Section member, surface light source and liquid crystal display device

Abstract

To suppress a section member from thermally shrinking in a surface light source which has the partition member.SOLUTION: A surface light source has a substrate, a plurality of light sources arranged on the substrate, and at least one section member arranged on the substrate. The section member has a plurality of first wall parts having a first ridge extending in a first direction, a plurality of second wall parts having a second ridge extending in a second direction crossing the first direction, and a section region including two opposite first wall parts and two opposite second wall parts, and is surrounded with the first ridge and second ridge in plan view. A plurality of section regions are arranged in the first direction and second direction, at least one first cut part is provided on at least one first ridge, and the light sources are arranged in the section regions respectively.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a partition member, a surface light source, and a liquid crystal display device. [Background technology]

[0002] There is known an illumination device that includes a substrate on which a plurality of light-emitting elements are arranged, and a reflecting member provided on the substrate. In this illumination device, the light-emitting elements are arranged in each opening provided in the reflecting member. In this illumination device, the reflecting member may thermally shrink in a high-temperature environment, causing uneven brightness, so measures are taken to reduce the effect of thermal shrinkage of the reflecting member (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-185921 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure has an object to suppress thermal shrinkage of a partition member in a surface light source having a partition member, and to provide a partition member used in the surface light source, and a liquid crystal display device using the surface light source. [Means for solving the problem]

[0005] A surface light source according to one embodiment of the present disclosure comprises a substrate, a plurality of light sources arranged on the substrate, and at least one partition member arranged on the substrate, the partition member including a plurality of first wall portions having a first ridge line extending in a first direction, a plurality of second wall portions having a second ridge line extending in a second direction intersecting the first direction, two opposing first wall portions and two opposing second wall portions, and a partition area surrounded by the first ridge lines and the second ridge lines in a planar view, the partition areas being arranged in the first direction and the second direction, with at least one first notch portion being provided on at least one of the first ridge lines, and the light sources being arranged within each of the partition areas. Effect of the Invention

[0006] According to an embodiment of the present disclosure, in a surface light source having a partition member, it is possible to suppress thermal shrinkage of the partition member. Also, it is possible to provide a partition member used in the surface light source, and a liquid crystal display device using the surface light source. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a plan view illustrating the partition member 1. [Diagram 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Diagram 3] FIG. 2 is a partial plan view of region A in FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Diagram 5] FIG. 11 is a cross-sectional view (part 1) showing another example of the continuous incision portion. [Figure 6] FIG. 11 is a cross-sectional view (part 2) showing another example of the continuous incision portion. [Figure 7] 10 is a diagram illustrating contraction due to a thermal load in a compartment member 1X according to a comparative example. FIG. [Figure 8] 1A to 1C are diagrams illustrating the suppression of shrinkage due to a thermal load in a partition member 1. [Figure 9] FIG. 2 is a partial plan view illustrating a partition member 1A. [Figure 10]FIG. 2 is a partial plan view illustrating a partition member 1B. [Figure 11] FIG. 2 is a partial plan view illustrating a partition member 1C. [Figure 12] FIG. 13 is a partial plan view illustrating a partition member 1D. [Figure 13] FIG. 2 is a partial plan view illustrating a partition member 1E. [Figure 14] FIG. 2 is a partial plan view illustrating a partition member 1F. [Figure 15] FIG. 2 is a plan view illustrating the surface light source according to the first embodiment. [Figure 16] 16 is a cross-sectional view taken along line XVI-XVI in FIG. 15. [Figure 17] FIG. 2 is a partial plan view (part 1) illustrating the partition member 2. [Figure 18] FIG. 2 is a second partial plan view illustrating the partition member 2. [Figure 19] FIG. 2 is a partial plan view (part 1) illustrating a partition member 2A. [Figure 20] FIG. 2 is a second partial plan view illustrating the partition member 2A. [Figure 21] FIG. 11 is a configuration diagram illustrating a liquid crystal display device according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, a description will be given of an embodiment of the invention with reference to the drawings. In the following description, terms indicating specific directions or positions (for example, "upper", "lower", and other terms including these terms) will be used as necessary. However, the use of these terms is for the purpose of facilitating understanding of the invention with reference to the drawings, and the meaning of these terms does not limit the technical scope of the present invention. In addition, parts with the same reference numerals appearing in multiple drawings indicate the same or equivalent parts or members.

[0009] Furthermore, the embodiments shown below are intended to exemplify surface light sources and the like for embodying the technical ideas of the present invention, and do not limit the present invention to the following. Furthermore, unless otherwise specified, the dimensions, materials, shapes, relative arrangements, etc. of the components described below are intended to be illustrative and not to limit the scope of the present invention. Furthermore, the contents described in one embodiment are also applicable to other embodiments and modified examples. Furthermore, the sizes and positional relationships of the members shown in the drawings may be exaggerated in order to clarify the explanation. Furthermore, in order to avoid the drawings becoming overly complicated, schematic diagrams that omit the illustration of some elements, or end views that show only the cut surfaces as cross-sectional views may be used.

[0010] First Embodiment In the first embodiment, first, the partition member will be described, and then the planar light source in which the partition member and the light source are arranged on a substrate will be described.

[0011] [Compartment member 1] Fig. 1 is a plan view illustrating the partition member 1. Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1.

[0012] As shown in Figs. 1 and 2, the partitioning member 1 has a plurality of first wall portions 10, a plurality of second wall portions 20, and a plurality of partition areas 30. The plurality of first wall portions 10 are arranged, for example, parallel to one another. The plurality of second wall portions 20 are arranged, for example, parallel to one another. The partitioning member 1 may have a plurality of bottom portions 40 as necessary. Hereinafter, a case in which the partitioning member 1 has a plurality of bottom portions 40 will be described as an example.

[0013] The first wall portion 10 has a first ridge line 11 extending in a first direction, a first side wall 12, and a second side wall 13. The first side wall 12 and the second side wall 13 are disposed on either side of the first ridge line 11 in a plan view. The upper end of the first side wall 12 and the upper end of the second side wall 13 are continuous. There is a space between the first side wall 12 and the second side wall 13.

[0014] The first ridge 11 is a line connecting the highest points of the first wall portion 10. The vicinity of the first ridge 11 may have a pointed shape or a rounded shape in a cross section cut in a direction perpendicular to the first ridge 11. The first ridge 11 may have a shape in which a very narrow flat portion extends linearly. The flat portion here is not wide enough to be used for screw fastening, but is narrower than the width of a screw hole. The width of this flat portion is, for example, 1 mm or less. The first ridge 11 does not have a wide portion that can be used for screw fastening, and has a substantially constant width.

[0015] The second wall portion 20 has a second ridge line 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 disposed on either side of the second ridge line 21 in a plan view. An upper end of the third side wall 22 and an upper end of the fourth side wall 23 are continuous with each other. There is a space between the third side wall 22 and the fourth side wall 23.

[0016] The second ridge 21 is a line connecting the highest points of the second wall portion 20. The vicinity of the second ridge 21 may have a pointed shape or a rounded shape in a cross section cut in a direction perpendicular to the second ridge 21. The second ridge 21 may have a shape in which a flat portion with a very narrow width extends linearly. The flat portion here is not wide enough to be used for screw fastening, but has a width narrower than that of a screw hole. The width of this flat portion is, for example, 1 mm or less. The second ridge 21 does not have a widened portion that can be used for screw fastening, and has a substantially constant width.

[0017] In FIG. 1, an X direction and a Y direction that are orthogonal to each other are defined, and a direction perpendicular to the X direction and the Y direction is defined as a Z direction. In the partitioning member 1, either of the directions in which the two ridgelines extend may be defined as a first direction. Here, the following description will be given with the X direction as the first direction X and the Y direction as the second direction Y, out of the orthogonal X direction and Y direction in FIG. 1. However, in the partitioning member 1, the first direction and the second direction do not have to be orthogonal to each other. In the following description, the -X direction of the target part may be 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.

[0018] The partitioned area 30 is an area surrounded by the first ridge line 11 and the second ridge line 21 in a plan view. A plurality of partitioned areas 30 are arranged in the first direction and the second direction. In the example of FIG. 1, a plurality of partitioned areas 30 are arranged in a matrix with the first direction X as the row direction and the second direction Y as the column direction. The number of partitioned areas 30 arranged in each row direction may be the same or different. Furthermore, the number of partitioned areas 30 arranged in each column direction may be the same or different. In the example of FIG. 1, a plurality of rectangular partitioned areas 30 are arranged in 4 rows and 8 columns in a plan view.

[0019] Each partitioned region 30 includes two opposing first walls 10, two opposing second walls 20, and a bottom 40. The bottom 40 is, for example, rectangular in plan view. In each partitioned region 30, the two opposing first walls 10 are a first side wall 12 located on the outer edge of the bottom 40 on the Y- side, and a second side wall 13 located on the outer edge of the bottom 40 on the Y+ side. In each partitioned region 30, the two opposing second walls 20 are a third side wall 22 located on the outer edge of the bottom 40 on the X- side, and a fourth side wall 23 located on the outer edge of the bottom 40 on the X+ side.

[0020] The outer edge of the bottom 40 is connected to the lower ends of the first side wall 12, the second side wall 13, the third side wall 22, and the fourth side wall 23. That is, the first side wall 12, the second side wall 13, the third side wall 22, and the fourth side wall 23 are arranged in a frame shape surrounding the bottom 40 in a plan view. The first side wall 12, the second side wall 13, the third side wall 22, and the fourth side wall 23 are inclined with respect to the bottom 40. In each partitioned region 30, the distance in the second direction Y between the region sandwiched between the opposing first side wall 12 and second side wall 13 is narrower toward the bottom 40 side and wider toward the upper part. In addition, in each partitioned region 30, the distance in the first direction X between the region sandwiched between the opposing third side wall 22 and fourth side wall 23 is narrower toward the bottom 40 side and wider toward the upper part.

[0021] The bottom 40 has an opening 40x. The opening 40x is an area in which a light source can be arranged when the partition member 1 is used as a surface light source. The opening 40x is arranged, for example, in the center of the bottom 40 and does not reach the lower ends of the first side wall 12, the second side wall 13, the third side wall 22, and the fourth side wall 23. In a plan view, the area of ​​the opening 40x is smaller than the area of ​​the bottom 40. The opening 40x is, for example, circular in a plan view.

[0022] In a vertical cross section taken through the center of the bottom 40 and parallel to the second direction Y, the first wall 10 including the first ridge 11, the first side wall 12, and the second side wall 13 preferably has a V-shape that opens downward. In a vertical cross section taken through the center of the bottom 40 and parallel to the first direction X (e.g., FIG. 2), the second wall 20 including the second ridge 21, the third side wall 22, and the fourth side wall 23 preferably has a V-shape that opens downward.

[0023] The first wall 10 located on the outer edge of the Y- side of the entire partitioning member 1 may not have the second side wall 13. In this case, the first ridge 11 located on the outer edge of the Y- side of the entire partitioning member 1 is the upper end of the first side wall 12. The second wall 20 located on the outer edge of the Y- side of the entire partitioning member 1 may or may not have the second notch 52. In addition, the first wall 10 located on the outer edge of the Y+ side of the entire partitioning member 1 may not have the first side wall 12. In this case, the first ridge 11 located on the outer edge of the Y+ side of the entire partitioning member 1 is the upper end of the second side wall 13. The second wall 20 located on the outer edge of the Y+ side of the entire partitioning member 1 may or may not have the second notch 52.

[0024] In addition, the second wall portion 20 located on the outer edge of the X- side of the entire partition member 1 may not have the fourth side wall 23. In this case, the second ridge line 21 located on the outer edge of the X- side of the entire partition member 1 is the upper end of the third side wall 22. The first wall portion 10 located on the outer edge of the X- side of the entire partition member 1 may or may not have the first notch 51. In addition, the second wall portion 20 located on the outer edge of the X+ side of the entire partition member 1 may not have the third side wall 22. In this case, the second ridge line 21 located on the outer edge of the X+ side of the entire partition member 1 is the upper end of the fourth side wall 23. The first wall portion 10 located on the outer edge of the X+ side of the entire partition member 1 may or may not have the first notch 51.

[0025] 3 is a partial plan view of region A in FIG. 1. The partition member 1 has a first cut portion 51 provided on the first ridge line 11 and a second cut portion 52 provided on the second ridge line 21. FIG. 3 illustrates a continuous cut portion 50 in which the first cut portion 51 and the second cut portion 52 are continuous. In the partition member 1 and the partition member 1A described later, the first cut portion 51 and the second cut portion 52 may be described in terms of the continuous cut portion 50. The first cut portion 51 is, for example, linear and extends in the first direction X, and the second cut portion 52 is, for example, linear and extends in the second direction Y. The lengths of the first cut portion 51 and the second cut portion 52 may be, for example, the same or different.

[0026] Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 3. As shown in Fig. 4, the continuous cut portion 50 may penetrate the first wall portion 10 or the second wall portion 20. Fig. 5 is a cross-sectional view (part 1) showing another example of the continuous cut portion. Fig. 6 is a cross-sectional view (part 2) showing another example of the continuous cut portion. Figs. 5 and 6 show a cross section corresponding to Fig. 4. As shown in Figs. 5 and 6, the continuous cut portion 50 does not have to penetrate the first wall portion 10 or the second wall portion 20.

[0027] That is, the first cut portion 51 may or may not penetrate the first wall portion 10. For example, the first cut portion 51 may be a recess with a bottom. When the first cut portion 51 does not penetrate the first wall portion 10, the depth of the first cut portion 51 is preferably half or more of the thickness of the first wall portion 10. When the first cut portion 51 does not penetrate the first wall portion 10, the first cut portion 51 may be disposed on the first ridge line 11 or may be disposed on the lower surface of the first wall portion 10 located immediately below the first ridge line 11. When the partition member 1 is used in a planar light source described later, if the first cut portion 51 is disposed on the lower surface of the first wall portion 10, optical effects such as uneven brightness can be suppressed.

[0028] In addition, the second cut portion 52 may or may not penetrate the second wall portion 20. For example, the second cut portion 52 may be a recessed portion with a bottom. When the second cut portion 52 does not penetrate the second wall portion 20, the depth of the second cut portion 52 is preferably half or more of the thickness of the second wall portion 20. When the second cut portion 52 does not penetrate the second wall portion 20, the second cut portion 52 may be disposed on the second ridge line 21 or may be disposed on the lower surface of the second wall portion 20 located immediately below the second ridge line 21. When the partition member 1 is used in a surface light source described later, if the second cut portion 52 is disposed on the lower surface of the second wall portion 20, optical effects such as uneven brightness can be suppressed.

[0029] In plan view, 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 between the first cut portion 51 and the second cut portion 52 coincides with the intersection point I. At least one continuous cut portion 50 may be provided. In the example of FIG. 3, the continuous cut portion 50 is disposed at all the intersection points I. Note that, in plan view, the shape of the continuous cut portion 50 provided at the intersection points I is not limited to a cross shape, and may be an L-shape, an I-shape, a T-shape, or the like.

[0030] The first cut portion 51 and the second cut portion 52 arranged at one intersection I are arranged away from other intersections I adjacent to that intersection I. When a continuous cut portion 50 is also provided at an adjacent intersection I, 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 shorter than the length of one side of the partitioned area 30, for example. The length of each of the first cut portion 51 and the second cut portion 52 can be, for example, one-third the length of one side of one partitioned area 30.

[0031] 3, the continuous cut portion 50 is drawn with an exaggerated thick line for the sake of convenience in order to clearly show the position of the continuous cut portion 50. However, in reality, the first cut portion 51 and the second cut portion 52 constituting the continuous cut portion 50 are formed to a width of, for example, several hundred μm by, for example, preparing a partition member intermediate body 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 making cuts therein using a blade such as a cutter.

[0032] The partition member 1 may also be formed by a method such as injection molding. When molding by injection molding, a mold is placed in the portions corresponding to the first cut portion 51 and the second cut portion 52 so that no member is formed in the portions corresponding to the first cut portion 51 and the second cut portion 52. In this way, the cut portion also includes the portion obtained without going through the step of "cutting".

[0033] The first cut portion 51 and the second cut portion 52 may be formed, for example, by preparing a partition member intermediate body 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 punching using a blade die. Specifically, for example, a blade die is placed on the lower surface side of the partition member intermediate body, and the partition member intermediate body is pressed from the upper surface side using a backing plate, so that the first cut portion 51 and the second cut portion 52 can be formed in the partition member intermediate body. This method is preferable in that burrs are unlikely to be generated when the first cut portion 51 and the second cut portion 52 are formed. In this case, the first cut portion 51 and the second cut portion 52 may be formed on the entire partition member intermediate body by punching once, or punching may be performed in multiple steps, or punching may be performed one place at a time.

[0034] At least a part of the first side wall 12 and the second side wall 13 may contact each other across the first cut portion 51. At least a part of the third side wall 22 and the fourth side wall 23 may contact each other across the second cut portion 52. In this way, by at least a part of the first cut portion 51 and / or the second cut portion 52 contacting each other, the partition member 1 has light reflectivity, and when used in a surface light source described later, it is possible to suppress light directly entering the first cut portion 51 and / or the second cut portion 52 from the light source and light returning from an optical sheet or the like from progressing into the first cut portion 51 and / or the second cut portion 52. This makes it possible to suppress a decrease in the amount of light extracted from the surface light source.

[0035] The partition member 1 can be disposed on a substrate and joined to the substrate to form a planar light source. When the partition member 1 has light reflectivity, the first side wall 12 and the second side wall 13 of the first wall portion 10, the third side wall 22 and the fourth side wall 23 of the second wall portion 20, and the bottom portion 40 function as reflective members that reflect light from a light source. In other words, the partition member 1 can be used as a reflector for a planar light source.

[0036] Note that "disposed on the substrate" includes both cases where the partitioning member, etc. is directly disposed on the upper surface of the substrate, and cases where the partitioning member, etc. is indirectly disposed via a covering member, etc., described below. Furthermore, "bonded to the substrate" includes both cases where the partitioning member, etc. is directly bonded to the upper surface of the substrate, and cases where the partitioning member, etc. is indirectly bonded to the substrate via a covering member, etc., described below.

[0037] In a planar light source in which the partitioning member 1 is disposed on a substrate and a light source is disposed on the substrate exposed in each opening 40x, when a thermal load is applied to the partitioning member 1, such as when the partitioning member 1 is stored in a high-temperature environment or when the light source is driven, the partitioning member 1 may shrink. Note that when stored in a high-temperature environment, thermal shrinkage may occur even in the partitioning member 1 alone.

[0038] For example, in the partitioning member 1X according to the comparative example shown in Fig. 7, no cuts are provided at all. When a thermal load is applied to the partitioning member 1X, the partitioning member 1X tries to shrink toward the center as indicated by the arrow. The larger the size of the partitioning member 1X is in a planar view, the greater the shrinkage of the partitioning member 1X. When the partitioning member 1X shrinks due to the thermal load, the distances from the light source to the first side wall 12, the second side wall 13, the third side wall 22, and the fourth side wall 23 in each partitioned region 30 may change.

[0039] On the other hand, in the partitioning member 1 provided with the continuous cut portion 50, the first ridge line 11 and the second ridge line 21 are divided by the continuous cut portion 50. Therefore, when a thermal load is applied, the partitioning member 1 can be shrunk for each of the first ridge line 11 and the second ridge line 21 divided by the continuous cut portion 50. By shrunk for each of the first ridge line 11 and the second ridge line 21, each of the first ridge line 11 and each of the second ridge lines 21 shrinks in the direction in which the first ridge line and the second ridge line themselves shrink (the direction of the arrow shown in FIG. 8), so that the partitioning member 1 can be prevented from shrinking to the center as shown in FIG. 7. This prevents the change in the distance from the light source to the first side wall 12, the second side wall 13, the third side wall 22, and the fourth side wall 23 in each partitioned region 30. As a result, the change in the reflection direction of light in the partitioning member 1 can be prevented, so that the luminance unevenness and chromaticity unevenness in the planar light source can be prevented.

[0040] The partition member 1 is formed into a shape having a first wall portion 10, a second wall portion 20, and a bottom portion 40, for example, by pressing a sheet of polyethylene terephthalate (PET) or the like having a thickness of about 0.2 to 0.3 mm with a mold. During forming, the intersection I is stretched the most, so the stress due to the thermal load is greatest at the intersection I. Therefore, providing the continuous cut portion 50 at the intersection I to relieve the stress is particularly effective in suppressing the shrinkage of the partition member 1 due to the thermal load. In addition, forming the continuous cut portion 50 in a cross shape is effective in suppressing the shrinkage of the partition member 1 in both the first direction X and the second direction Y. In addition, arranging the continuous cut portion 50 at all intersections I of the partition member 1 is effective in suppressing the shrinkage of the partition member 1 as a whole.

[0041] Furthermore, arranging the first cut portion 51 and the second cut portion 52 at the intersection I has the following advantage over arranging them at other points than the intersection I. That is, when the partitioning area 30 is rectangular, the intersection I is farther from the light source than the other points. For this reason, when the partitioning member is used as a planar light source, by providing the first cut portion 51 and the second cut portion 52 at a position farther from the light source, it is possible to make it difficult for light from the light source to hit the first cut portion 51 and the second cut portion 52, and optical effects such as uneven brightness can be suppressed.

[0042] Furthermore, in the partitioning member 1, each partitioned region 30 is rectangular in plan view and has the same shape, so that optical effects such as uneven brightness can be suppressed.

[0043] [Compartment member 1A] The partition member 1A is another example of the partition member. Fig. 9 is a partial plan view illustrating the partition member 1A. The partition member 1A differs from the partition member 1 (see Fig. 3, etc.) in that the continuous cut portions 50 are arranged in a staggered pattern.

[0044] Here, the staggered shape means that an intersection I where no continuous incision 50 is provided is present between adjacent continuous incision portions 50 in the first direction X, and an intersection I where no continuous incision 50 is provided is present between adjacent continuous incision portions 50 in the second direction Y. That is, in the partition member 1A, the continuous incision portions 50 are arranged on either side of the intersection I adjacent to the first direction X. Also, the continuous incision portions 50 are arranged on either side of the intersection I adjacent to the second direction Y. No continuous incision portions 50 are arranged at the intersection I where the continuous incision portions 50 are arranged, the intersection I adjacent to the first direction X, and the intersection I adjacent to the second direction Y.

[0045] The partitioning member 1A can be used as a reflector for a planar light source, similar to the partitioning member 1. Since the partitioning member 1A has the continuous cut portion 50, the same effect as the partitioning member 1 can be obtained.

[0046] [Compartment member 1B] The partition member 1B is another example of the partition member. Fig. 10 is a partial plan view illustrating the partition member 1B. The partition member 1B differs from the partition member 1 (see Fig. 3, etc.) in that the first cut portion 51 and the second cut portion 52 are not continuous with each other as in the continuous cut portion 50, but are spaced apart from each other.

[0047] In the compartment member 1B, the first cut portions 51 and the second cut portions 52 are alternately arranged at multiple intersection points I on the first ridge line 11 where the first ridge line 11 intersects with the second ridge line 21. Also, the first cut portions 51 and the second cut portions 52 are alternately arranged at multiple intersection points I on the second ridge line 21 where the first ridge line 11 intersects with the first ridge line 11. The first cut portions 51 and the second cut portions 52 may be alternately arranged only at either the multiple intersection points I on the first ridge line 11 where the first ridge line 11 intersects with the second ridge line 21 or the multiple intersection points I on the second ridge line 21 where the first ridge line 11 intersects with the first ridge line 11.

[0048] The first cut portion 51 arranged at one intersection I is arranged away from other intersections I adjacent to the intersection I. In other words, the first cut portion 51 arranged at one intersection I does not reach other intersections I adjacent to the intersection I. The same applies to the second cut portion 52.

[0049] The partitioning member 1B can be used as a reflector for a planar light source, similar to the partitioning member 1. The partitioning member 1B has the first cut portion 51 and the second cut portion 52, and therefore has the same effect as the partitioning member 1 in terms of suppressing shrinkage. In addition, in the continuous cut portion 50, the opening degree of the cut portion is relatively large near the intersection of the first cut portion 51 and the second cut portion 52, whereas when the first cut portion 51 and the second cut portion 52 are arranged apart from each other, the opening degree of the cut portion can be made small. Therefore, when the partitioning member 1B is used as a planar light source, the progression of the light emitted by the light source and the light returned from the optical sheet or the like to the first cut portion 51 and the second cut portion 52 is reduced, and the decrease in the amount of light extracted from the planar light source can be suppressed.

[0050] [Other variations of compartment components] In the partition 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 intersections I so as not to contact 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. The first cut portion 51 and the second cut portion 52 may also be configured by an arrangement of multiple points.

[0051] In addition, the shape of each partition area in the partition member is not limited to a rectangle in a plan view. For example, the shape of each partition area 30 may be a hexagon in a plan view, as in a partition member 1C shown in Fig. 11 and a partition member 1D shown in Fig. 12.

[0052] The partition members 1C and 1D have a plurality of third walls 70 in addition to a plurality of first walls 10 and a plurality of second walls 20. The third walls 70 are arranged, for example, parallel to each other. The partition members 1C and 1D may have a plurality of bottoms 40 as necessary.

[0053] The third wall portion 70 has a third ridge line 71 extending in a third direction different from the first direction and the second direction, a fifth side wall 72, and a sixth side wall 73. The fifth side wall 72 and the sixth side wall 73 are disposed on either side of the third ridge line 71 in a plan view. An upper end of the fifth side wall 72 and an upper end of the sixth side wall 73 are continuous with each other. There is a space between the fifth side wall 72 and the sixth side wall 73.

[0054] The third ridge line 71 is a line connecting the highest points of the third wall portion 70. The vicinity of the third ridge line 71 may have a pointed shape or a rounded shape in a cross section cut in a direction perpendicular to the third ridge line 71. As described for the first ridge line 11, the third ridge line 71 may have a shape in which a flat portion with a very narrow width extends linearly.

[0055] The partitioning members 1C and 1D have a first cut portion 51 provided on the first ridge line 11, a second cut portion 52 provided on the second ridge line 21, and a third cut portion 53 provided on the third ridge line 71. The first cut portion 51, the second cut portion 52, and the third cut portion 53 are continuous to form a continuous cut portion 50C. In the continuous cut portion 50C, the first cut portion 51, the second cut portion 52, and the third cut portion 53 are continuous at the intersection I of the first ridge line 11, the second ridge line 21, and the third ridge line 71. In the partitioning member 1C, the continuous cut portions 50C are arranged at all the intersection points I. In contrast, in the partitioning member 1D, the continuous cut portions 50C are arranged in a staggered pattern.

[0056] In this way, the partition members 1C and 1D have a plurality of first wall portions 10 having a first ridge line 11, a plurality of second wall portions 20 having a second ridge line 21, and a plurality of third wall portions 70 having a third ridge line 71 extending in a direction different from the first ridge line 11 and the second ridge line 21, and ends of the first ridge line 11, the second ridge line 21, and the third ridge line 71 are connected to define the partitioned regions 30. For example, if the partitioned regions 30 are hexagonal in plan view, the partitioned regions 30 are arranged in a honeycomb shape in plan view. The partitioned regions 30 may also be regular hexagonal in plan view.

[0057] FIG. 13 is a partial plan 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 FIG. 13, the partition member 1E may have a first outer circumferential cut portion 51E and a second outer circumferential cut portion 52E different from the first cut portion 51 and the second cut portion 52. The first outer circumferential cut portion 51E is a cut portion provided on the first ridge line 11 and located on the outer circumferential surface of the partition member 1E. The second outer circumferential cut portion 52E is a cut portion provided on the second ridge line 21 and located on the outer circumferential surface of the partition member 1E. The first outer circumferential cut portion 51E and the second outer circumferential cut portion 52E may be arranged perpendicular to the outer circumferential side of the partition member 1E.

[0058] In the partition member 1E, as an example, the first cut portions 51 and the second cut portions 52 are alternately arranged at a plurality of intersection points I where the first ridge line 11 intersects with the second ridge line 21. Also, as an example, the first cut portions 51 and the second cut portions 52 are alternately arranged at a plurality of intersection points I where the second ridge line 21 intersects with the first ridge line 11. The outer peripheral first cut portions 51E and the outer peripheral second cut portions 52E may be arranged according to these regularities, or may be arranged without following these regularities. In the example shown in FIG. 13, all the outer peripheral first cut portions 51E and the outer peripheral second cut portions 52E are arranged perpendicular to the sides of the periphery. In the example shown in FIG. 13, the length of the outer peripheral first cut portions 51E and the outer peripheral second cut portions 52E is shorter than the length of the first cut portions 51 and the second cut portions 52. The length of the outer peripheral first cut portion 51E and the outer peripheral second cut portion 52E may be, for example, about half the length of the first cut portion 51 and the second cut portion 52. The outer peripheral first cut portion 51E and the outer peripheral second cut portion 52E may be formed simultaneously with the first cut portion 51 and the second cut portion 52, or may be formed in a separate process from the first cut portion 51 and the second cut portion 52. By forming the outer peripheral first cut portion 51E, the outer peripheral second cut portion 52E, the first cut portion 51 and the second cut portion 52 simultaneously, productivity can be improved.

[0059] The partitioning member may be rectangular in plan view as shown in the example of FIG. 1, or may be irregular in plan view. FIG. 14 is a partial plan view illustrating a partitioning member 1F having an irregular shape in plan view, showing the lower left corner of the partitioning member 1F. Here, an irregular shape refers to a shape other than a rectangle in plan view, for example, a shape in which a complete rectangle is partially or entirely deformed to match a specific product shape. The outer periphery of the partitioning member may be composed of only a plurality of straight lines as shown in the example of FIG. 14, or may be composed of curved lines. In the partitioning member 1F, there is an area in the lower left corner where no partitioned area is arranged.

[0060] In the partitioning member 1F, as an example, the first cut portions 51 and the second cut portions 52 are alternately arranged at a plurality of intersection points I where the first ridge line 11 intersects with the second ridge line 21. Also, as an example, the first cut portions 51 and the second cut portions 52 are alternately arranged at a plurality of intersection points I where the second ridge line 21 intersects with the first ridge line 11. As in the partitioning member 1E, the outer peripheral first cut portions 51E and the outer peripheral second cut portions 52E may be arranged according to these regularities, or may be arranged without following these regularities. 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 perpendicular to the sides of the periphery.

[0061] Furthermore, the continuous cut portion passing through the intersection of the first ridge line 11 and the second ridge line 21 of the partition member may or may not be arranged along the first ridge line 11 and the second ridge line 21. When the continuous cut portion is not arranged along the first ridge line 11 and the second ridge line 21, the first cut portion 51 and the second cut portion 52 of the continuous cut are arranged on the side wall.

[0062] Furthermore, when the first cut portion 51 is disposed at the intersection of the first ridge line 11 and the second ridge line 21, the first cut portion 51 may extend, in a plan view, from the position of a line that passes through the lower end of the third side wall 22 and is parallel to the Y direction to the position of a line that passes through the lower end of the fourth side wall 23 and is parallel to the Y direction. Similarly, when the second cut portion 52 is disposed at the intersection of the first ridge line 11 and the second ridge line 21, the second cut portion 52 may extend, in a plan view, from the position of a line that passes through the lower end of the first side wall 12 and is parallel to the X direction to the position of a line that passes through the lower end of the second side wall 13 and is parallel to the X direction.

[0063] In addition, when a plurality of first cuts 51 are arranged on the first ridge 11, the length of each of the first cuts 51 may be the same, or the length of the cut may be longer for the first cuts 51 located closer to the outer periphery. Since the shrinkage of the partition member is greater on the outer periphery, the shrinkage on the outer periphery side can be suppressed by making the length of the cut longer for the first cuts 51 located closer to the outer periphery. The same applies when a plurality of second cuts 52 are arranged on the second ridge 21. That is, when a plurality of second cuts 52 are arranged on the second ridge 21, the length of each of the second cuts 52 may be the same, or the length of the cut may be longer for the second cuts 52 located closer to the outer periphery. In addition, when a plurality of first cuts 51 are arranged on the first ridge 11 and a plurality of second cuts 52 are arranged on the second ridge 21, the length of the cut may be longer for the first cuts 51 and second cuts 52 closer to the corners of the partition member. This can suppress shrinkage on the outer periphery side.

[0064] In addition, in the partition member, at least one first cut portion may be provided on at least one first ridge line, and no second cut portion may be provided on the second ridge line. In addition, in the partition member, at least one first cut portion may be provided on at least one first ridge line, and at least one second cut portion may be provided on at least one second ridge line.

[0065] [Surface light source 60] The above-mentioned partitioning members can be arranged on a substrate and joined to the substrate to form a surface light source. Here, the surface light source will be described using the partitioning member 1 as an example, but other partitioning members such as the above-mentioned partitioning members 1A and 1B may be used instead of the partitioning member 1. Also, a plurality of partitioning members may be arranged side by side on one substrate.

[0066] Fig. 15 is a plan view illustrating the surface light source according to the first embodiment. Fig. 16 is a cross-sectional view taken along line XVI-XVI in Fig. 15. As shown in Figs. 15 and 16, the surface light source 60 is a surface-emitting light-emitting device having a substrate 61, a covering member 62, a partitioning member 1, and a plurality of light sources 63. The partitioning 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 necessary.

[0067] In the surface light source 60, the lower surface of the bottom 40 of the partitioning member 1 is joined to a covering member 62 arranged on a substrate 61. That is, the lower surface of the bottom 40 of the partitioning member 1 is indirectly joined to the substrate 61 via the covering member 62. Also, in the surface light source 60, the light source 63 is arranged on the substrate 61 exposed within the opening 40x of the bottom 40. The members included in the surface light source 60 will be described in detail below.

[0068] (Substrate 61) The substrate 61 is a member for mounting a plurality of light sources 63. Conductor wirings 68A and 68B for supplying power to the light sources 63 are arranged on an upper surface 61m of the substrate 61. It is preferable that a covering member 62 covers a part of the regions of the conductor wirings 68A and 68B that are not electrically connected to the light emitting elements.

[0069] The material of the substrate 61 may be any material capable of insulating and isolating at least the pair of conductor wirings 68A and 68B, and examples of such materials include ceramics, resins, composite materials, etc. Examples of resins include phenolic resins, epoxy resins, polyimide resins, BT resins, polyphthalamide (PPA), polyethylene terephthalate (PET), etc. Examples of composite materials include the above-mentioned resins mixed with inorganic fillers such as glass fiber, SiO2, TiO2, and Al2O3, glass fiber reinforced resins (glass epoxy resins), and metal substrates in which a metal member is coated with an insulating layer.

[0070] The thickness of the substrate 61 can be appropriately selected. The substrate 61 may be either a flexible substrate or a rigid substrate that can be manufactured by a roll-to-roll method. The rigid substrate may be a thin rigid substrate that can be bent. The material of the conductor wirings 68A and 68B is not particularly limited as long as it is a conductive member, and a material that is usually used as a wiring layer of a circuit board or the like can be used. A light reflecting film or the like may be disposed on the surface of the conductor wirings 68A and 68B.

[0071] The covering member 62 is preferably made of an insulating material. Examples of the material of the covering member 62 include the same materials as those exemplified as the material of the substrate 61. By using the above-mentioned resin containing a white light-reflective filler or a large number of bubbles as the covering member 62, the light emitted from the light source 63 is reflected, and the light extraction efficiency of the surface light source 60 can be improved.

[0072] (Light source 63) The light source 63 is a member that emits light, and includes, for example, a light emitting element that emits light by itself, a light emitting element sealed with a light-transmitting resin, a surface-mounted light emitting device (also called an LED) in which a light emitting element is packaged, and the like. For example, as shown in FIG. 16, the light source 63 may be a light emitting element 63a covered with a sealing member 63b. The light source 63 may be a light emitting element 63 using one light emitting element 63a, or a plurality of light emitting elements may be used to form one light source 63. The light emitting element may be, for example, one that emits blue light. The light source 63 may also be configured to include a resin containing a light reflective material that surrounds the side surface of the light emitting element, and a light-transmitting member that covers the upper surface of the light emitting element and the upper surface of the resin containing the light reflective material. The light emitting element may also be configured to include a light-transmitting member that covers the upper surface of the light emitting element, and a resin containing a light reflective material that surrounds the side surface of the light emitting element and the side surface of the light emitting element and the light-transmitting member. The light-transmitting member here may include a phosphor. A light-transmitting adhesive member that bonds the light emitting element and the light-transmitting member may be provided between the light emitting element and the light-transmitting member.

[0073] The light sources 63 preferably have a wide light distribution so as to emit light with less uneven brightness in each partitioned region 30 of the partition member 1. In particular, it is preferable that each of the light sources 63 has a batwing light distribution characteristic. This reduces the amount of light emitted directly above the light sources 63, widening the light distribution of each light source 63, and irradiating the widened light onto the first side wall 12, the second side wall 13, the third side wall 22, the fourth side wall 23, and the bottom 40, thereby suppressing uneven brightness in each partitioned region 30.

[0074] Here, the batwing light distribution characteristic is defined as having an emission intensity distribution in which, with the optical axis OA being 0 degrees, the emission intensity is stronger at angles where the absolute value of the light distribution angle is greater than 0 degrees than at 0 degrees. Note that the optical axis OA is defined as a line that passes through the center of the light source 63 and perpendicularly intersects with the upper surface 61m of the substrate 61, as shown in Fig. 16.

[0075] In particular, as a light source 63 having batwing light distribution characteristics, for example, as shown in Fig. 16, a light emitting element 63a having a light reflecting film 63c on its upper surface is used. By providing the light reflecting film 63c on the upper surface of the light emitting element 63a, most of the light emitted upward from the light emitting element 63a is reflected by the light reflecting film 63c, suppressing the amount of light directly above the light emitting element 63a, thereby obtaining batwing light distribution characteristics. A lens may be separately combined to achieve batwing light distribution.

[0076] The light reflecting film 63c may be any of a metal film such as silver or copper, a resin containing a white filler, or a combination of these. The light reflecting film 63c may be a dielectric multilayer film (DBR film) having a reflectance angle dependency on the incident angle for the emission wavelength of the light emitting element 63a. Specifically, it is preferable to set the reflectance of the light reflecting film 63c so that it is lower for oblique incidence than for perpendicular incidence. This makes the change in luminance directly above the light emitting element 63a gentle, and makes it possible to prevent the area directly above the light emitting element 63a from becoming extremely dark, such as a dark spot.

[0077] The light source 63 may have a height of 100 μm to 500 μm for the light emitting element 63a directly mounted on the substrate 61. The light reflecting film 63c may have a thickness of 0.1 μm to 3.0 μm. The thickness of the light source 63 including the sealing member 63b may be about 0.5 mm to 2.0 mm.

[0078] The multiple light sources 63 can be driven independently of one another, and are preferably wired on the substrate 61 so that dimming control (for example, local dimming or high dynamic range) for each light source 63 is possible.

[0079] (Light emitting element 63a) Known light emitting elements 63a can be used. For example, it is preferable to use a light emitting diode as the light emitting element 63a. Any wavelength can be selected for the light emitting element 63a. For example, a nitride semiconductor such as GaN, InGaN, AlGaN, or AlInGaN can be used as a blue or green light emitting element. GaAlAs, AlInGaP, or the like can be used as a red light emitting element. Furthermore, semiconductor light emitting elements made of other materials may also be used. The composition, light emitting color, size, number, and the like of the light emitting element used can be appropriately selected according to the purpose.

[0080] 16, the light emitting element 63a may be flip-chip mounted via a bonding member 69 so as to straddle a pair of positive and negative conductor wirings 68A and 68B provided on the upper surface 61m of the substrate 61. However, the light emitting element 63a may be face-up mounted as well as flip-chip mounted.

[0081] The bonding member 69 is a member for bonding the light emitting element 63a to a substrate or a conductor wiring, and may be an insulating resin or a conductive member. In the case of flip chip mounting as shown in Fig. 16, a conductive member is used. Specifically, the bonding member may be an Au-containing alloy, an Ag-containing alloy, a Pd-containing alloy, an In-containing alloy, a Pb-Pd-containing alloy, an Au-Ga-containing alloy, an Au-Sn-containing alloy, an Sn-containing alloy, an Sn-Cu-containing alloy, an Sn-Cu-Ag-containing alloy, an Au-Ge-containing alloy, an Au-Si-containing alloy, an Al-containing alloy, a Cu-In-containing alloy, or a mixture of a metal and a flux.

[0082] (Sealing member 63b) The sealing member 63b covers the light emitting element 63a for the purpose of protecting the light emitting element 63a from the external environment and optically controlling the light emitted from the light emitting element 63a (for example, obtaining a bud wing light distribution characteristic). The sealing member 63b is made of a light-transmitting material. As the material of the sealing member 63b, a light-transmitting resin such as an epoxy resin, a silicone resin, or a resin mixture thereof, glass, etc. can be used. Among these, it is preferable to use a silicone resin in consideration of light resistance and ease of molding. The sealing member 63b may contain a diffusing agent for diffusing the light from the light emitting element 63a, a coloring agent corresponding to the light emission color of the light emitting element 63a, etc. As the diffusing agent, the coloring agent, etc., those known in the art can be used.

[0083] The sealing member 63b can be in direct contact with the substrate 61. The sealing member 63b is adjusted to a viscosity that allows printing, dispenser application, and the like, and can be cured by heating or light irradiation. Examples of the shape of the sealing member 63b include, but are not limited to, a substantially hemispherical shape, a vertically elongated convex shape in cross section, a flattened convex shape in cross section, a circular or elliptical shape in plan view, and the like. Here, the vertically elongated convex shape is a shape in which, in cross section, the maximum length in a direction perpendicular to the upper surface 61m of the substrate 61 is longer than the maximum length in a direction parallel to the upper surface 61m of the substrate 61. Also, the flattened convex shape is a shape in which, in cross section, the maximum length in a direction parallel to the upper surface 61m of the substrate 61 is longer than the maximum length in a direction perpendicular to the upper surface 61m of the substrate 61. The sealing member 63b may be disposed as an underfill 63d between the lower surface of the light emitting element 63a and the upper surface 61m of the substrate 61.

[0084] (Compartment member 1) The partition member 1 is disposed on a substrate 61. A space is provided between the lower surfaces of the first side wall 12 and the second side wall 13 and the upper surface of the substrate 61 or the upper surface of the covering member 62. A space is also provided between the lower surfaces of the third side wall 22 and the fourth side wall 23 and the upper surface of the substrate 61 or the upper surface of the covering member 62.

[0085] In the partitioning member 1, each opening 40x is disposed in the center of each partitioned region 30. The shape and size of each opening 40x may be any shape and size that exposes the entire light source 63, and it is preferable to set the outer edge of each opening 40x to be located only in the vicinity of the light source 63. This makes it possible to reflect light from the light source 63 also in each bottom 40 when the partitioning member 1 has light reflectivity, thereby improving the light extraction efficiency. In the partitioning member 1, each opening 40x may be formed before the formation of the first cut portion 51 and the second cut portion 52, may be formed after the formation of the first cut portion 51 and the second cut portion 52, or may be formed simultaneously with the first cut portion 51 and the second cut portion 52.

[0086] 16, the angle α formed by the adjacent third side wall 22 and fourth side wall 23 is preferably, for example, 60 degrees to 90 degrees. By setting the angle α in this range, the space and area occupied by the partition member 1 can be reduced, the height of the partition member 1 can be reduced, and the thickness of the planar light source 60 can be reduced. The same applies to the angle formed by the adjacent first side wall 12 and second side wall 13.

[0087] The pitch between adjacent first ridgelines 11 and the pitch between adjacent second ridgelines 21 can be appropriately adjusted depending on the size of the light source used, the size of the intended planar light source, etc. The pitch between adjacent first ridgelines 11 and the pitch between adjacent second ridgelines 21 can be, for example, 1 mm to 50 mm, preferably 5 mm to 20 mm, and more preferably 6 mm to 15 mm.

[0088] Furthermore, the height H of the partition member 1 itself, i.e., the length in the Z direction from the underside 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 in the case of a thinner surface light source, it is preferably approximately 1 mm to 4 mm.

[0089] The partition member 1 is preferably bonded to the substrate 61 using an adhesive member. This allows the partition member 1 to be suppressed from shrinking due to heat, since the partition member 1 is bonded to the substrate 61 via the adhesive member. The partition member 1 can be bonded around each opening 40x using a light-reflective adhesive member so that the light emitted from the light source 63 does not enter between the substrate 61 and the partition member 1. For example, it is more preferable to arrange a light-reflective adhesive member in a ring shape along the outer edge of each opening 40x. The adhesive member may be, for example, a double-sided tape having an acrylic resin-based adhesive on both sides of a PET base material, a hot-melt adhesive sheet, or a resin-based adhesive such as a thermosetting resin or a thermoplastic resin. These adhesive members preferably have high flame retardancy.

[0090] As described above, it is preferable that the partition member 1 has light reflectivity. This allows the light emitted from the light source 63 to be efficiently reflected upward by the first side wall 12, the second side wall 13, the third side wall 22, the fourth side wall 23, and the bottom 40.

[0091] The partition member 1 may be formed using a resin containing a reflecting material made of particles of titanium oxide, aluminum oxide, silicon oxide, or the like, or may be formed using a resin that does not contain a reflecting material, and then a reflecting material may be provided on the surface. Alternatively, a resin containing a plurality of fine bubbles may be used. In this case, light is reflected at the interface between the bubbles and the resin. Examples of the resin used for the partition member 1 include thermoplastic resins such as acrylic resin, polycarbonate resin, cyclic polyolefin resin, polyethylene terephthalate, polyethylene naphthalate, and polyester, and thermosetting resins such as epoxy resin and silicone resin. It is preferable that the partition member 1 is set so that the reflectance of the light emitted from the light source 63 is 70% or more.

[0092] The partition member 1 may be formed by a molding method using a mold, a molding method using photolithography, or the like, or the partition member 1 having the first wall portions 10, the second wall portions 20, and the bottom portions 40 may be prepared by purchasing. As a molding method using a mold, molding methods such as injection molding, extrusion molding, compression molding, vacuum molding, and press molding can be applied. For example, by vacuum molding using a reflective sheet made of PET or the like, a partition member 1 in which the first wall portions 10, the second wall portions 20, and the bottom portions 40 are integrally molded can be obtained.

[0093] The surface light source 60 may include a diffusion sheet as an optical member disposed above the light source 63 with the partition member 1 interposed therebetween. The surface light source 60 may include a diffusion sheet, which improves the uniformity of the light extracted from the surface light source 60 to the outside. The surface light source 60 may further include at least one selected from the group consisting of a wavelength conversion sheet, a first prism sheet, a second prism sheet, and a polarizing sheet above the diffusion sheet. The surface light source 60 may include at least one of these optical members, which further improves the uniformity of the light. The wavelength conversion sheet may, for example, absorb a part of the blue light from the light source, emit yellow light, green light, and / or red light, and emit white light. The wavelength conversion sheet is separated from the light emitting element 63a of the light source 63, and therefore may use a phosphor or the like that is poorly resistant to heat or light intensity and is difficult to use in the vicinity of the light emitting element 63a. This improves the performance of the surface light source 60 as a backlight. The phosphor contained in the wavelength conversion sheet is an yttrium-aluminum-garnet phosphor (e.g., Y3(Al,Ga)5O 12 :Ce), lutetium aluminum garnet phosphors (e.g., Lu3(Al,Ga)5O 12 :Ce), terbium aluminum garnet phosphors (e.g., Tb3(Al,Ga)5O 12 :Ce), CCA phosphors (e.g., Ca 10 (PO4)6C l2 :Eu), SAE phosphors (e.g., Sr4Al 14 O 25 :Eu), chlorosilicate phosphors (e.g., Ca8MgSi4O 16 Cl2:Eu), β-sialon phosphors (e.g., (Si,Al)3(O,N)4:Eu), α-sialon phosphors (e.g., Ca(Si,Al) 12 (O,N) 16 :Eu), SLA phosphors (e.g., SrLiAl3N4:Eu), CASN phosphors (e.g., CaAlSiN3:Eu) or SCASN phosphors (e.g., (Sr,Ca)AlSiN3:Eu), nitride phosphors such as KSF phosphors (e.g., K2SiF6:Mn), KSAF phosphors (e.g., K2(Si 0.99 ,Al0.01 )F 65.99 Examples of phosphors that can be used include fluoride phosphors such as 3.5MgO·0.5MgF2·GeO2:Mn) or MGF phosphors (for example, 3.5MgO·0.5MgF2·GeO2:Mn), phosphors having a perovskite structure (for example, CsPb(F,Cl,Br,I)3), and quantum dot phosphors (for example, CdSe, InP, AgInS2, or AgInSe2). When a phosphor is contained in the sealing member 63b, the above-mentioned materials can be used for this phosphor.

[0094] The surface light source 60 may be parallel to the XY plane, or curved toward the Z+ or Z- side with respect to the XY plane. For example, the surface light source 60 may be curved such that the center of the surface light source 60 is recessed toward the Z- side in the X direction.

[0095] Example First, a surface light source A having the same structure as the surface light source 60 shown in FIG. 15 was produced. For the surface light source A, a partitioning member was used that had the same rectangular outer shape as the partitioning member 1 shown in FIG. 1 and had the same cuts as the partitioning member 1B shown in FIG. 10. That is, a partitioning member was used in which the first cuts and the second cuts were alternately arranged at multiple intersections of the first ridge line and the second ridge line, and the first cuts and the second cuts were alternately arranged at multiple intersections of the second ridge line and the first ridge line. However, on the periphery of the partitioning member, a peripheral first cut and a peripheral second cut that are perpendicular to the side of the periphery were arranged. The length of the first cut and the second cut was about 3 mm, and the length of the peripheral first cut and the peripheral second cut was about 1.5 mm.

[0096] In addition, as a comparative example, a surface light source B was produced that had the same structure as the surface light source A, except that no cuts were provided in the partitioning member. The partitioning members of the surface light sources A and B were made of the same material. Polyethylene terephthalate (PET) was used as the material for the partitioning member.

[0097] For surface light source A and surface light source B, the dimensions of the partition members in the longitudinal direction (X direction) and transverse direction (Y direction) were measured as initial data, and both were X=225 mm and Y=127 mm.

[0098] Next, the surface light source A and the surface light source B were stored in an environment of 100° C., and the dimensions of the partition members in the X direction and the Y direction were measured after 1000 hours to examine the degree of shrinkage. The results are shown in Table 1.

[0099] [Table 1]

[0100] As shown in Table 1, in surface light source A, in which the partition member has a cut, the dimension of the partition member in the X direction shrank by 0.16 mm, and the dimension in the Y direction shrank by 0.12 mm. This is expressed as a shrinkage rate of 0.07% in the X direction and 0.26% in the Y direction. In contrast, in surface light source B, in which the partition member does not have a cut, the dimension of the partition member in the X direction shrank by 0.63 mm, and the dimension in the Y direction shrank by 0.42 mm. This is expressed as a shrinkage rate of 0.28% in the X direction and 0.92% in the Y direction.

[0101] In this way, it was confirmed that by providing cuts in the partition member, the shrinkage of the partition member in the X and Y directions in a high temperature environment can be suppressed to approximately 1 / 3 to 1 / 4 compared to when no cuts are provided in the partition member.

[0102] Second Embodiment In the second embodiment, an example of a compartment member having a structure in which two members are stacked will be described.

[0103] [Compartment member 2] Fig. 17 is a partial plan view (part 1) illustrating the partition member 2. Fig. 18 is a partial plan view (part 2) illustrating the partition member 2, showing the state before the two members are stacked. The partition member 2 shown in Fig. 17 is configured such that a lower member 1G is placed below the partition member 1A shown in Fig. 18.

[0104] That is, the partition member 2 has a partition member 1A and a lower member 1G that is disposed below the partition member 1A. In the partition member 2, the partition member 1A is disposed so as to overlap the lower member 1G. The overall shape of the partition member 1A is the same as the partition member 1 shown in Fig. 1 etc., and the positions and shapes of the cut portions are as described with reference to Fig. 9.

[0105] The lower member 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 member 1G has a plurality of bottom portions 140, and each bottom portion 140 is provided with an opening 140x. Note that the bottom portion and the opening portion may be provided by only one of the partition member 1A and the lower member 1G, or may be provided by both. In the case where the partition member 1A and the lower member 1G both have a bottom portion and an opening portion, when the partition member 1A is overlapped on the lower member 1G, the bottom portion 40 is disposed above the bottom portion 140, and the opening portion 40x and the opening portion 140x communicate with each other.

[0106] The fourth wall portion 110 has a fourth ridge line 111 extending in the 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 a line connecting the highest points of the fourth wall portion 110. The vicinity of the fourth ridge line 111 may have a pointed shape or a rounded shape in a cross section cut in a direction perpendicular to the fourth ridge line 111. As described for the first ridge line 11, the fourth ridge line 111 may have a shape in which a very narrow flat portion extends linearly.

[0108] Each of the fourth walls 110 is disposed below each of the first walls 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 a line connecting the highest points of the fifth wall portion 120. The vicinity of the fifth ridge line 121 may have a pointed shape or a rounded shape in a cross section cut in a direction perpendicular to the fifth ridge line 121. As described for the first ridge line 11, the fifth ridge line 121 may have a shape in which a very narrow flat portion extends linearly.

[0111] Each of the fifth walls 120 is disposed below each of the second walls 20 of the partition member 1A.

[0112] The lower member 1G has a lower continuous cut portion 150 in which a first lower cut portion 151 provided on the fifth ridge line 121 and a second lower cut portion 152 provided on the fourth ridge line 111 are continuous in a plan view. The first lower cut portion 151 is, for example, linear and extends in the second direction Y, and the second lower cut portion 152 is, for example, linear and extends in the first direction X. The lengths of the first lower cut portion 151 and the second lower cut portion 152 may be, for example, the same or different.

[0113] In plan view, the lower continuous cut portion 150 is cross-shaped.

[0114] In the partitioning member 1A, the continuous cuts 50 are arranged in a staggered pattern. In the lower member 1G, the lower continuous cuts 150 are also arranged in a staggered pattern and are positioned so as not to overlap the continuous cuts 50 of the partitioning member 1A in a plan view when the partitioning member 1A is overlapped on the lower member 1G.

[0115] The partitioning member 1A may or may not be bonded to the lower member 1G. When bonding the partitioning member 1A to the lower member 1G, an adhesive, double-sided tape, or the like may be used. For example, when both the partitioning member 1A and the lower member 1G have bottoms, the bottom 40 of the partitioning member 1A may be bonded to the bottom 140 of the lower member 1G. Alternatively, the wall portions of the partitioning member 1A and the lower member 1G may not be bonded to each other, but may be bonded to each other. Alternatively, the bottom portions of the partitioning member 1A and the lower member 1G may be bonded to each other, and the wall portions may then be bonded to each other.

[0116] The lower member 1G may be the same size as the partition member 1A, or may be a different size. For example, the lower member 1G may be sized so that the wall of the lower member 1G and the wall of the partition member 1A are in contact with each other, and the bottom of the lower member 1G and the bottom of the partition member 1A are in contact with each other. Similarly, the lower member 1H described later may be the same size as the partition member 1B, or may be a different size.

[0117] In this way, in the partitioning member 2, the continuous incision 50 and the lower continuous incision 150 are arranged at positions that do not overlap with each other in a planar view. Therefore, when the partitioning member 2 is used as a surface light source, the same effect as that of the partitioning member 1 can be obtained in terms of suppressing shrinkage of the partitioning member 2.

[0118] Furthermore, when the partitioning member 2 is used as a surface light source, light emitted by the light source or returned from an optical sheet or the like that passes through the cuts in the partitioning member 1A is reflected by the lower member 1G. Therefore, the decrease in the amount of light extracted from the surface light source can be suppressed compared to the case where the continuous cuts 50 are provided at all intersections I of the partitioning member 1 shown in FIG.

[0119] [Compartment member 2A] Fig. 19 is a partial plan view (part 1) illustrating a partition member 2A. Fig. 20 is a partial plan view (part 2) illustrating the partition member 2A, showing the state before the two members are stacked. The partition member 2A shown in Fig. 19 is obtained by placing a lower member 1H below the partition member 1B shown in Fig. 20. The partition member 2A shown in the example of Fig. 19 differs from the partition member 2 shown in Fig. 17 in the positional relationship of the cutout portions.

[0120] In the partition member 2A, the partition member 1B overlaps the lower member 1H, and in a plan view, the first cut portion 51 intersects with the first lower cut portion 151, and the second cut portion 52 intersects with the second lower cut portion 152. For example, in a plan view, the first cut portion 51 intersects with the first lower cut portion 151 in a cross shape, and the second cut portion 52 intersects with the second lower cut portion 152 in a cross shape.

[0121] In this way, in the partitioning member 2A, in a plan view, the first cut portion 51 intersects with the first lower cut portion 151, or the second cut portion 52 intersects with the second lower cut portion 152 at all intersection points I. Therefore, when the partitioning member 2A is used as a surface light source, the same effect as that of the partitioning member 1 can be obtained in terms of suppressing shrinkage of the partitioning member 2A.

[0122] Furthermore, when the partitioning member 2A is used as a planar light source, a portion of the light emitted by the light source and the light returned from the optical sheet or the like that passes through the cuts in the partitioning member 1B is reflected by the lower member 1H. Therefore, the reduction in the amount of light extracted from the planar light source can be suppressed compared to the case where the continuous cuts 50 are provided at all of the intersections I of the partitioning member 1 shown in Fig. 3. The effect of suppressing the reduction in the amount of light extracted is greater in the partitioning member 2 in which the continuous cuts 50 are completely blocked by the lower member 1G than in the partitioning member 2A.

[0123] [Variations of the second embodiment] In the partition member 2, at least one continuous cut portion 50 may be provided in the partition member 1A, and at least one lower continuous cut portion 150 may be provided in the lower member 1G at a position that does not overlap with the continuous cut portion 50 in a plan view.

[0124] Third embodiment In the third embodiment, an example of a liquid crystal display device (liquid crystal display device) using a surface light source 60 as a backlight light source is shown.

[0125] Fig. 21 is a configuration diagram illustrating a liquid crystal display device according to the third embodiment. As shown in Fig. 21, the liquid crystal display device 1000 includes, from the top, a liquid crystal panel 720, an optical sheet 710, and a surface light source 60. The surface light source 60 may include, as optical members above the light source 63, a DBEF (reflective polarizing sheet), a BEF (brightness enhancing sheet), a color filter, or the like.

[0126] The liquid crystal display device 1000 is a so-called direct type liquid crystal display device in which a surface light source 60 is laminated below a liquid crystal panel 720. The liquid crystal display device 1000 irradiates the liquid crystal panel 720 with light emitted from the surface light source 60.

[0127] From the viewpoint of making the surface light source thinner, the thickness of the surface light source can be set to 15 mm or less, which makes the surface light source thinner and allows the liquid crystal display device 1000 to be made thinner.

[0128] The surface light source 60 is not limited to being used as a backlight for the liquid crystal display device 1000. The surface light source 60 can also be used as a backlight for televisions, tablets, smartphones, smart watches, head-up displays, digital signage, bulletin boards, etc. The surface light source 60 can also be used as a light source for lighting, and can be used for emergency lighting, line lighting, various types of illumination, vehicle-mounted installations, etc.

[0129] The above describes the preferred embodiments, etc. However, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments, etc. without departing from the scope of the claims. [Explanation of symbols]

[0130] 1, 1A, 1B, 1C, 1D, 1E, 1F, 2, 2A Partition members 1G,1H Lower part 10 1st wall section 11 First Ridge 12 First side wall 13 Second side wall 20 Second wall section 21 Second Ridge 22 Third side wall 23 Fourth Side Wall 30 Plot Area 40,140 bottom 40x,140x opening 50,50C Continuous cut section 51 First notch 51E First outer notch 52 Second cut 52E Second outer periphery cut 53 Third cut 60 Planar light source 61 Substrate 61m top surface 62 Covering material 63 Light source 63a Light emitting element 63b Sealing member 63c light reflective film 63d Underfill 68A, 68B Conductor wiring 69 Joint materials 70 Third wall 71 The 3rd Ridge 72 5th side wall 73 6th Side Wall 110 4th wall 111 4th Ridge 112 7th Side Wall 113 8th Side Wall 120 5th wall 121 The 5th Ridge 122 9th Side Wall 123 10th Side Wall 150 Lower continuous cut 151 First lower notch 152 Second lower cutout 710 Optical Sheet 720 LCD Panel 1000 Liquid crystal display device

Claims

1. A substrate; A plurality of light sources disposed on the substrate; At least one partition member disposed on the substrate, The partition member is a plurality of first walls having first ridges extending in a first direction; a plurality of second wall portions each having a second ridge line extending in a second direction intersecting the first direction; a partitioned area including two of the first wall portions opposed to each other and two of the second wall portions opposed to each other, the partitioned area being surrounded by the first ridge line and the second ridge line in a plan view, The partitioned regions are arranged in a plurality of regions in the first direction and the second direction, At least one first cut portion is provided on at least one of the first ridge lines; the first wall portion has a first side wall and a second side wall disposed on either side of the first ridge line, At least a portion of the first side wall and the second side wall are in contact with each other across the first cut portion, The light sources are planar light sources arranged in the respective partitioned regions.

2. A surface light source as described in claim 1, wherein the first notches are arranged at multiple intersections where the first ridge line intersects with the second ridge line.

3. A surface light source as described in claim 1 or 2, wherein the first notches are arranged at multiple intersections where the second ridge line intersects with the first ridge line.

4. Further comprising a lower member disposed below the partition member, The lower member is a plurality of fourth wall portions each having a fourth ridge line extending in the first direction and disposed below each of the first wall portions; a plurality of fifth wall portions each having a fifth ridge line extending in the second direction and disposed below each of the second wall portions; The surface light source according to claim 2 , wherein a first lower cut portion is provided on the fifth ridge line so as to intersect with the first cut portion in a plan view.

5. A surface light source described in any one of claims 1 to 4, wherein the first cut-out portion is not positioned at an intersection, but is positioned between adjacent intersections so as not to contact the intersection.

6. A peripheral first cutout portion provided on the first ridge line and located on the outer periphery of the partition member. The surface light source according to claim 1 , further comprising:

7. A surface light source as described in Claim 6, wherein all of the peripheral first cut-out portions are arranged perpendicular to the peripheral edge of the partition member.

8. A surface light source as described in claim 6 or 7, wherein the length of the peripheral first cut portion is shorter than the length of the first cut portion.

9. A surface light source as described in claim 6 or 7, wherein the length of the peripheral first cut portion is half the length of the first cut portion.

10. A surface light source described in any one of claims 1 to 9, wherein the partition member has a rectangular shape when viewed in a plane.

11. A surface light source described in any one of claims 1 to 9, wherein the partition member has an irregular shape when viewed in a plane.

12. A surface light source described in any one of claims 1 to 11, wherein the length of the first cut portion is longer the closer the first cut portion is to the outer periphery.

13. A liquid crystal display device using a surface light source described in any one of claims 1 to 12 as a backlight light source.

14. A plurality of first wall portions having a first ridge line extending in a first direction; a plurality of second wall portions each having a second ridge line extending in a second direction intersecting the first direction; a partitioned area including two of the first wall portions opposed to each other and two of the second wall portions opposed to each other, the partitioned area being surrounded by the first ridge line and the second ridge line in a plan view, The partitioned regions are arranged in a plurality of regions in the first direction and the second direction, At least one first cut portion is provided on at least one of the first ridge lines; the first wall portion has a first side wall and a second side wall disposed on either side of the first ridge line, A partition member in which the first side wall and the second side wall are in contact with each other at least partially across the first cut portion.

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