configuration in which a plurality of light emitting elements 14 having different light emitting wavelengths (light emitting colors) are arranged in one pixel unit 15, and a light emitting control unit 22 connected to each is provided. May be. For example, a red light emitting element composed of a red LED (RLED) or the like, a green light emitting element composed of a green LED (GLED) or the like, and a blue light emitting element composed of a blue LED (BLED) or the like are arranged in one pixel unit 15. There may be a configuration in which there are light emission control units (R driver, G driver, B driver) connected to each. In this case, for example, the RLED, GLED, and BLED are collectively arranged at each vertex of the equilateral triangle in the center of the pixel portion 15, and the R driver, the G driver, and the B driver are the RLED and the GLED. It may be configured to be arranged inside the substrate 1 with respect to the BLED. Further, the RLEDs, GLEDs, and BLEDs are arranged in the center of the pixel unit 15 on a straight line parallel to the scanning signal line 2 or the light emission control signal line 3, that is, on a straight line parallel to the row direction or the column direction. You can also do it.

Further, the light emitting elements 14 having different emission wavelengths (emission colors) are arranged in each of the three adjacent pixel units 15, and the light emission control unit 22 connected to each of them may be provided. For example, a red light emitting element composed of a red LED (RLED) or the like is arranged in the first pixel unit 15, a green light emitting element composed of a green LED (GLED) or the like is arranged in the second pixel unit 15, and a third pixel. Even if a blue light emitting element composed of a blue LED (BLED) or the like is arranged in the unit 15, and a light emitting control unit (R driver, G driver, B driver) connected to each is provided in each pixel unit 15. good. The first pixel unit 15, the second pixel unit 15, and the third pixel unit 15 may be arranged in the row direction or may be arranged in the column direction.

The vehicle headlight of the present invention is configured to have the light emitting device having the above-described configuration of the present invention. This configuration provides high reliability and long life. For example, the vehicle headlight HL of the present invention includes a reflector 60 as shown in FIG. The reflector 60 is made of a metal such as aluminum or stainless steel or an alloy, or a light reflecting layer made of silver or aluminum having a silvery tint is formed on the surface of an insulating substrate such as plastic. The reflector 60, the base material 61, and the light emitting element substrates LT1 to LT12 are covered and sealed with a transparent coating body made of glass, plastic, etc., which has a condensing function, that is, a lens function such as a Fresnel lens, and is hermetically sealed. It is housed in the space.

The vehicle of the present invention is configured to have a headlight for a vehicle having the above-described configuration of the present invention. With this configuration, it has high reliability and long life vehicle headlights, which makes it a highly reliable and long life vehicle. Vehicles include automobiles, bicycles, motorcycles, buses, trucks, trains such as trains, ships, airplanes, and the like.

The light emitting device, the headlight for a vehicle, and the vehicle of the present invention are not limited to the above-described embodiment, and may be appropriately modified or improved.

As described above, the light emitting device of the present invention can be applied to display devices such as LED display devices and organic EL display devices. The display device can be applied to various electronic devices. The electronic devices include a complex and large display device (multi-display), an automobile route guidance system (car navigation system), a ship route guidance system, an aircraft route guidance system, a smartphone terminal, a mobile phone, a tablet terminal, and a personal digital assistant. (PDAs), video cameras, digital still cameras, electronic notebooks, electronic books, electronic dictionaries, personal computers, copying machines, game device terminals, televisions, product display tags, price display tags, industrial programmable display devices, Car audio, digital audio players, facsimiles, printers, automatic cash deposit / payment machines (ATMs), vending machines, head-mounted displays (HMDs), digital display watches, smart watches, etc.

1 Substrate 2 Scanning signal line 3 Light emission control signal line 12, 13 TFT
14 Light emitting element 16 Positive voltage input line 17 Negative voltage input line 31 Insulation layer 61 Base material 61a First main surface 61b Second main surface 61L Wiring

Claims (11)

A base material having a first main surface which is a curved surface shape or a polyhedral shape composed of a plurality of planes and a second main surface facing the first main surface,
It has a light emitting element substrate, which is installed on the side of the first main surface of the base material and mounts a plurality of light emitting elements, respectively.
The light emitting element substrate includes a thin film transistor that controls lighting of the light emitting element.
The thin film transistor includes a first thin film transistor provided on the light emitting element substrate in the central portion of the first main surface, and a second thin film transistor provided on the light emitting element substrate on the peripheral portion of the first main surface. The resistance of the first semiconductor layer included in the first thin film transistor is defined by the specific resistance, thickness, width and length of the second semiconductor layer included in the second thin film transistor. A light emitting device that is smaller than the resistance defined by the resistance, thickness, width, and length. The light emitting device according to claim 1, wherein the base material has wiring electrically connected to the light emitting element. The light emitting device according to claim 1 or 2, wherein the first main surface is curved in a convex shape. The light emitting device according to any one of claims 1 to 3, wherein the second main surface is curved in a concave shape. The light emitting device according to any one of claims 1 to 4, wherein a heat radiating member is installed on the side of the second main surface of the base material. The light emitting device according to any one of claims 1 to 5, further comprising a brightness control device that controls the brightness of the light emitting element for each light emitting element substrate. In the brightness control device, the brightness of the light emitting element substrate in the central portion of the first main surface of the base material is equal to or less than the brightness of the light emitting element substrate in the peripheral portion of the first main surface. The light emitting device according to claim 6. The plurality of the light emitting element substrates include those in the central portion and those in the peripheral portion of the first main surface.
The luminous efficiency of the first light emitting element mounted on the light emitting element substrate in the central portion of the first main surface is the second light emission mounted on the light emitting element substrate in the peripheral portion of the first main surface. The light emitting device according to any one of claims 1 to 7, which has a higher luminous efficiency than the element. The light emitting device according to any one of claims 1 to 8, wherein the plurality of light emitting element substrates have a space between adjacent light emitting element substrates. The plurality of the light emitting element substrates are such that the distance between the light emitting element substrate in the peripheral portion of the base material and the light emitting element substrate in the central portion of the base material is the distance between the light emitting element substrate in the central portion. The light emitting device according to claim 9, wherein the light emitting device is larger than the distance between the adjacent parts or larger than the distance between the adjacent parts of the light emitting element substrate in the peripheral portion. A base material having a first main surface which is a curved surface shape or a polyhedral shape composed of a plurality of planes and a second main surface facing the first main surface,
It has a light emitting element substrate, which is installed on the side of the first main surface of the base material and mounts a plurality of light emitting elements, respectively.
The light emitting element substrate includes a thin film transistor that controls lighting of the light emitting element.
The thin film transistor includes a first thin film transistor provided on the light emitting element substrate in the central portion of the first main surface, and a second thin film transistor provided on the light emitting element substrate on the peripheral portion of the first main surface. A light emitting device comprising the above, wherein the electron mobility of the first semiconductor layer included in the first thin film transistor is larger than the electron mobility of the second semiconductor layer included in the second thin film transistor.

Images