Light-emitting display device

Abstract

This light-emitting display device comprises: a plurality of light sources; a plurality of sub light-guide parts; and a main light-guide part. The light-emitting display device is configured such that: the sub light-guide parts each have an elongated shape and comprise one of the plurality of light sources at an end part; the main light-guide part comprises a light-emitting surface, a first reflection surface, and a second reflection surface; the light-emitting surface is disposed in parallel with the y-axis and the z-axis of the xyz orthogonal coordinate system; the sub light-guide parts are connected to the main light-guide part directly or with respective connection parts therebetween, in a range of different z-coordinates; a supplementary angle of the angle formed by the light-emitting surface and the first reflection surface is in the range of 30 to 50 degrees; the light-emitting surface and the second reflection surface face each other; the sub light-guide parts are connected to the main light-guide part in a region between the first reflection surface and the second reflection surface; the sub light-guide parts transmit light from the corresponding light source provided at the end part by internal reflection; and in the main light-guide part, the light received from each of the sub light-guide parts is reflected by the first reflection surface, and then reaches the light-emitting surface directly or after reflection by the second reflection surface.

Description

Light-emitting display device

[0001] The present invention relates to a light-emitting display device.

[0002] Light-emitting display devices equipped with a light source such as an LED and a light guide unit have been developed (for example, Patent Document 1 and Patent Document 2). By changing the emission time, intensity, etc. of a plurality of different types of light sources, various light emission patterns can be provided by such a light-emitting display device. Such a light-emitting display device can be suitably used as automotive interior illumination, automotive exterior signal lights, illumination for gaming machines, a light-emitting display device for indicating the operating state of electronic devices, a backlight for a capacitive touch sensor, a human machine interface, etc.

[0003] However, a light-emitting display device equipped with a light source and a light guide unit that can uniformly emit light from a planar light-emitting region has not been developed. Therefore, there is a need for a light-emitting display device equipped with a light source and a light guide unit that can uniformly emit light from a planar light-emitting region.

[0004] JP-A-2013-143252 JP-A-2019-129135

[0005] The technical problem of the present invention is to provide a light-emitting display device equipped with a light source and a light guide unit that can uniformly emit light from a planar light-emitting region.

[0006] The light-emitting display device of the present invention comprises a plurality of light sources, a plurality of sub-light guides, and a main light section, each sub-light guide having an elongated shape with one of the plurality of light sources at its end, and the main light section comprising a light-emitting surface, a first reflective surface, and a second reflective surface. The light-emitting surface is arranged parallel to the y and z axes of the xyz Cartesian coordinate system, and each sub-light guide has a connecting portion, which is connected to the main light section via or directly to the connecting portion in different z coordinate ranges. The complementary angle between the light-emitting surface and the first reflective surface is in the range of 30 to 50 degrees, the light-emitting surface and the second reflective surface face each other, and each sub-light guide is connected to the main light section in the region between the first reflective surface and the second reflective surface. Each sub-light guide transmits light from the end light source through internal reflection, and the main light guide is configured such that the light received from each sub-light guide is reflected by the first reflective surface, and then either directly or by the second reflective surface before reaching the light-emitting surface.

[0007] The light-emitting display device of the present invention is characterized in that the complementary angle between the light-emitting surface of the main light unit and the first reflective surface is in the range of 30 to 50 degrees, the light-emitting surface of the main light unit and the second reflective surface face each other, and each sub-light guide unit is connected to the main light unit in the region between the first reflective surface and the second reflective surface. With the above configuration, the light-emitting surface can be made to emit light uniformly by the light from each sub-light guide unit.

[0008] In the light-emitting display device of the first embodiment of the present invention, the ranges of two adjacent z coordinates among the ranges of multiple z coordinates to which the multiple sub-light guides are connected to the main light section partially overlap each other.

[0009] In the light-emitting display device of the second embodiment of the present invention, a plurality of linear grooves are formed on the first reflective surface, the spacing and depth of the plurality of linear grooves are constant, the angle formed by the plurality of linear grooves on the first reflective surface is in the range of 20 to 50 degrees with respect to the projection of the x-axis onto the first reflective surface, and the depth of the grooves is in the range of 0.01 millimeters to 1 millimeter.

[0010] The multiple linear grooves described above can increase the brightness of the light-emitting surface and further improve its uniformity.

[0011] A third embodiment of the present invention is a light-emitting display device of the second embodiment, wherein, in a cross section perpendicular to the direction of the plurality of linear grooves, the acute angle γ between the linear line corresponding to the side surface of the connection area between the leading light section and the auxiliary light guide section of each groove and the depth direction of the groove is in the range of 35 to 55 degrees, and the acute angle δ between the linear line corresponding to the side of the connection area between the leading light section and the auxiliary light guide section of each groove and the depth direction of the groove is in the range of 60 to 80 degrees.

[0012] The groove shape described above further improves the brightness and uniformity of the light-emitting surface.

[0013] In the fourth embodiment of the present invention, the light-emitting display device is a diffuse reflecting surface.

[0014] By making the second reflective surface a diffuse reflective surface, the uniformity of the brightness of the light-emitting surface is further improved.

[0015] In the fifth embodiment of the present invention, the light-emitting surface and the second reflective surface are parallel, or in the xy cross-section of the leading light portion, the angle between the straight line corresponding to the light-emitting surface and the straight line corresponding to the second reflective surface is 20 degrees or less.

[0016] In the sixth embodiment of the present invention, the divergence angle of half-maximum of each light source is configured to be in the range of 10 to 30 degrees.

[0017] The above configuration further improves the brightness and uniformity of the light-emitting surface.

[0018] In the fifth embodiment of the present invention, the light-emitting surface is a curved surface that is curved in the direction of the y-axis, the z-axis, or both directions from a plane parallel to the y-axis and the z-axis.

[0019] This is a plan view of an example of the present invention's light-emitting display device. This is a front view of the above example of the present invention's light-emitting display device. This is a side view of the above example of the present invention's light-emitting display device. This is a diagram showing the path of light emitted by a light source. This is a diagram showing the x and y cross-sections of the light-emitting display device. This is a diagram for explaining the connection between the auxiliary light guide and the main light section. Figure 4A is a plan view of the light-emitting display device, similar to Figure 1A. This is a diagram showing the D-D cross-section of Figure 4A. This is a diagram showing the A-A cross-section of Figure 4A. This is a diagram showing the B-B cross-section of Figure 4A. This is a diagram showing the C-C cross-section of Figure 4A. This is a diagram showing the C'-C' cross-section of Figure 4A. This is a diagram showing the A-A cross-section of Figure 4A. This is a diagram showing the B-B cross-section of Figure 4A. This is a diagram showing the C-C cross-section of Figure 4A. This is a perspective view showing the first reflective surface R1 of the auxiliary light guide and the main light section. This is a diagram showing the first reflective surface R1. This is a diagram showing a cross-section perpendicular to the direction of the multiple linear grooves of the first reflective surface R1. This is a diagram for explaining the cross-section PL of Figure 9A. This figure shows the xy cross-section of the first reflective surface R1 of the main light unit and the surrounding portion. This is a view of the secondary light guide unit and the main light unit from diagonally above. This figure shows the rectangular region on the light-emitting surface E where light is emitted after passing through the secondary light guide unit 401. This is a plan view of the secondary light guide unit 403, which has the largest z-coordinate range for the portion connected to the main light unit. This figure shows the FF cross-section of Figure 13A. This is a plan view of the light-emitting display device similar to Figure 1A. This is a conceptual diagram showing the luminance distributions I1, I2, and I3 in the z-axis direction on the light-emitting surface E due to light passing through the secondary light guide units 401, 402, and 403. This is a perspective view of a light-emitting display device including a light source equipped with a divergence angle adjustment unit. This is a cross-sectional view of the light source equipped with a divergence angle adjustment unit. This is a plan view of a secondary light guide unit equipped with a light source equipped with a divergence angle adjustment unit. This is a perspective view of a light-emitting display device in which multiple light sources are arranged at large intervals in the z-axis direction. This is a perspective view of a light-emitting display device in which three light sources are arranged near both ends of the z-axis side of the light-emitting surface.

[0020] Figure 1A is a plan view of an example of a light-emitting display device according to the present invention.

[0021] Figure 1B is a front view of the above example of a light-emitting display device according to the present invention.

[0022] Figure 1C is a side view of the above example of a light-emitting display device according to the present invention.

[0023] The x, y, and z coordinate system is defined such that the plane shown in Figure 1A is perpendicular to the y-axis, the plane shown in Figure 1B is perpendicular to the x-axis, and the plane shown in Figure 1C is perpendicular to the z-axis. The origin of the x, y, and z coordinate system will be explained later.

[0024] The light-emitting display device of the present invention is composed of a plurality of light sources, a plurality of sub-light guides, and a main light section 300. Each of the plurality of light sources is provided at one end of the plurality of sub-light guides. In the example shown in the figure, the plurality of sub-light guides are represented by 401, 402, and 403, and the light sources provided at their respective ends are represented by 101, 102, and 103. As shown in Figure 1C, the main light section 300 includes a first reflective surface R1, a second reflective surface R2, and a light-emitting surface E perpendicular to the x-axis direction.

[0025] The light-emitting surface E is parallel to the y-axis and z-axis. In this example, the light-emitting surface is a rectangular plane with sides in the y-axis and z-axis directions. The length of the side in the y-axis direction is 300 millimeters, and the length of the side in the z-axis direction is 50 millimeters. Generally, the shape of the light-emitting surface is not limited to a rectangle. It may also be a curved surface, as will be explained later. The origin of the xyz coordinate system is one of the vertices of the rectangle formed by the sides in the y-axis direction and the z-axis direction of the light-emitting surface E. The coordinates of the y-axis and z-axis are determined so that the coordinates of the sides in the y-axis and z-axis directions of the rectangle are positive. The coordinate of the x-axis is determined so that the coordinates of the multiple light sources are positive. In this example, the origin is the upper left vertex of Figure 1B.

[0026] The light sources 101, 102, and 103 may be light-emitting diodes (LEDs). The materials for the main light section 300 and the sub-light guide sections 401, 402, and 403 are preferably highly transparent thermoplastic resins such as polymethyl acrylate, polycarbonate, and polyolefin resins. The main light section 300 and the sub-light guide sections 401, 402, and 403 can be easily manufactured by injection molding.

[0027] Figure 2 shows the path of light emitted by the light source 101. Figure 2 is a plan view of the light-emitting display device similar to Figure 1A. The secondary light guide is elongated, such as a rod. The light emitted by the light source 101 travels through the secondary light guide 401, repeatedly reflecting as it goes. A portion of the light traveling through the secondary light guide 401 reaches the main light source 300 via the connecting portion 411.

[0028] Figure 3 shows an xy cross-section of the light-emitting display device. Figure 3 shows only the sub-light guide 401 of several sub-light guides. The main light section 300 comprises a first reflective surface R1, a second reflective surface R2, and a light-emitting surface E. The light-emitting surface E is adjacent to the first reflective surface R1 and faces the second reflective surface R2. The sub-light guide 401 or its connection portion 411 is connected to the main light section 300 in the region between the first reflective surface R1 and the second reflective surface R2. The supplementary angle α of the angle between the first reflective surface R1 and the light-emitting surface E is in the range of 30 to 50 degrees. Light that reaches the main light section 300 via the sub-light guide 401 is reflected by the first reflective surface R1 and then emitted from the light-emitting surface E either directly or after being reflected by the second reflective surface R2. The second reflective surface R2 and the light-emitting surface E are parallel or the acute angle α' between them is 20 degrees or less. As will be explained later, multiple grooves or textures may be formed on the reflective surface. In that case, the angle between the two surfaces is determined by a virtual plane defined by the average depth of the grooves or textures.

[0029] The main light source and the secondary light guide will be described in detail below.

[0030] Figure 4A is a diagram illustrating the connection between the sub-light guide and the main light source. Figure 4A is a plan view of the light-emitting display device, similar to Figure 1A.

[0031] Figure 4B shows the section D-D in Figure 4A. The section D-D is perpendicular to the x-axis.

[0032] Figure 5A shows the A-A cross-section of Figure 4A. The A-A cross-section is perpendicular to the z-axis.

[0033] Figure 5B shows the B-B cross-section of Figure 4A. The B-B cross-section is perpendicular to the z-axis.

[0034] Figure 5C is a diagram showing the C-C cross-section of Figure 4A. The C-C cross-section is a cross-section perpendicular to the z-axis.

[0035] Figure 5D is a diagram showing the C'-C' cross-section of Figure 4A. The C'-C' cross-section is a cross-section perpendicular to the z-axis.

[0036] Figure 6A is a diagram showing the A-A cross-section of Figure 4A.

[0037] Figure 6B is a diagram showing the B-B cross-section of Figure 4A.

[0038] Figure 6C is a diagram showing the C-C cross-section of Figure 4A.

[0039] Figure 6D is a diagram showing the C'-C' cross-section of Figure 4A.

[0040] Figures 5A - 5D are diagrams for explaining the positional relationship between the main light guide portion 300 and the sub-light guide portions 401 and 402 connected thereto. Figures 6A - 6D are diagrams for explaining the positional relationship between the main light guide portion 300 and all the sub-light guide portions.

[0041] Figure 4B shows the interface between the connecting portion 411 of the sub-light guide portion 401 and the main light guide portion 300 or the interface between the sub-light guide portion 401 and the main light guide portion 300. The D-D cross-section shown in Figure 4B is a yz cross-section perpendicular to the x-axis as described above. The interface extends substantially along the z-axis direction. The size of the interface in the y-axis direction increases as the z-coordinate increases, that is, as it moves away from the light source 101, in a region that is approximately 60 percent of the length in the z-axis direction.

[0042] In the A-A cross-section shown in Figure 5A and the B-B cross-section shown in Figure 5B, the sub-light guide portion 401 is connected to the main light guide portion 300 via the connecting portion 411.

[0043] In the C-C cross-section shown in Figure 5C, the sub-light guide portion 401 is directly connected to the main light guide portion 300 without passing through the connecting portion 411.

[0044] In the C'-C' cross-section shown in Figures 5D and 6D, the sub-light guide portion 401 is directly connected to the main light guide portion 300 without passing through the connecting portion 411, and the sub-light guide portion 402 is connected to the main light guide portion 300 via the sub-light guide portion 401.

[0045] Each sub-light guide part is connected to the main light guide part 300 within different ranges of the z coordinate, and among the plurality of ranges to which the plurality of sub-light guide parts are connected, two adjacent ranges in the z-axis direction partially overlap each other. In FIGS. 5A - 5D, the boundary surface with the main light guide part 300 or the boundary surface between the sub-light guide part 401 and the main light guide part 300 is shown by a broken line.

[0046] FIG. 7 is a perspective view showing the first reflection surface R1 of the sub-light guide part and the main light guide part 300. In the region shown in FIG. 7, the sub-light guide part 401 is connected to the main light guide part 300 via the connecting part 411 or directly. As shown by the arrow in FIG. 7, the light rays from the sub-light guide part 401 reach the first reflection surface R1 and are reflected.

[0047] FIG. 8 is a view showing the first reflection surface R1. A plurality of linear grooves are formed on the surface of the first reflection surface, and the period and depth of the plurality of linear grooves are constant. On the first reflection surface R1, with respect to the projection of the y-axis onto the first reflection surface R1, the counterclockwise angle β formed by the plurality of linear grooves is in the range of 20 degrees to 50 degrees. In this example, as shown in FIG. 2, the light travels from left to right along the horizontally arranged z-axis within the sub-light guide tube. In other embodiments, when the light travels from right to left along the horizontally arranged z-axis within the sub-light guide tube, on the first reflection surface R1, with respect to the projection of the y-axis onto the first reflection surface R1, the clockwise angle formed by the plurality of linear grooves is in the range of 20 degrees to 50 degrees.

[0048] FIG. 9A is a view showing a cross-section perpendicular to the direction of the plurality of linear grooves of the first reflection surface R1.

[0049] FIG. 9B is a view for explaining the cross-section PL in FIG. 9A.

[0050] Multiple linear grooves are formed from a first set of faces that are parallel to each other and a second set of faces that are not parallel to each other. In Figure 9A, the two sets of faces are shown by two sets of straight lines. The intersections of the two sets of straight lines correspond to the ridges and valleys of the grooves. In Figure 9A, with respect to the ridge of the groove, the acute angle γ between the straight line corresponding to the face opposite the second reflective surface and the groove depth direction is in the range of 35 to 55 degrees. With respect to the ridge of the groove, the acute angle δ between the straight line corresponding to the face on the side of the second reflective surface and the groove depth direction is in the range of 70 to 80 degrees. The groove depth is preferably in the range of 0.05 millimeters to 0.5 millimeters, but may be in the range of 0.01 millimeters to 1 millimeter.

[0051] Figure 10 shows an xy cross-section of the first reflective surface R1 and its surrounding area of ​​the leading light unit 300. The light rays reflected by the first reflective surface R1 are further reflected by the second reflective surface R2 and emitted from the light-emitting surface E.

[0052] Multiple linear grooves in the z-axis direction may be formed on the surface of the second reflective surface R2. The period and depth of the grooves may be adjusted according to the y-coordinate so that the brightness in the y-axis direction of the light-emitting surface E is uniform. Specifically, the period of the grooves may be decreased or the depth of the grooves may be increased, or both, as the distance in the y-axis direction from the first reflective surface R1 increases. Generally, it is preferable that the second reflective surface R2 be a diffuse reflective surface that produces diffuse reflection (non-specular reflection) rather than specular reflection. Therefore, a so-called textured surface consisting of surface irregularities may be formed. The average period of the multiple linear grooves, textures, and other irregularities is in the range of 0.05 to 1 millimeter, and the average depth of the irregularities is in the range of 0.01 to 0.2 millimeters.

[0053] Figure 11 is a view of the secondary light guide and the main light guide from an oblique angle above. Most of the light rays from the secondary light guide are reflected by the first reflective surface R1 as shown in a, and then reach the second reflective surface R2. On the other hand, some of the light rays are not reflected by the first reflective surface R1 as shown in b, and reach the second reflective surface R2 directly. If the reflective surface R2 is flat, the light rays shown in b may cause unevenness in brightness on the light-emitting surface E after being reflected by the second reflective surface R2. However, unevenness in brightness can be prevented by shaping the second reflective surface R2 as described above.

[0054] Figure 12 shows a rectangular region on the light-emitting surface E where light is emitted via the sub-light guide 401. The sub-light guide 401 is connected to the main light section 300 within the range of the z coordinates corresponding to the above region.

[0055] Figure 13A is a plan view of the sub-light guide unit 403, which has the largest z-coordinate range in the portion connected to the main light unit 300.

[0056] Figure 13B shows the FF cross-section of Figure 13A. In the region where the z-coordinate of the sub-light guide 403 is relatively large, the outer surface opposite to the first reflective surface R1 is formed as a plane 403R. Reflection at the plane 403R increases the amount of light reaching the first reflective surface R1.

[0057] Figure 14A is a plan view of the light-emitting display device similar to Figure 1A. In Figure 14A, the regions where the sub-light guides 401, 402, and 403 are connected to the main light section 300 are indicated by A1, A2, and A3, respectively. Two adjacent regions A1 and A2, and A2 and A3, within the connection range of the sub-light guides, in the z-axis direction, partially overlap each other. Figure 14B is a conceptual diagram showing the z-axis direction luminance distributions I1, I2, and I3 on ​​the light-emitting surface E due to light passing through the sub-light guides 401, 402, and 403. The luminance distributions I1, I2, and I3 correspond to regions A1, A2, and A3, respectively. Therefore, the luminance distributions I1 and I2, and the luminance distributions I2 and I3, partially overlap.

[0058] In the light-emitting display device of the present invention, as shown in Figure 4B, the luminance distribution in the z-axis direction on the light-emitting surface E, as shown in Figure 14B, can be adjusted by changing the size in the y-axis direction of the yz cross-section of the interface between the connection portion of each sub-light guide and the main light section, or the interface between each sub-light guide and the main light section, according to the z-coordinate. Furthermore, as shown in Figure 13B, the luminance distribution in the z-axis direction can also be adjusted by making the outer surface opposite to the first reflective surface R1 of the sub-light guide, which has the largest z-coordinate at the portion connected to the main light section, a flat surface.

[0059] Furthermore, in the light-emitting display device of the present invention, with respect to the first reflective surface, by setting angles α shown in Figure 3, β shown in Figure 8, γ shown in Figure 9A, and δ shown in Figure 9A to appropriate values, and appropriately determining the shape of the second reflective surface, the brightness on the light-emitting surface E can be increased and the brightness in the y-axis direction can be made uniform. In fact, simulations show that the average brightness on the light-emitting surface E when the grooves on the first reflective surface are provided is approximately four times the average brightness on the light-emitting surface E when the grooves on the first reflective surface are not provided.

[0060] Other embodiments will be described.

[0061] Figure 15 is a perspective view of a light-emitting display device including a light source equipped with a divergence angle adjustment unit.

[0062] Figure 16 is a cross-sectional view of a light source equipped with a divergence angle adjustment unit. The divergence angle adjustment unit 101A consists of a lens and a reflective surface. The divergence angle of an LED light source without a divergence angle adjustment unit is approximately 70 degrees at half maximum. It is preferable to set the divergence angle at half maximum to a range of 10 to 30 degrees using the divergence angle adjustment unit.

[0063] Figure 17 is a plan view of a sub-light guide unit equipped with a light source that has a divergence angle adjustment unit.

[0064] The light-emitting display device of this embodiment has the following advantages by reducing the divergence angle. In the light-emitting display device, a portion of the light that reaches the first reflective surface from the sub-light guide is not reflected by the first reflective surface but passes through it and is emitted to the outside. By reducing the divergence angle of the light source, the proportion of light emitted to the outside is reduced, improving utilization efficiency and allowing the brightness of the light-emitting surface to be increased. Also, as shown by ray b in Figure 11, the proportion of light that is reflected by the first reflective surface and then reaches the light-emitting surface directly without being reflected by the second reflective surface is reduced, making it easier to achieve a uniform brightness distribution on the light-emitting surface. On the other hand, since the light-emitting display device of this embodiment is equipped with a divergence angle adjustment unit, the diameter of the cross-section of the sub-light guide unit becomes larger. Therefore, the width of the main light unit in the x-axis direction also needs to be increased.

[0065] Figure 18 is a perspective view of a light-emitting display device in which multiple light sources are arranged at large intervals in the z-axis direction. In the light-emitting display device shown in Figure 1A, the multiple light sources are arranged in close proximity to each other. In this case, since the light sources such as LEDs can be installed on the same substrate, it is advantageous from a cost standpoint. On the other hand, the lengths of the sub-light guides 402 and 403 become large. In the light-emitting display device shown in Figure 18, the sub-light guides 402 and 403 can be shortened, making it easier to manufacture by injection molding. In addition, the size of the light-emitting display device in the x-axis direction can be reduced.

[0066] Figure 19 is a perspective view of a light-emitting display device in which two sets of three light sources (401, 402, 403) and (404, 405, 406) are arranged near both ends of the z-axis side of the light-emitting surface. With the above configuration, the number of light sources can be increased without increasing the size of the light-emitting display device in the x-axis direction.

[0067] In another embodiment, a diffuse reflective surface such as a textured surface may be partially formed on the second reflective surface, and the other part may be made into a mirror surface, so that a pattern is generated on the light-emitting surface by the partially formed diffuse reflective surface.

[0068] In yet another embodiment, the light-emitting surface may be a curved surface that is curved in the direction of the y-axis, the z-axis, or both directions from a plane parallel to the y-axis and the z-axis.

[0069] As a method of using the light-emitting display device of the present invention, another light-emitting display device can be installed adjacent to the second reflective surface, and the light from both devices can be displayed on the light-emitting surface.

[0070] If no other light-emitting display device is installed adjacent to the second reflective surface, a diffuse reflective surface or a specular reflective surface can be installed adjacent to the second reflective surface to reflect the light emitted after passing through the second reflective surface and increase the brightness of the light-emitting surface.

Claims

1. A light-emitting display device comprising a plurality of light sources, a plurality of sub-light guides, and a main light section, wherein each sub-light guide has an elongated shape with one of the plurality of light sources at its end, the main light section comprises a light-emitting surface, a first reflective surface, and a second reflective surface, the light-emitting surface is arranged parallel to the y and z axes of an xyz Cartesian coordinate system, each sub-light guide is connected to the main light section in different z coordinate ranges, the complementary angle of the angle between the light-emitting surface and the first reflective surface is in the range of 30 to 50 degrees, the light-emitting surface and the second reflective surface face each other, each sub-light guide is connected to the main light section in the region between the first reflective surface and the second reflective surface, each sub-light guide transmits light from the light source at its end by internal reflection, and the main light section is configured such that light received from each sub-light guide reaches the light-emitting surface either directly or after being reflected by the second reflective surface after being reflected by the first reflective surface.

2. The light-emitting display device according to claim 1, wherein the ranges of two adjacent z coordinates among the ranges of multiple z coordinates to which the multiple sub-light guides are connected to the main light section partially overlap each other.

3. The light-emitting display device according to claim 1, wherein a plurality of linear grooves are formed on the first reflective surface, the spacing and depth of the plurality of linear grooves are constant, the angle formed by the plurality of linear grooves on the first reflective surface is in the range of 20 to 50 degrees with respect to the projection of the y-axis onto the first reflective surface, and the depth of the grooves is in the range of 0.01 millimeters to 1 millimeter.

4. The light-emitting display device according to claim 3, wherein, in a cross section perpendicular to the direction of the plurality of linear grooves, the acute angle γ formed between the linear line corresponding to the surface opposite to the second reflective surface and the depth direction of the groove, with respect to the ridge of each groove, is in the range of 35 to 55 degrees, and the acute angle δ formed between the linear line corresponding to the side surface of the second reflective surface and the depth direction of the groove, with respect to the ridge of each groove, is in the range of 60 to 80 degrees.

5. The light-emitting display device according to claim 1, wherein the second reflective surface is a diffuse reflective surface.

6. The light-emitting device according to claim 1, wherein the light-emitting surface and the second reflective surface are parallel, or in the xy cross-section of the leading light portion, the angle between the straight line corresponding to the light-emitting surface and the straight line corresponding to the second reflective surface is 20 degrees or less.

7. The light-emitting device according to claim 1, configured to set the divergence angle of half-maximum of each light source to a range of 10 to 30 degrees.

8. The light-emitting device according to claim 1, wherein the light-emitting surface is a curved surface that is curved in the direction of the y-axis, the z-axis, or both directions from a plane parallel to the y-axis and the z-axis.

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