Partitioning member and planar light source

Abstract

A planar light source, in a planar light source having a separating member, suppresses thermal shrinkage of the separating member. The planar light source includes: a substrate; a plurality of light sources disposed on the substrate; and at least one separating member disposed on the substrate. The separating member has: a plurality of first wall portions having first ridges extending in a first direction; a plurality of second wall portions having second ridges extending in a second direction intersecting the first direction; and a separating region including two opposing first wall portions and two opposing second wall portions, and being surrounded by the first ridges and the second ridges when viewed from above. A plurality of separating regions are disposed in the first and second directions, and at least one first cutout is provided on at least one of the first ridges. The light sources are respectively disposed within the separating regions.

Description

[Technical Field]

[0001] This invention relates to a separating component and a planar light source. [Previous Technology]

[0002] A known lighting device includes a substrate with a plurality of light-emitting elements arranged thereon and a reflective member disposed on the substrate. In this lighting device, light-emitting elements are disposed in each opening of the reflective member. In this lighting device, the reflective member undergoes thermal shrinkage under high temperature conditions, sometimes resulting in uneven brightness. Therefore, countermeasures are implemented to reduce the impact of thermal shrinkage of the reflective member (for example, see Patent Document 1). <Prior Art Documents> <Patent Documents>

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-185921 [Summary of the Invention]

[0004] <The Problem the Invention Intends to Solve>

[0005] The object of the present invention is to suppress thermal shrinkage of the separating member in a planar light source having a separating member. Furthermore, the object of the present invention is to provide a separating member used in such a planar light source, and a liquid crystal display device using such a planar light source. <Means for Solving the Problem>

[0006] One embodiment of the planar light source of the present invention includes: a substrate; a plurality of light sources disposed on the substrate; and at least one partition member disposed on the substrate. The partition member has: a plurality of first wall portions having first ridges extending in a first direction; a plurality of second wall portions having second ridges extending in a second direction intersecting the first direction; and partition regions including two opposing first wall portions and two opposing second wall portions, and being surrounded by the first ridges and the second ridges when viewed from above. A plurality of partition regions are disposed in the first direction and the second direction, and at least one first cutout is provided on at least one of the first ridges. The light sources are respectively disposed in the partition regions. <Effects of the Invention>

[0007] According to one embodiment of the present invention, thermal shrinkage of the separating member can be suppressed in a planar light source having a separating member. Furthermore, a separating member used in the planar light source and a liquid crystal display device using the planar light source are provided.

Implementation Method

[0009] Hereinafter, the embodiments for carrying out the invention will be described with reference to the drawings. It should be noted that in the following description, terms indicating specific directions and positions (e.g., "up," "down," and other terms including these terms) are used as needed. However, the use of these terms is to facilitate understanding of the invention with reference to the drawings, and the technical scope of the invention is not limited by the meaning of these terms. In addition, the parts represented by the same symbols in the plurality of drawings represent the same or equivalent parts or components.

[0010] Furthermore, the embodiments shown below exemplify planar light sources, etc., used to embody the technical concept of the present invention, and do not limit the present invention to the following content. Also, unless there is a specific description, the dimensions, materials, shapes, and relative arrangements of the constituent components described below are not intended to limit the scope of the present invention, but are merely examples. Furthermore, the content described in one embodiment can also be applied to other embodiments and variations. Additionally, the size, position, and other aspects of the components shown in the drawings are sometimes exaggerated for clarity. Moreover, to avoid making the drawings overly complex, schematic diagrams with some elements omitted are sometimes used, or end views showing only the cut surfaces are used as cross-sectional views. <First Embodiment>

[0011] In the first embodiment, the separating member will be described first, and then a planar light source in which the separating member and the light source are disposed on the substrate will be described. [Separating Member 1]

[0012] Figure 1 is a top view illustrating the partition component 1. Figure 2 is a cross-sectional view along line II-II of Figure 1.

[0013] As shown in Figures 1 and 2, the partition member 1 has a plurality of first wall portions 10, a plurality of second wall portions 20, and a plurality of partition regions 30. The plurality of first wall portions 10 are arranged parallel to each other, for example. Similarly, the plurality of second wall portions 20 are arranged parallel to each other, for example. The partition member 1 may have a plurality of bottom portions 40 as needed. The following description will take the case where the partition member 1 has a plurality of bottom portions 40 as an example.

[0014] The first wall portion 10 has a first ridge 11 extending in a first direction, a first sidewall 12, and a second sidewall 13. The first sidewall 12 and the second sidewall 13 are arranged apart from the first ridge 11 when viewed from above. The upper end of the first sidewall 12 is continuous with the upper end of the second sidewall 13. There is a space between the first sidewall 12 and the second sidewall 13.

[0015] The first ridge line 11 is the line connecting the highest point of the first wall portion 10. In a cross-section cut in a direction orthogonal to the first ridge line 11, the area near the first ridge line 11 can be either pointed or rounded. Alternatively, the first ridge line 11 can be a flat portion extending linearly with an extremely narrow width. This flat portion is not the wide width used in threaded fastening, but rather a width narrower than the threaded hole. The width of this flat portion is, for example, 1 mm or less. Furthermore, the first ridge line 11 does not have a widened portion used in threaded fastening; it is essentially a constant width.

[0016] The second wall portion 20 has a second ridge 21 extending in a second direction intersecting the first direction, a third side wall 22, and a fourth side wall 23. The third side wall 22 and the fourth side wall 23 are arranged separated by the second ridge 21 when viewed from above. The upper end of the third side wall 22 is continuous with the upper end of the fourth side wall 23. There is a space between the third side wall 22 and the fourth side wall 23.

[0017] The second ridge line 21 is the line connecting the highest point of the second wall portion 20. In a cross-section cut in a direction orthogonal to the second ridge line 21, the area near the second ridge line 21 can be either pointed or rounded. Alternatively, the second ridge line 21 can be a flat portion extending linearly with an extremely narrow width. This flat portion is not the wide width used in threaded fastening, but rather a width narrower than the threaded hole. The width of this flat portion is, for example, 1 mm or less. Furthermore, the second ridge line 21 does not have a widened portion used in threaded fastening; it is essentially a constant width.

[0018] In Figure 1, the X and Y directions, which are orthogonal to each other, are defined, and the direction perpendicular to the X and Y directions is set as the Z direction. In the partition member 1, either of the directions in which the two edges extend can be set as the first direction. Here, the X direction of the orthogonal X and Y directions in Figure 1 is set as the first direction X, and the Y direction is set as the second direction Y for the following explanation. However, in the partition member 1, the first direction and the second direction may not be orthogonal. It should be noted that in the following explanation, the -X direction of the object part is sometimes referred to as the X-side, the +X direction as the X+ side, the -Y direction as the Y-side, and the +Y direction as the Y+ side.

[0019] The dividing region 30, when viewed from above, is the area surrounded by the first edge 11 and the second edge 21. A plurality of dividing regions 30 are arranged in the first and second directions. In the example of Figure 1, the plurality of dividing regions 30 are arranged in a row-column configuration, with the first direction X set as the row direction and the second direction Y set as the column direction. The number of dividing regions 30 arranged in each row direction can be the same or different. Similarly, the number of dividing regions 30 arranged in each column direction can be the same or different. In the example of Figure 1, when viewed from above, the plurality of rectangular dividing regions 30 are arranged in a 4-row, 8-column configuration.

[0020] Each partition region 30 includes two opposing first wall portions 10, two opposing second wall portions 20, and a bottom 40. The bottom 40 is, for example, rectangular when viewed from above. In each partition region 30, the two opposing first wall portions 10 are a first sidewall 12 located at the outer edge of the Y-side of the bottom 40, and a second sidewall 13 located at the outer edge of the Y+side of the bottom 40. Additionally, in each partition region 30, the two opposing second wall portions 20 are a third sidewall 22 located at the outer edge of the X-side of the bottom 40, and a fourth sidewall 23 located at the outer edge of the X+side of the bottom 40.

[0021] The outer edge of the bottom 40 is connected to the lower ends of the first sidewall 12, the second sidewall 13, the third sidewall 22, and the fourth sidewall 23. That is, the first sidewall 12, the second sidewall 13, the third sidewall 22, and the fourth sidewall 23 are configured as a frame surrounding the bottom 40 when viewed from above. The first sidewall 12, the second sidewall 13, the third sidewall 22, and the fourth sidewall 23 are inclined relative to the bottom 40. In each partition region 30, the distance in the second direction Y between the regions enclosed by the opposing first sidewall 12 and the second sidewall 13 is narrower towards the bottom 40 and wider towards the top. In addition, in each partition region 30, the distance in the first direction X between the regions enclosed by the opposing third sidewall 22 and the fourth sidewall 23 is narrower towards the bottom 40 and wider towards the top.

[0022] An opening 40x is provided at the bottom 40. When the separating member 1 is used as a planar light source, the opening 40x is an area where the light source can be arranged. The opening 40x is, for example, located at the center of the bottom 40, and does not reach the lower ends of the first sidewall 12, the second sidewall 13, the third sidewall 22, and the fourth sidewall 23. When viewed from above, the area of ​​the opening 40x is smaller than the area of ​​the bottom 40. The opening 40x is, for example, circular when viewed from above.

[0023] In a longitudinal section cut through the center of the bottom 40 and parallel to the second direction Y, the first wall portion 10, which preferably includes the first ridge 11, the first sidewall 12, and the second sidewall 13, is preferably V-shaped with a downward opening. Furthermore, in a longitudinal section cut through the center of the bottom 40 and parallel to the first direction X (for example, FIG. 2), the second wall portion 20, which preferably includes the second ridge 21, the third sidewall 22, and the fourth sidewall 23, is preferably V-shaped with a downward opening.

[0024] It should be noted that the first wall portion 10 located on the outer edge of the Y-side of the entire partition member 1 may not have a second sidewall 13. In this case, the first ridge line 11 on the outer edge of the Y-side of the entire partition member 1 is the upper end of the first sidewall 12. A second cutout 52 may or may not be provided on the second wall portion 20 located on the outer edge of the Y-side of the entire partition member 1. Furthermore, the first wall portion 10 located on the outer edge of the Y+side of the entire partition member 1 may not have a first sidewall 12. In this case, the first ridge line 11 on the outer edge of the Y+side of the entire partition member 1 is the upper end of the second sidewall 13. A second cutout 52 may or may not be provided on the second wall portion 20 located on the outer edge of the Y+side of the entire partition member 1.

[0025] Furthermore, the second wall portion 20 located on the outer edge of the X-side of the entire partition member 1 may not have a fourth sidewall 23. In this case, the second ridge line 21 on the outer edge of the X-side of the entire partition member 1 is the upper end of the third sidewall 22. A first cutout 51 may or may not be provided on the first wall portion 10 located on the outer edge of the X-side of the entire partition member 1. Additionally, the second wall portion 20 located on the outer edge of the X+ side of the entire partition member 1 may not have a third sidewall 22. In this case, the second ridge line 21 on the outer edge of the X+ side of the entire partition member 1 is the upper end of the fourth sidewall 23. A first cutout 51 may or may not be provided on the first wall portion 10 located on the outer edge of the X+ side of the entire partition member 1.

[0026] FIG3 is a partial top view of region A of FIG1. ​​The partition member 1 has a first cut 51 provided on the first ridge 11 and a second cut 52 provided on the second ridge 21. In FIG3, a continuous cut 50 of the first cut 51 and the second cut 52 is shown as an example. In the partition member 1 and the partition member 1A described later, the first cut 51 and the second cut 52 are sometimes described using the continuous cut 50. The first cut 51 is, for example, a straight line extending in the first direction X, and the second cut 52 is, for example, a straight line extending in the second direction Y. The lengths of the first cut 51 and the second cut 52 may be the same or different.

[0027] Figure 4 is a cross-sectional view along IV-IV of Figure 3. As shown in Figure 4, the continuous cut 50 may penetrate the first wall portion 10 or the second wall portion 20. Figure 5 is a cross-sectional view (1) showing another example of the continuous cut. Figure 6 is a cross-sectional view (2) showing another example of the continuous cut. Figures 5 and 6 show cross-sections corresponding to those in Figure 4. As shown in Figures 5 and 6, the continuous cut 50 may not penetrate the first wall portion 10 or the second wall portion 20.

[0028] That is, the first cut 51 may penetrate the first wall portion 10 or may not penetrate the first wall portion 10. For example, the first cut 51 may be a bottomed recess. When the first cut 51 does not penetrate the first wall portion 10, it is preferable that the depth of the first cut 51 is more than half the thickness of the first wall portion 10. When the first cut 51 does not penetrate the first wall portion 10, the first cut 51 may be disposed on the first ridge 11 or on the lower surface of the first wall portion 10 whose position is directly below the first ridge 11. When the separating member 1 is used in the planar light source described later, if the first cut 51 is disposed on the lower surface of the first wall portion 10, the optical effect of uneven brightness can be suppressed.

[0029] Furthermore, the second cutout 52 may penetrate the second wall portion 20 or may not penetrate it. For example, the second cutout 52 may be a bottomed recess. When the second cutout 52 does not penetrate the second wall portion 20, it is preferable that the depth of the second cutout 52 is more than half the thickness of the second wall portion 20. When the second cutout 52 does not penetrate the second wall portion 20, the second cutout 52 may be disposed on the second ridge 21 or on the lower surface of the second wall portion 20 whose position is directly below the second ridge 21. When the separator 1 is used in the planar light source described later, if the second cutout 52 is disposed on the lower surface of the second wall portion 20, the optical effect of uneven brightness can be suppressed.

[0030] When viewed from above, the continuous cut portion 50 is cross-shaped. For example, the first cut portion 51 passes through the midpoint of the second cut portion 52, and the second cut portion 52 passes through the midpoint of the first cut portion 51. In the continuous cut portion 50, the intersection point of the first cut portion 51 and the second cut portion 52 coincides with intersection point I. At least one continuous cut portion 50 is required. In the example of Figure 3, continuous cut portions 50 are arranged at all intersection points I. It should be noted that, when viewed from above, the shape of the continuous cut portion 50 at intersection point I is not limited to a cross shape, but can also be L-shaped, I-shaped, T-shaped, etc.

[0031] The first cut portion 51 and the second cut portion 52, disposed at an intersection I, are disposed away from other intersections I adjacent to the intersection I. When adjacent intersections I also have continuous cut portions 50, the adjacent continuous cut portions 50 are separated and do not contact each other. The length of each of the first cut portion 51 and the second cut portion 52 constituting the continuous cut portion 50 is, for example, shorter than the length of one side of the dividing region 30. The length of each of the first cut portion 51 and the second cut portion 52 can, for example, be set to one-third the length of one side of the dividing region 30.

[0032] It should be noted that in FIG3, the continuous cut portion 50 is depicted with exaggeratedly thick lines for convenience in order to clearly indicate its position. However, in reality, the first cut portion 51 and the second cut portion 52 constituting the continuous cut portion 50 are formed, for example, with a width of about several hundred μm by preparing an intermediate body of a separating member in which the first cut portion 51 and the second cut portion 52 are not provided on the first ridge line 11 and the second ridge line 21, and forming the cut using a cutting tool such as a knife.

[0033] Furthermore, the separating member 1 can be formed by injection molding or the like. When forming by injection molding or the like, the mold is arranged in the portion corresponding to the first cut portion 51 and the second cut portion 52, so that the part is not formed in the portion corresponding to the first cut portion 51 and the second cut portion 52. In this way, the cut portion can be included even for parts that do not need to be obtained through the "cutting" process.

[0034] Alternatively, the first cut portion 51 and the second cut portion 52 can also be formed, for example, by preparing a dividing member intermediate body without the first cut portion 51 and the second cut portion 52 provided on the first ridge line 11 and the second ridge line 21, and using a die-cutting process. Specifically, for example, the first cut portion 51 and the second cut portion 52 can be formed on the dividing member intermediate body by setting a die on the lower surface side of the dividing member intermediate body and using a backing plate to stamp from the upper surface side of the dividing member intermediate body. This method is preferable because it is less likely to produce burrs when forming the first cut portion 51 and the second cut portion 52. In this case, the first cut portion 51 and the second cut portion 52 can be formed in one punching operation on the entire dividing member intermediate body, and the punching can be performed in multiple operations or one by one.

[0035] At least a portion of the first sidewall 12 and the second sidewall 13 are connected across the first cutout 51. Additionally, at least a portion of the third sidewall 22 and the fourth sidewall 23 are connected across the second cutout 52. Thus, with at least a portion of the first cutout 51 and / or the second cutout 52 connected, the separating member 1 becomes light-reflective, and when using a planar light source (described later), it is possible to suppress light directly incident from the light source onto the first cutout 51 and / or the second cutout 52, as well as light returning from the optical sheet, from entering the first cutout 51 and / or the second cutout 52. This suppresses the reduction in the amount of light extracted from the planar light source.

[0036] The separating member 1 can be disposed on the substrate and bonded to the substrate to form a planar light source. When the separating member 1 is light reflective, the first sidewall 12 and the second sidewall 13 of the first wall portion 10, the third sidewall 22 and the fourth sidewall 23 of the second wall portion 20, and the bottom 40 function as reflective members for reflecting light from the light source. That is, the separating member 1 can be used as a reflector of the planar light source.

[0037] It should be noted that "disposed on the substrate" refers to both the case where the partition member or the like is directly disposed on the upper surface of the substrate and the case where it is indirectly disposed through the cover member or the like described later. In addition, "bonded to the substrate" refers to both the case where the partition member or the like is directly bonded to the upper surface of the substrate and the case where it is indirectly bonded to the substrate through the cover member or the like described later.

[0038] When the partition member 1 is disposed on the substrate and the light source is disposed in a planar light source exposed on the substrate within each opening 40x, if a heat load is applied to the partition member 1 during storage in a high-temperature environment or during the operation of the light source, shrinkage may sometimes occur in the partition member 1. It should be noted that if the partition member 1 is stored in a high-temperature environment, there is a possibility that the individual partition member 1 may also experience thermal shrinkage.

[0039] For example, in the partition member 1X of the comparative example shown in FIG7, it is set to have no cutouts at all. If a heat load is applied to the partition member 1X, the partition member 1X will shrink toward the center as indicated by the arrow. The larger the size of the partition member 1X is when viewed from above, the greater the shrinkage of the partition member 1X. If the partition member 1X shrinks due to the heat load, the distance from the light source to the first sidewall 12, the second sidewall 13, the third sidewall 22, and the fourth sidewall 23 in each partition region 30 may change.

[0040] In contrast, in the partition member 1 with the continuous cut portion 50, the first ridge 11 and the second ridge 21 are cut off by the continuous cut portion 50. Therefore, if a thermal load is applied, the partition member 1 can be contracted at each of the first ridge 11 and the second ridge 21 that are cut off by the continuous cut portion 50. By contracting each of the first ridge 11 and the second ridge 21, each of the first ridge 11 and each of the second ridge 21 contracts in the direction of contraction of the first ridge and the second ridge itself (arrow direction shown in FIG8), thus suppressing the contraction of the partition member 1 toward the center as shown in FIG7. As a result, the change in distance from the light source to the first sidewall 12, the second sidewall 13, the third sidewall 22, and the fourth sidewall 23 in each partition region 30 is suppressed. As a result, the change in the direction of light reflection in the partition member 1 can be suppressed, thereby suppressing brightness unevenness and color unevenness in the planar light source.

[0041] The separator 1 is formed, for example, by stamping a sheet of polyethylene terephthalate (PET) or the like with a thickness of about 0.2 to 0.3 mm using a mold, thereby forming a shape having a first wall portion 10, a second wall portion 20, and a bottom portion 40. During forming, since the portion at intersection I is stretched the most, the stress based on the thermal load is the greatest at intersection I. Therefore, providing continuous cut portions 50 at intersection I to alleviate stress is particularly effective in suppressing the shrinkage of the separator 1 caused by the thermal load. In addition, setting the continuous cut portions 50 in a cross shape is effective in suppressing the shrinkage of the separator 1 in both the first direction X and the second direction Y. Furthermore, arranging continuous cut portions 50 at all intersection I of the separator 1 is effective in suppressing the overall shrinkage of the separator 1.

[0042] Furthermore, placing the first cutout 51 and the second cutout 52 at the intersection I has the following advantages compared to placing them outside the intersection I. That is, when the dividing area 30 is rectangular, the distance from the light source is greater at the intersection I compared to outside the intersection I. Therefore, when the dividing member is used in a planar light source, by providing the first cutout 51 and the second cutout 52 at a position farther from the light source, it is possible to make it difficult for light from the light source to reach the first cutout 51 and the second cutout 52, thereby suppressing the optical effects of uneven brightness.

[0043] Furthermore, in the separating member 1, each separating region 30 is rectangular when viewed from above. Since each separating region 30 has the same shape, it is possible to suppress the optical effects of uneven brightness. [Separating Member 1A]

[0044] Separator 1A is another example of a separator. Figure 9 is a partial top view illustrating separator 1A. Separator 1A is the same as separator 1 (see Figure 3, etc.) in that the continuous cutouts 50 are arranged in an alternating pattern.

[0045] Here, "interlaced" means that there are intersection points I where no continuous cuts 50 are provided between adjacent continuous cut portions 50 in the first direction X, and also between adjacent continuous cut portions 50 in the second direction Y. That is, in the separating member 1A, the continuous cut portions 50 are arranged at intersection points I adjacent to each other in the first direction X. Furthermore, the continuous cut portions 50 are arranged at intersection points I adjacent to each other in the second direction Y. No continuous cut portions 50 are provided at the intersection points I adjacent to each other in the first direction X and in the second direction Y.

[0046] Separator 1A is the same as separator 1 and can be used as a reflector for a planar light source. Since separator 1A has a continuous cutout 50, it can achieve the same effect as separator 1. [Separator 1B]

[0047] Separator 1B is another example of a separator. Figure 10 is a partial top view illustrating separator 1B. Separator 1B differs from separator 1 (see Figure 3, etc.) in that the first cut 51 and the second cut 52 are not continuous like the continuous cut 50, but are separated from each other.

[0048] In the partition member 1B, the first cut portion 51 and the second cut portion 52 are alternately arranged at a plurality of intersection points I on the first ridge 11 that intersect with the second ridge 21. Furthermore, the first cut portion 51 and the second cut portion 52 are alternately arranged at a plurality of intersection points I on the second ridge 21 that intersect with the first ridge 11. Alternatively, the first cut portion 51 and the second cut portion 52 may be alternately arranged only at either the plurality of intersection points I on the first ridge 11 that intersect with the second ridge 21, or the plurality of intersection points I on the second ridge 21 that intersect with the first ridge 11.

[0049] The first cutout portion 51 disposed at an intersection point I is disposed away from other intersection points I adjacent to that intersection point I. That is to say, the first cutout portion 51 disposed at an intersection point I does not reach other intersection points I adjacent to that intersection point I. It should be noted that the same applies to the second cutout portion 52.

[0050] The separating member 1B is the same as the separating member 1 and can be used as a reflector for a planar light source. Since the separating member 1B has a first cutout 51 and a second cutout 52, the same effect as the separating member 1 can be achieved in suppressing shrinkage. Furthermore, in the continuous cutout 50, the opening degree of the cutout near the intersection of the first cutout 51 and the second cutout 52 is relatively larger. Conversely, when the first cutout 51 and the second cutout 52 are arranged separately, the opening degree of the cutout can be reduced. Therefore, when the separating member 1B is used for a planar light source, the amount of light emitted from the light source and light returning from the optical sheet can be reduced from entering the first cutout 51 and the second cutout 52, thereby suppressing the decrease in the amount of light extracted from the planar light source. [Other variations of the separating member]

[0051] In the separating member, the first cut portion 51 and the second cut portion 52 may not be disposed at the intersection I, but may be disposed between adjacent intersection I without being connected to the intersection I. In this case, only the first cut portion 51 may be disposed, only the second cut portion 52 may be disposed, or both the first cut portion 51 and the second cut portion 52 may be disposed. In addition, the first cut portion 51 and the second cut portion 52 may be configured by arranging a plurality of points.

[0052] Furthermore, in the partition component, the shape of each partition area is not limited to a rectangle when viewed from above. For example, as shown in partition component 1C in FIG11 and partition component 1D in FIG12, the shape of each partition area 30 can be hexagonal when viewed from above.

[0053] In addition to a plurality of first wall portions 10 and a plurality of second wall portions 20, the partition members 1C and 1D also have a plurality of third wall portions 70. The plurality of third wall portions 70 are arranged in parallel to each other, for example. The partition members 1C and 1D may have a plurality of bottom portions 40 as needed.

[0054] The third wall portion 70 has a third ridge 71 extending upward in a third direction different from the first and second directions, a fifth side wall 72, and a sixth side wall 73. The fifth side wall 72 and the sixth side wall 73 are arranged separated by the third ridge 71 when viewed from above. The upper end of the fifth side wall 72 is continuous with the upper end of the sixth side wall 73. There is a space between the fifth side wall 72 and the sixth side wall 73.

[0055] The third ridge line 71 is the line connecting the highest point of the third wall portion 70. The area near the third ridge line 71 can be pointed or rounded in a cross-section cut in a direction orthogonal to the third ridge line 71. In addition, as described in the first ridge line 11, the third ridge line 71 can be a flat portion of extremely narrow width extending in a linear shape.

[0056] Separating members 1C and 1D have a first cutout 51 on a first ridge 11, a second cutout 52 on a second ridge 21, and a third cutout 53 on a third ridge 71. The first cutout 51, the second cutout 52, and the third cutout 53 are continuous, forming a continuous cutout portion 50C. In the continuous cutout portion 50C, the first cutout 51, the second cutout 52, and the third cutout 53 are continuous at the intersection point I of the first ridge 11, the second ridge 21, and the third ridge 71. In separating member 1C, the continuous cutout portion 50C is arranged at all intersection points I. In contrast, in separating member 1D, the continuous cutout portions 50C are arranged in an alternating pattern.

[0057] Thus, the separating members 1C and 1D each have a plurality of first wall portions 10 having a first ridge 11, a plurality of second wall portions 20 having a second ridge 21, and a plurality of third wall portions 70 having a third ridge 71 extending in a direction different from the first ridge 11 and the second ridge 21. The ends of the first ridge 11, the second ridge 21, and the third ridge 71 are connected to define the separating region 30. For example, if the separating region 30 is hexagonal when viewed from above, then each separating region 30 is arranged in a honeycomb shape when viewed from above. The separating region 30 may be a regular hexagon when viewed from above.

[0058] Figure 13 is a partial top view illustrating the partition member 1E, showing the lower left corner of the partition member 1E. As shown in the portion surrounded by the dashed line in Figure 13, a first peripheral cut 51E and a second peripheral cut 52E, different from the first cut 51 and the second cut 52, can be arranged on the outer periphery of the partition member 1E. The first peripheral cut 51E is a cut provided on the first edge 11 and located on the outer periphery of the partition member 1E. The second peripheral cut 52E is a cut provided on the second edge 21 and located on the outer periphery of the partition member 1E. The first peripheral cut 51E and the second peripheral cut 52E can be arranged orthogonally to the outer periphery of the partition member 1E.

[0059] In the separating member 1E, as an example, the first cutout portion 51 and the second cutout portion 52 are alternately arranged at a plurality of intersection points I on the first edge line 11 where they intersect with the second edge line 21. Alternatively, as an example, the first cutout portion 51 and the second cutout portion 52 are alternately arranged at a plurality of intersection points I on the second edge line 21 where they intersect with the first edge line 11. The outer peripheral first cutout portion 51E and the outer peripheral second cutout portion 52E may be arranged according to this rule or not. In the example shown in FIG13, all the outer peripheral first cutout portions 51E and the outer peripheral second cutout portions 52E are arranged orthogonally to the outer periphery. The lengths of the outer peripheral first cutout portions 51E and the outer peripheral second cutout portions 52E are shorter than the lengths of the first cutout portion 51 and the second cutout portion 52 in the example shown in FIG13. The lengths of the first peripheral cut 51E and the second peripheral cut 52E can, for example, be set to approximately half the lengths of the first cut 51 and the second cut 52. It should be noted that the first peripheral cut 51E and the second peripheral cut 52E can be formed simultaneously with the first cut 51 and the second cut 52, or they can be formed in a separate process from the first cut 51 and the second cut 52. By simultaneously forming the first peripheral cut 51E, the second peripheral cut 52E, the first cut 51, and the second cut 52, productivity can be improved.

[0060] The partition member can be rectangular in shape when viewed from above, as shown in the example of FIG1, or it can be irregularly shaped. FIG14 is a partial top view illustrating a partition member 1F that is irregularly shaped when viewed from above, showing the lower left corner of the partition member 1F. Here, irregular shape refers to a shape other than a rectangle when viewed from above, such as a shape that applies partial or overall deformation to a complete rectangle to conform to a specific product shape. The outer perimeter of the partition member can be composed of only a plurality of straight lines, as shown in the example of FIG14, or it can include curves. In the partition member 1F, there is an area in the lower left corner where no partition area is configured.

[0061] In the partition member 1F, as an example, at a plurality of intersection points I on the first edge 11 where it intersects with the second edge 21, the first cut portion 51 and the second cut portion 52 are alternately arranged. Alternatively, as an example, at a plurality of intersection points I on the second edge 21 where it intersects with the first edge 11, the first cut portion 51 and the second cut portion 52 are alternately arranged. Similar to the partition member 1E, the outer peripheral first cut portion 51E and the outer peripheral second cut portion 52E can be arranged according to this rule, or they can be arranged without following the rule. In the example shown in FIG. 14, all the outer peripheral first cut portions 51E and the outer peripheral second cut portions 52E are arranged orthogonally to the outer periphery.

[0062] Furthermore, the continuous cut portion at the intersection of the first ridge 11 and the second ridge 21 of the separating member can be arranged along the first ridge 11 and the second ridge 21, or it can be arranged without following the first ridge 11 and the second ridge 21. When the continuous cut portion is not arranged along the first ridge 11 and the second ridge 21, the first cut portion 51 and the second cut portion 52 of the continuous cut are arranged on the side wall.

[0063] Furthermore, when the first cutout 51 is positioned at the intersection of the first ridge line 11 and the second ridge line 21, in a top view, the first cutout 51 can extend from a position through the lower end of the third sidewall 22 and parallel to the Y direction to a position through the lower end of the fourth sidewall 23 and parallel to the Y direction. Similarly, when the second cutout 52 is positioned at the intersection of the first ridge line 11 and the second ridge line 21, in a top view, the second cutout 52 can extend from a position through the lower end of the first sidewall 12 and parallel to the X direction to a position through the lower end of the second sidewall 13 and parallel to the X direction.

[0064] Furthermore, when a plurality of first cut portions 51 are arranged on the first ridge 11, the length of each first cut portion 51 can be the same, or the cut portion of the first cut portion 51 located further outward can be longer. Since the shrinkage of the separating member is greater on the outer periphery, by setting the length of the cut portion of the first cut portion 51 located further outward can the shrinkage on the outer periphery be suppressed. The same applies when a plurality of second cut portions 52 are arranged on the second ridge 21. That is, when a plurality of second cut portions 52 are arranged on the second ridge 21, the length of each second cut portion 52 can be the same, or the cut portion of the second cut portion 52 located further outward can be longer. In addition, when a plurality of first cut portions 51 are arranged on the first ridge 11 and a plurality of second cut portions 52 are arranged on the second ridge 21, the length of the cut portion of the first cut portion 51 and the second cut portion 52 located closer to the corner of the separating member can be set to be longer. This can inhibit peripheral contraction.

[0065] Furthermore, in the separating member, it is sufficient to provide at least one first cutout on at least one first edge line; a second cutout on the second edge line is not required. Alternatively, in the separating member, at least one first cutout may be provided on at least one first edge line, and at least one second cutout may be provided on at least one second edge line. [Planar Light Source 60]

[0066] The aforementioned separating member can be disposed on a substrate and bonded to the substrate to form a planar light source. Here, although the planar light source is described using separating member 1 as an example, other separating members such as separating members 1A and 1B can be used instead of separating member 1. In addition, a plurality of separating members can be arranged on a substrate.

[0067] FIG15 is a top view illustrating the planar light source according to an example of the first embodiment. FIG16 is a cross-sectional view along line XVI-XVI of FIG15. As shown in FIG15 and FIG16, the planar light source 60 is a surface-emitting type light-emitting device having a substrate 61, a covering member 62, a separating member 1, and a plurality of light sources 63. The separating member 1 is disposed on the substrate 61. The covering member 62 covers at least a portion of the upper surface of the substrate 61. The covering member 62 is provided as needed.

[0068] In the planar light source 60, the lower surface of the bottom 40 of the separating member 1 is joined to the covering member 62 disposed on the substrate 61. That is, the lower surface of the bottom 40 of the separating member 1 is indirectly joined to the substrate 61 through the covering member 62. Furthermore, in the planar light source 60, the light source 63 is disposed on the substrate 61 exposed within the opening 40x of the bottom 40. Hereinafter, the components included in the planar light source 60 will be described in detail. (Substrate 61)

[0069] The substrate 61 is a component for mounting a plurality of light sources 63. Conductor wirings 68A and 68B for supplying power to the light sources 63 are disposed on the upper surface 61m of the substrate 61. Preferably, the covering member 62 covers a portion of the conductor wirings 68A and 68B that are not electrically connected to the light-emitting elements.

[0070] The material of the substrate 61 should be sufficient to insulate and separate at least one pair of conductor wires 68A and 68B. Examples of suitable materials include ceramics, resins, and composite materials. Examples of suitable resins include phenolic resins, epoxy resins, polyimide resins, BT resins, polyphthalamide (PPA), and polyethylene terephthalate (PET). Examples of suitable composite materials include materials in which inorganic fillers such as glass fibers, SiO2, TiO2, and Al2O3 are mixed into the aforementioned resins, glass fiber reinforced resins (glass epoxy resins), and metal substrates with an insulating layer covering the metal parts.

[0071] The thickness of the substrate 61 can be appropriately selected. The substrate 61 can be either a flexible substrate or a rigid substrate that can be manufactured by a roll-to-roll method. The rigid substrate can be a thin, flexible rigid substrate. The conductor wires 68A and 68B can be conductive components, and the materials are not particularly limited; materials commonly used as wiring layers in circuit boards, etc., can be used. The surfaces of the conductor wires 68A and 68B can be provided with light-reflecting films, etc.

[0072] Preferably, the cover member 62 is made of an insulating material. The same material as that shown as the material of the substrate 61 can be used as the material for the cover member 62. By using a material containing a white, light-reflective filler or many air bubbles in the resin, the light emitted from the light source 63 is reflected, thereby improving the light extraction efficiency of the planar light source 60. (Light source 63)

[0073] The light source 63 is a component for emitting light, including, for example, a self-emitting light-emitting element itself, a component that seals the light-emitting element with a light-transmitting resin, and a surface-mount type light-emitting device (also known as an LED) after the light-emitting element is encapsulated. For example, as shown in FIG16, a component that covers the light-emitting element 63a with a sealing component 63b can be used as the light source 63. The light source 63 can use one light-emitting element 63a, or it can use a plurality of light-emitting elements as one light source 63. For example, a component that emits blue light can be used. In addition, the light source 63 can be configured to include the following components: a resin including a light-reflective material surrounding the side of the light-emitting element; and a light-transmitting component covering the upper surface of the light-emitting element and the upper surface of the resin including the light-reflective material. It can also be configured to include a light-transmitting component covering the upper surface of the light-emitting element, and a resin including a light-reflective material surrounding the side of the light-emitting element and the side of the light-transmitting component. The light-transmitting component here may include a phosphor. A transparent adhesive component can be provided between the light-emitting element and the light-transmitting component to bond the light-emitting element and the light-transmitting component together.

[0074] In order to illuminate each of the partition regions 30 of the partition member 1 with less uneven brightness, the light source 63 is preferably wide-spectrum. In particular, it is preferable that each light source 63 has a batwing-shaped light distribution characteristic. As a result, by suppressing the amount of light emitted in the direction directly above the light source 63, the light distribution of each light source 63 is broadened, and the broadened light illuminates the first sidewall 12, the second sidewall 13, the third sidewall 22, the fourth sidewall 23 and the bottom 40, thereby suppressing uneven brightness in each partition region 30.

[0075] Here, the batwing-shaped light distribution characteristic is defined as follows: when the optical axis OA is set to 0 degrees, the light distribution has a stronger light intensity distribution than 0 degrees at angles where the absolute value of the light distribution angle is greater than 0 degrees. It should be noted that, as shown in Figure 16, the optical axis OA is defined as the line that passes through the center of the light source 63 and intersects perpendicularly with the upper surface 61m of the substrate 61.

[0076] In particular, as a light source 63 with batwing-shaped light distribution characteristics, for example, as shown in FIG16, a light source using a light-emitting element 63a having a light-reflecting film 63c on its upper surface can be cited. By providing a light-reflecting film 63c on the upper surface of the light-emitting element 63a, light directed upwards toward the light-emitting element 63a is substantially reflected by the light-reflecting film 63c, and the amount of light directly above the light-emitting element 63a is suppressed, thus obtaining batwing-shaped light distribution characteristics. A lens can also be separately assembled for setting the light distribution to batwing shape.

[0077] The light-reflecting film 63c can be any of the following: a metal film such as silver or copper, a material containing a white filler in a resin, or a combination thereof. Furthermore, the light-reflecting film 63c is configured as a dielectric multilayer film (DBR film), and its reflectivity can be angle-dependent with respect to the emission wavelength of the light-emitting element 63a. Specifically, it is preferable that the reflectivity of the light-reflecting film 63c is set such that it is lower when incident at an angle compared to perpendicular incidence. This moderates the brightness variation on the surface of the light-emitting element 63a, suppressing extreme dimming or darkening of the surface of the light-emitting element 63a.

[0078] As the light source 63, for example, the height of the light-emitting element 63a, which is directly mounted on the substrate 61, can be 100 μm to 500 μm. The thickness of the light-reflecting film 63c can be 0.1 μm to 3.0 μm. Even including the sealing member 63b, the thickness of the light source 63 can be set to about 0.5 mm to 2.0 mm.

[0079] Preferably, the wiring on the substrate 61 is performed in such a manner that a plurality of light sources 63 can be driven independently of each other, and that dimming control (e.g., local dimming or high dynamic range) is possible for each light source 63. (Light-emitting element 63a)

[0080] Known components can be used as the light-emitting element 63a. For example, a light-emitting diode is preferably used as the light-emitting element 63a. The light-emitting element 63a can be selected with any wavelength. For example, as a blue or green light-emitting element, a light-emitting element using nitride semiconductors such as GaN, InGaN, AlGaN, and AlInGaN can be used. In addition, as a red light-emitting element, GaAlAs, AlInGaP, etc. can be used. Moreover, semiconductor light-emitting elements made of materials other than these can also be used. The composition, color, size, number, etc. of the light-emitting element used can be appropriately selected according to the purpose.

[0081] As shown in FIG16, the light-emitting element 63a can be flip-chip mounted across the bonding member 69 by means of a pair of positive and negative conductor wires 68A and 68B provided on the upper surface 61m of the substrate 61. However, the light-emitting element 62a is not limited to flip-chip mounting, and can also be mounted face-up.

[0082] The bonding member 69 is a component used to bond the light-emitting element 63a to a substrate or conductor wiring. Examples include insulating resins or conductive components. In the case of flip-chip mounting as shown in FIG. 16, conductive components can be used. Specifically, examples include alloys containing Au, Ag, Pd, In, Pb-Pd, Au-Ga, Au-Sn, Sn, Sn-Cu, Sn-Cu-Ag, Au-Ge, Au-Si, Al, Cu-In, and mixtures of metals and flux. (Sealing member 63b)

[0083] The sealing member 63b covers the light-emitting element 63a for purposes such as protecting the light-emitting element 63a from the external environment and optically controlling the light emitted by the self-emitting element 63a (e.g., obtaining batwing-shaped light distribution characteristics). The sealing member 63b is made of a light-transmitting material. As the material of the sealing member 63b, light-transmitting resins such as epoxy resins, silicone resins, or mixtures thereof, as well as glass, can be used. Among these, silicone resin is preferred considering light resistance and ease of molding. The sealing member 63b may include a diffusing agent for diffusing light from the light-emitting element 63a, a colorant corresponding to the emission color of the light-emitting element 63a, etc. The diffusing agent and colorant, etc., can be substances known in the art.

[0084] The sealing member 63b can directly contact the substrate 61. The sealing member 63b is adjusted to a viscosity suitable for printing, dispensing, etc., and can be cured by heat treatment or light irradiation. Examples of the shape of the sealing member 63b include, for example, a generally hemispherical shape, a longitudinally elongated convex shape in cross-section, a flattened convex shape in cross-section, a circular shape or an elliptical shape in top view, but it is not limited to these. Here, a longitudinally elongated convex shape refers to a shape in cross-section where, compared to the maximum length in the direction parallel to the upper surface 61m of the substrate 61, the maximum length in the direction perpendicular to the upper surface 61m of the substrate 61 is longer. Conversely, a flattened convex shape refers to a shape in cross-section where, compared to the maximum length in the direction perpendicular to the upper surface 61m of the substrate 61, the maximum length in the direction parallel to the upper surface 61m of the substrate 61 is longer. The sealing member 63b can be disposed as a bottom filler 63d between the lower surface of the light-emitting element 63a and the upper surface 61m of the substrate 61. (Separator 1)

[0085] The separating member 1 is disposed on the substrate 61. A space is provided between the lower surface of the first sidewall 12 and the lower surface of the second sidewall 13 and the upper surface of the substrate 61 or the upper surface of the covering member 62. In addition, a space is provided between the lower surface of the third sidewall 22 and the lower surface of the fourth sidewall 23 and the upper surface of the substrate 61 or the upper surface of the covering member 62.

[0086] In the partition member 1, each opening 40x is disposed in the center of each partition region 30. Preferably, the shape and size of each opening 40x are such that the light source 63 is fully exposed, and preferably the outer edge of each opening 40x is set to be located only near the light source 63. Thus, when the partition member 1 is light reflective, light from the light source 63 can also be reflected at each bottom 40, thereby improving the light extraction efficiency. It should be noted that in the partition member 1, each opening 40x can be formed before the formation of the first cut 51 and the second cut 52, after the formation of the first cut 51 and the second cut 52, or simultaneously with the first cut 51 and the second cut 52.

[0087] In FIG16, the angle α formed by the adjacent third sidewall 22 and fourth sidewall 23 is preferably set to, for example, 60 degrees to 90 degrees. By setting the angle α to such a range, the space and area occupied by the partition member 1 are reduced, and the height of the partition member 1 can be reduced, thereby enabling the planar light source 60 to be made thinner. The same applies to the angle formed by the adjacent first sidewall 12 and second sidewall 13.

[0088] The spacing between adjacent first ridges 11 and adjacent second ridges 21 can be appropriately adjusted according to the size of the light source used, the size of the required planar light source, etc. For example, the spacing between adjacent first ridges 11 and adjacent second ridges 21 can be 1mm to 50mm, preferably 5mm to 20mm, and more preferably 6mm to 15mm.

[0089] In addition, the height H of the partition member 1 itself, that is, the length in the Z direction from the lower surface of each bottom 40 of the partition member 1 to the first ridge 11 or the second ridge 21, is preferably 8 mm or less, and is preferably about 1 mm to 4 mm when it is set as a thinner planar light source.

[0090] Preferably, the separating member 1 is bonded to the substrate 61 using an adhesive member. Therefore, even if the separating member 1 shrinks due to heat, the shrinkage of the separating member 1 can be suppressed because it is bonded to the substrate 61 by the adhesive member. The separating member 1 can be bonded around each opening 40x using a light-reflective adhesive member, so that the emitted light from the light source 63 does not incident between the substrate 61 and the separating member 1. For example, it is more preferable to arrange the light-reflective adhesive member in a ring shape along the outer edge of each opening 40x. The adhesive member can be, for example, double-sided tape with an acrylic resin adhesive applied to both sides of a PET substrate, a hot-melt adhesive sheet, or a resin-based adhesive such as a thermosetting resin or thermoplastic resin. Preferably, these adhesive members have high flame retardancy.

[0091] As described above, the partition member 1 preferably has light reflectivity. As a result, light emitted from the light source 63 can be efficiently reflected upwards by the first sidewall 12, the second sidewall 13, the third sidewall 22, the fourth sidewall 23 and the bottom 40.

[0092] The separating member 1 can be molded using a resin containing a reflective material such as titanium dioxide, aluminum oxide, or silicon oxide particles, or it can be molded using a resin without a reflective material and then have a reflective material applied to its surface. Alternatively, a resin comprising a plurality of tiny air bubbles can be used. In this case, light is reflected at the interface between the air bubbles and the resin. Furthermore, examples of resins used in the separating member 1 include thermoplastic resins such as acrylic resins, polycarbonate resins, cyclic polyolefin resins, polyethylene terephthalate, polyethylene naphthalate, or polyesters, or thermosetting resins such as epoxy resins or silicone resins. Preferably, the separating member 1 is configured to have a reflectivity of 70% or higher for light emitted from the light source 63.

[0093] The partition member 1 can be formed by a molding method using a metal mold, a molding method based on photoforming, or by purchasing a partition member 1 having each first wall portion 10, each second wall portion 20, and each bottom portion 40. As a molding method using a metal mold, molding methods such as injection molding, extrusion molding, compression molding, vacuum forming, and stamping can be applied. For example, a partition member 1 with each first wall portion 10, each second wall portion 20, and each bottom portion 40 integrally formed can be obtained by vacuum forming using a reflective sheet made of PET or the like.

[0094] It should be noted that the planar light source 60, as an optical component disposed above the light source 63 with the separating member 1 in between, may include a diffuser. By having a diffuser, the uniformity of light emitted from the planar light source 60 to the outside can be improved. Furthermore, the planar light source 60 may further have at least one selected from the group consisting of a wavelength conversion plate, a first prism sheet, a second prism sheet, and a polarizer above the diffuser. By having one or more of these optical components, the uniformity of light can be further improved. It should be noted that the wavelength conversion plate, for example, absorbs a portion of the blue light from the light source and emits yellow, green, and / or red light, and emits white light. Since the wavelength conversion plate is separated from the light-emitting element 63a of the light source 63, phosphors or other materials that are difficult to use near the light-emitting element 63a and have poor heat or light intensity resistance can be used. Therefore, the performance of the backlight of the planar light source 60 is improved. The fluorescein contained in the wavelength conversion sheet can be yttrium aluminum garnet fluorescein (e.g., Y3(Al,Ga)5O12:Ce), ruthenium aluminum garnet fluorescein (e.g., Lu3(Al,Ga)5O12:Ce), thallium aluminum garnet fluorescein (e.g., Tb3(Al,Ga)5O12:Ce), CCA fluorescein (e.g., Ca10(PO4)6Cl2:Eu), SAE fluorescein (e.g., Sr4Al14O25:Eu), chlorosilicone fluorescein (e.g., Ca8MgSi4O16Cl2:Eu), β-silicon fluorescein (e.g., (Si,Al)3(O,N)4:Eu), α-silicon fluorescein (e.g., Ca(Si,Al)12(O,N)16:Eu), S... Nitride fluores such as LA-type fluoresceins (e.g., SrLiAl3N4:Eu), CASN-type fluoresceins (e.g., CaAlSiN3:Eu), or SCASN-type fluoresceins (e.g., (Sr,Ca)AlSiN3:Eu), KSF-type fluoresceins (e.g., K2SiF6:Mn), KSAF-type fluoresceins (e.g., K2(Si0.99,Al0.01)F65.99:Mn), or MGF-type fluoresceins (e.g., 3.5MgO･0.5MgF2･GeO2:Mn), perovskite-structured fluoresceins (e.g., CsPb(F,Cl,Br,I)3), or quantum dot fluoresceins (e.g., CdSe, InP, AgInS2, or AgInSe2), etc. It should be noted that when the sealing component 63b contains a phosphor, the phosphor can be made of the aforementioned material.

[0095] The planar light source 60 can be a shape parallel to the XY plane, or it can be a shape curved towards the Z+ or Z- side relative to the XY plane. For example, in the X direction, the center of the planar light source 60 can be a curved shape that is concave towards the Z- side. <Example>

[0096] First, a planar light source A with the same structure as the planar light source 60 shown in FIG. 15 is manufactured. In the planar light source A, a partition member with a rectangular shape identical to the partition member 1 shown in FIG. 1 and having cutouts identical to those of the partition member 1B shown in FIG. 10 is used. That is, a partition member is used in which the first cutout and the second cutout are alternately arranged at a plurality of intersection points on the first edge line intersecting with the second edge line, and the first cutout and the second cutout are alternately arranged at a plurality of intersection points on the second edge line intersecting with the first edge line. However, on the outer periphery of the partition member, an outer peripheral first cutout and an outer peripheral second cutout orthogonal to the outer periphery edge are arranged. It should be noted that the lengths of the first cutout and the second cutout are set to approximately 3 mm, and the lengths of the outer peripheral first cutout and the outer peripheral second cutout are set to approximately 1.5 mm.

[0097] In addition, as a comparative example, a planar light source B with the same structure as planar light source A was manufactured, except that no cutout was provided in the partition member. In both planar light source A and planar light source B, the partition member is formed of the same material. Polyethylene terephthalate (PET) was used as the material for the partition member.

[0098] For planar light source A and planar light source B, the dimensions of the separation component in the length direction (X direction) and width direction (Y direction) were measured as initial data, and both were X=225mm and Y=127mm.

[0099] Next, planar light source A and planar light source B were stored at 100°C. After 1000 hours, the dimensions of the separating component in the X and Y directions were measured, and the degree of shrinkage was investigated. The results are shown in Table 1. (Table 1)

[0100] As shown in Table 1, in the planar light source A with a notch in the separating member, the dimension of the separating member in the X direction shrinks by 0.16 mm, and the dimension in the Y direction shrinks by 0.12 mm. Expressed as a shrinkage rate, this is 0.07% in the X direction and 0.26% in the Y direction. In contrast, in the planar light source B without a notch in the separating member, the dimension of the separating member in the X direction shrinks by 0.63 mm, and the dimension in the Y direction shrinks by 0.42 mm. Expressed as a shrinkage rate, this is 0.28% in the X direction and 0.92% in the Y direction.

[0101] Thus, it can be confirmed that by providing a slit in the partition member, compared to the case where no slit is provided in the partition member, the shrinkage of the partition member in the X and Y directions under high temperature conditions can be suppressed to approximately 1 / 3 to 1 / 4. <Second Embodiment>

[0102] In the second embodiment, an example of a separator component with a structure in which two components overlap is shown. [Separator Component 2]

[0103] Figure 17 is a partial top view (1) illustrating the partition member 2. Figure 18 is a partial top view (2) illustrating the partition member 2, showing the filling before the two members are overlapped. The partition member 2 shown in Figure 17 has a lower member 1G disposed below the partition member 1A shown in Figure 18.

[0104] That is to say, the partition member 2 has a partition member 1A and a lower member 1G disposed on the lower side of the partition member 1A. In the partition member 2, the partition member 1A is disposed overlapping the lower member 1G. The overall shape of the partition member 1A is the same as that of the partition member 1 shown in FIG1, etc., and the position and shape of the cut are the same as those described with reference to FIG9.

[0105] The lower component 1G has a plurality of fourth wall portions 110 and a plurality of fifth wall portions 120. In the example of FIG. 18, the lower component 1G has a plurality of bottom portions 140, and each bottom portion 140 is provided with an opening 140x. It should be noted that either the partition member 1A or the lower component 1G may have a bottom portion and an opening, or both may have a bottom portion and an opening. When both the partition member 1A and the lower component 1G have a bottom portion and an opening, and the partition member 1A is superimposed on the lower component 1G, a bottom portion 40 is disposed on the upper side of the bottom portion 140, and the opening 40x communicates with the opening 140x.

[0106] The fourth wall portion 110 has a fourth ridge line 111 extending in a first direction, a seventh side wall 112, and an eighth side wall 113. The upper end of the seventh side wall 112 is continuous with the upper end of the eighth side wall 113. There is a space between the seventh side wall 112 and the eighth side wall 113.

[0107] The fourth ridge line 111 is the line connecting the highest point of the fourth wall portion 110. In a cross-section cut in a direction orthogonal to the fourth ridge line 111, the area near the fourth ridge line 111 can be a pointed shape or a shape with rounded corners. In addition, as described with the first ridge line 111, the fourth ridge line 111 can be a flat portion of extremely narrow width extending in a linear shape.

[0108] Each fourth wall portion 110 is disposed on the lower side of each first wall portion 10 of the partition member 1A.

[0109] The fifth wall portion 120 has a fifth ridge line 121 extending in a second direction intersecting the first direction, a ninth side wall 122, and a tenth side wall 123. The upper end of the ninth side wall 122 is continuous with the upper end of the tenth side wall 123. There is a space between the ninth side wall 122 and the tenth side wall 123.

[0110] The fifth ridge line 121 is the line connecting the highest point of the fifth wall portion 120. In a cross-section cut in a direction orthogonal to the fifth ridge line 121, the area near the fifth ridge line 121 can be a pointed shape or a shape with rounded corners. In addition, as described with the first ridge line 11, the fifth ridge line 121 can be a flat portion of extremely narrow width extending in a linear shape.

[0111] Each fifth wall portion 120 is disposed on the underside of each second wall portion 20 of the partition member 1A.

[0112] The lower component 1G, when viewed from above, has a continuous lower cutout 150 consisting of a first lower cutout 151 on the fifth ridge 121 and a second lower cutout 152 on the fourth ridge 111. The first lower cutout 151 is, for example, a straight line extending in the second direction Y, and the second lower cutout 152 is, for example, a straight line extending in the first direction X. The lengths of the first lower cutout 151 and the second lower cutout 152 may be the same or different.

[0113] When viewed from above, the continuous cut on the lower side 150 is cross-shaped.

[0114] In the partition member 1A, the continuous cut portions 50 are arranged in an alternating manner. In the lower member 1G, the lower continuous cut portions 150 are arranged in an alternating manner and are positioned at a position that does not coincide with the continuous cut portions 50 of the partition member 1A when viewed from above, after the lower member 1G overlaps the partition member 1A.

[0115] The partition member 1A may or may not be adhered to the lower member 1G. When the partition member 1A is adhered to the lower member 1G, adhesive, double-sided tape, etc., can be used. For example, when both the partition member 1A and the lower member 1G have bottoms, the bottom 40 of the partition member 1A can be adhered to the bottom 140 of the lower member 1G. Alternatively, the partition member 1A and the lower member 1G may not be adhered to each other at their bottoms, but their walls may be adhered to each other. Alternatively, the partition member 1A and the lower member 1G may be adhered to each other at their bottoms, and their walls may be further adhered to each other.

[0116] The lower component 1G may be the same size as the partition component 1A, or it may be a different size. For example, the lower component 1G may be configured such that its wall is connected to the wall of the partition component 1A, and its bottom is connected to the bottom of the partition component 1A. It should be noted that the same applies to the lower component 1H described later; it may be the same size as the partition component 1B, or it may be a different size.

[0117] Thus, in the partition member 2, when viewed from above, a continuous cutout portion 50 and a lower continuous cutout portion 150 are arranged at positions that do not overlap with each other. Therefore, when the partition member 2 is used for a planar light source, the same effect as that of the partition member 1 can be achieved in suppressing the shrinkage of the partition member 2.

[0118] Furthermore, when the separating member 2 is used for a planar light source, the light emitted from the light source and the light returning from the optical sheet, etc., passing through the cutout portion of the separating member 1A, is reflected by the lower member 1G. Therefore, compared to the case shown in FIG3 where continuous cutout portions 50 are provided at all intersection points I of the separating member 1, the reduction in the amount of light extracted from the planar light source can be suppressed. [Separating member 2A]

[0119] Figure 19 is a partial top view (1) illustrating a partition member 2A. Figure 20 is a partial top view (2) illustrating a partition member 2A, showing the state before the two members are overlapped. The partition member 2A shown in Figure 19 has a lower member 1H disposed below the partition member 1B shown in Figure 20. The positional relationship of the cutouts in the example partition member 2A shown in Figure 19 is different from that of the partition member 2 shown in Figure 17.

[0120] In the partition member 2A, the partition member 1B overlaps on the lower member 1H. When viewed from above, the first cut 51 intersects with the first lower cut 151, and the second cut 52 intersects with the second lower cut 152. For example, when viewed from above, the first cut 51 and the first lower cut 151 intersect in a cross shape, and the second cut 52 and the second lower cut 152 intersect in a cross shape.

[0121] Thus, in the partition member 2A, when viewed from above, at all intersection points I, the first cut 51 intersects with the first lower cut 151 or the second cut 52 intersects with the second lower cut 152. Therefore, when the partition member 2A is used for a planar light source, the same effect as that of the partition member 1 can be achieved in suppressing the shrinkage of the partition member 2A.

[0122] Furthermore, when the separating member 2A is used for a planar light source, a portion of the light emitted by the light source and the light returning from the optical sheet, etc., passing through the cut portion of the separating member 1B, is reflected by the lower member 1H. Therefore, compared to the case where continuous cut portions 50 are provided at all intersections I of the separating member 1 shown in FIG3, the reduction in the amount of light extracted from the planar light source can be suppressed. It should be noted that the effect of the separating member 2, where the continuous cut portions 50 are completely blocked by the lower member 1G, is greater than the effect of the separating member 2A in suppressing the reduction in the amount of light extracted. [Modifications of the Second Embodiment]

[0123] In the partition member 2, at least one continuous cutout 50 may be provided in the partition member 1A, and at least one lower continuous cutout 150 may be provided at a position that does not coincide with the continuous cutout 50 when viewed from above in the lower member 1G. <Third Embodiment>

[0124] In the third embodiment, an example of a liquid crystal display device (liquid crystal display device) in which a planar light source 60 is used as a backlight source is shown.

[0125] FIG21 is a configuration diagram illustrating a liquid crystal display device according to an example of a third embodiment. As shown in FIG21, the liquid crystal display device 1000 includes, from top to bottom, a liquid crystal panel 720, an optical sheet 710, and a planar light source 60. It should be noted that the planar light source 60 may have a DBEF (reflective polarizer), a BEF (brightness enhancer), a color filter, etc., as optical components above the light source 63.

[0126] The liquid crystal display device 1000 is a so-called directly-mounted liquid crystal display device in which a planar light source 60 is stacked below the liquid crystal panel 720. The liquid crystal display device 1000 illuminates the liquid crystal panel 720 with light emitted from the planar light source 60. From the viewpoint of thinning the planar light source, the thickness of the planar light source can be set to 15 mm or less. As a result, the planar light source is thinner, and the liquid crystal display device 1000 can be made thinner.

[0127] The planar light source 60 is not limited to being used as a backlight for the LCD display device 1000. The planar light source 60 can also be used as a backlight for televisions, tablets, smartphones, smartwatches, head-up displays, digital signage, billboards, etc. In addition, the planar light source 60 can be used as a light source for illumination, such as emergency lights, linear lighting, or various colored lights, and for vehicle mounting, etc.

[0128] Although the preferred embodiments have been described in detail above, they are not limited to the above embodiments and do not exceed the scope described in the claims. Various modifications and substitutions can be applied to the above embodiments. [Simplified Explanation of the Diagram]

[0008] Figure 1 is a top view illustrating the partition member 1. Figure 2 is a cross-sectional view along line II-II of Figure 1. Figure 3 is a partial top view of region A in Figure 1. Figure 4 is a cross-sectional view along line IV-IV of Figure 3. Figure 5 is a cross-sectional view (1) illustrating another example of a continuous cut. Figure 6 is a cross-sectional view (2) illustrating another example of a continuous cut. Figure 7 is a diagram illustrating thermal load-based shrinkage in the partition member 1X of the comparative example. Figure 8 is a diagram illustrating the suppression of thermal load-based shrinkage in the partition member 1. Figure 9 is a partial top view illustrating the partition member 1A. Figure 10 is a partial top view illustrating the partition member 1B. Figure 11 is a partial top view illustrating the partition member 1C. Figure 12 is a partial top view illustrating the partition member 1D. Figure 13 is a partial top view illustrating the partition member 1E. Figure 14 is a partial top view illustrating the partition member 1F. Figure 15 is a top view illustrating the planar light source of the first embodiment. Figure 16 is a cross-sectional view along line XVI-XVI of Figure 15. Figure 17 is a partial top view (1) of the separator 2 as an example. Figure 18 is a partial top view (2) of the separator 2 as an example. Figure 19 is a partial top view (1) of the separator 2A as an example. Figure 20 is a partial top view (2) of the separator 2A as an example. Figure 21 is a configuration diagram of the liquid crystal display device according to the third embodiment as an example.

Claims

1. A planar light source comprising: a substrate; a plurality of light sources disposed on the substrate; and at least one partition member disposed on the substrate, the partition member comprising: a plurality of first wall portions having first ridges extending with a constant width in a first direction; a plurality of second wall portions having second ridges extending with a constant width in a second direction intersecting the first direction; and partition regions comprising two opposing first wall portions and two opposing second wall portions, and being surrounded by the first ridges and the second ridges when viewed from above, the partition regions comprising a plurality of partition regions disposed in the first direction and the second direction, at least one first cutout being provided on at least one of the first ridges, and the light sources being disposed in the partition regions respectively.

2. As in request item 1, a planar light source, wherein, At least one second cut is provided on at least one of the second ridge lines.

3. As in claim 2, a planar light source, wherein, When viewed from above, the first cut and the second cut are separated from each other.

4. As in request item 3, a planar light source, wherein, At a plurality of intersection points on the first ridge line where it intersects with the second ridge line, the first cut portion and the second cut portion are alternately arranged.

5. As in request item 3 or 4, a planar light source, wherein, At a plurality of intersection points on the second ridge line where it intersects with the first ridge line, the first cut portion and the second cut portion are alternately arranged.

6. As in request item 5, a planar light source, wherein, It also has a lower side member disposed on the lower side of the partition member, the lower side member having: a plurality of fourth wall portions having fourth ridges extending in the first direction and disposed on the lower side of each of the first wall portions; and a plurality of fifth wall portions having fifth ridges extending in the second direction and disposed on the lower side of each of the second wall portions; a first lower side cutout that intersects the first cutout when viewed from above is provided on the fifth ridge, and a second lower side cutout that intersects the second cutout when viewed from above is provided on the fourth ridge.

7. As in request item 6, a planar light source, wherein, The second wall portion has a third sidewall and a fourth sidewall disposed between the second ridge line, and at least a portion of the third sidewall and the fourth sidewall are connected between the second cut portion.

8. A planar light source comprising: a substrate; a plurality of light sources disposed on the substrate; and at least one partition member disposed on the substrate, the partition member comprising: a plurality of first wall portions having a first ridge extending with a constant width in a first direction; a plurality of second wall portions having a second ridge extending with a constant width in a second direction intersecting the first direction; a plurality of third wall portions having a third ridge extending with a constant width in a direction different from the first ridge and the second ridge; and hexagonal partition regions defined by the connection of the ends of the first ridge, the second ridge, and the third ridge, the partition regions being honeycomb-shaped in a top view, at least one first cutout being provided on at least one of the first ridges; and the first wall portion having a first sidewall and a second sidewall disposed between the first ridge, the first sidewall and the second sidewall being at least partially connected through the first cutout, the light sources being respectively disposed within the partition regions.

9. A partition member comprising: a plurality of first wall portions having a first ridge extending with a constant width in a first direction; a plurality of second wall portions having a second ridge extending with a constant width in a second direction intersecting the first direction; and a partition region comprising two opposing first wall portions and two opposing second wall portions, and being surrounded by the first ridge and the second ridge when viewed from above, the partition region being arranged in a plurality of such portions in the first direction and the second direction, and at least one first cutout being arranged on at least one of the first ridges.

10. As in claim 9, the separating component, wherein, At least one second cut is provided on at least one of the second ridge lines.

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