Board and display device

Abstract

To provide a board and a display device capable of suppressing deviation of the board from a board pressing tool.SOLUTION: A light source board 20 is formed in a rectangular flat shape along mutually crossing X and Y directions while a light source for irradiating a display panel with light is mounted. The light source board 20 includes: a first surface roughness section 23a that extends along the X direction of the light source board 20 and is partially formed in each of two mutually opposing substrate side surfaces 21a, 21b; and a second surface roughness section 23b that is formed partially in each of the two surface side surfaces 21a, 21b and has larger surface roughness than the first surface roughness section 23a. The first surface roughness section 23a and the second surface roughness section 23b are lined up alternately in the X direction. The second surface roughness section 23b of each of the two substrate side surfaces 21a, 21b is formed at a position not opposing the Y direction.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a substrate and a display device. [Background technology]

[0002] The metal mask plate for printing solder paste described in Patent Document 1 prints solder paste onto pads formed on a printed circuit board. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2006-100638 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the configuration described in Patent Document 1, when printing the cream solder, the printed circuit board is held down by a board holding jig, but there is a risk that this holding force will cause the printed circuit board to come off the board holding jig.

[0005] The present disclosure has been made in consideration of the above-described circumstances, and aims to provide a substrate and a display device that can prevent the substrate from coming off a substrate holding jig. [Means for solving the problem]

[0006] In order to achieve the above object, a substrate according to a first aspect of the present disclosure comprises: A substrate on which a light source for illuminating a display is mounted and which is formed in a rectangular flat plate shape along a first direction and a second direction perpendicular to each other, a first surface roughness portion extending along the first direction of the substrate and partially formed on each of two opposing side surfaces; a second surface roughness portion partially formed on each of the two side surfaces and having a surface roughness greater than that of the first surface roughness portion; the first surface roughness portions and the second surface roughness portions are alternately arranged in the first direction, The second surface roughness portions of the two side surfaces are formed at positions not facing each other in the second direction.

[0007] In order to achieve the above object, a substrate according to a second aspect of the present disclosure comprises: A substrate on which a light source for illuminating a display is mounted and which is formed in a rectangular flat plate shape along a first direction and a second direction perpendicular to each other, a plurality of protrusions extending along the first direction of the substrate and partially formed on each of two opposing side surfaces; The plurality of protruding portions are arranged with gaps in the first direction, The protrusions on the two side surfaces are formed at positions that do not face each other in the second direction.

[0008] In order to achieve the above object, a substrate according to a third aspect of the present disclosure comprises: A substrate that is a raw material for manufacturing a light source substrate on which a light source for illuminating a display is mounted, and is formed in a rectangular flat plate shape along a first direction and a second direction perpendicular to each other, a first area in which the light source can be mounted; a second region surrounding the first region; a plurality of connection portions connecting the first region and the second region; The plurality of connection portions are arranged with gaps therebetween in the first direction and are formed at positions not facing each other in the second direction.

[0009] In order to achieve the above object, a display device according to a fourth aspect of the present disclosure comprises: The substrate; A plurality of light sources mounted on the substrate; a substrate holder that holds the substrate in a curved state with a radius of curvature of 10,000 mm or less; The display has a curved plate shape that curves along the substrate. Effect of the Invention

[0010] According to the present disclosure, it is possible to prevent the substrate from coming off the substrate holding jig. [Brief description of the drawings]

[0011] [Figure 1] 1 is a perspective view of a display device according to a first embodiment of the present disclosure. [Diagram 2] 2 is a perspective view of a light source substrate held by a substrate holding portion according to the first embodiment of the present disclosure. FIG. [Diagram 3] FIG. 2 is a schematic cross-sectional view taken along line III-III in FIG. [Figure 4] 4 is a plan view of the light source substrate when not held by the substrate holding portion according to the first embodiment of the present disclosure. FIG. [Diagram 5] FIG. 2 is a plan view of a blank substrate according to the first embodiment of the present disclosure. [Figure 6] FIG. 11 is a plan view of a blank substrate according to a comparative example. [Figure 7A] FIG. 2 is a schematic diagram of a blank substrate during chucking according to the first embodiment of the present disclosure. [Figure 7B] 5A to 5C are schematic diagrams of a blank substrate when an upper surface pressing portion is retracted according to the first embodiment of the present disclosure and the comparative example. [Figure 8] FIG. 13 is a diagram showing stress distribution in a blank substrate according to a comparative example. [Figure 9] FIG. 4 is a diagram showing stress distribution in the blank substrate according to the first embodiment of the present disclosure. [Figure 10] FIG. 11 is a plan view of a blank substrate according to a second embodiment of the present disclosure. [Figure 11] FIG. 11 is a diagram showing stress distribution in a blank substrate according to a second embodiment of the present disclosure. [Figure 12] FIG. 11 is a plan view of a blank substrate according to a third embodiment of the present disclosure. [Figure 13] FIG. 13 is a diagram showing stress distribution in a blank substrate according to a third embodiment of the present disclosure. [Figure 14] FIG. 11 is a plan view of a light source substrate when not held by a substrate holding portion according to a third embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] (First embodiment) A substrate and a display device according to a first embodiment of the present disclosure will be described with reference to the drawings. The display device is an on-board meter mounted on a vehicle. 1, the display device 10 has a display surface 11 that displays vehicle information. The display surface 11 has a rectangular shape that is long in the left-right direction (X direction). In this example, the display surface 11 is curved in a concave shape in the X direction when viewed by a viewer. In the following description, the longitudinal direction (left-right direction) of the display surface 11 is defined as the X direction, and the lateral direction (height direction) of the display surface 11 is defined as the Y direction.

[0013] As shown in FIG. 3, the display device 10 includes a case 15, a board holder 16, a light source board 20, a plurality of light sources 30, and a display panel 50. The light source board 20 includes a light source 30 and a display panel 50. The light source 30 is a light source. The case 15 is a hollow rectangular parallelepiped. The case 15 accommodates a board holder 16, a light source board 20 on which a plurality of light sources 30 are mounted, and a display panel 50. The case 15 includes a case body 15b made of a light-shielding resin and opening toward the front (viewer's side), and a cover light-transmitting plate material 15a that closes the opening of the case body 15b.

[0014] The multiple light sources 30 are each composed of an LED (Light Emitting Diode) and are arranged in a matrix on the mounting surface (front surface) of the light source substrate 20. The multiple light sources 30 emit illumination light to the rear surface of the display panel 50. The multiple light sources 30 are each mounted on the mounting surface of the light source substrate 20 via a solder section 17. The specific configuration of the light source substrate 20 will be described later.

[0015] The display panel 50 is a TFT (Thin Film Transistor) type liquid crystal panel. The display panel 50 has a rectangular shape that is long in the X direction along the display surface 11 and curved concavely in the X direction.

[0016] 2, the substrate holding portion 16 holds the back surface side of the light source substrate 20. The substrate holding portion 16 holds the flexible light source substrate 20 in a curved state. In this embodiment, the substrate holder 16 is configured as a separate body from the case 15 , but the present invention is not limited to this and may be configured as a part of the case 15 .

[0017] The light source substrate 20 is a rectangular plate that is long in the X direction. The light source substrate 20 is a flexible printed circuit board. The light source substrate 20 is made by permeating epoxy resin into a woven glass fabric made by weaving glass fibers into a cloth-like material. The thickness of the light source substrate 20 is set to be 0.15 mm or more and 0.5 mm or less. The light source substrate 20 is held in a concavely curved state in the X direction as seen by a viewer by the substrate holding portion 16. The radius of curvature of the light source substrate 20 held in this curved state is set to 10000 mm or less, for example, in the range of 1000 mm to 5000 mm, and preferably 2900 mm.

[0018] As shown in Fig. 4, the light source substrate 20 having a rectangular plate shape has four substrate side surfaces 21a to 21d. Note that the light sources 30 and the solder parts 17 are omitted from Fig. 4. The substrate side surfaces 21a and 21b extend parallel to the X-direction. The substrate side surface 21a is an upper side surface of the light source substrate 20, and the substrate side surface 21b is a lower side surface of the light source substrate 20. The substrate side surfaces 21c and 21d extend parallel to the Y direction. The substrate side surface 21c is the left side surface of the light source substrate 20, and the substrate side surface 21d is the right side surface of the light source substrate 20.

[0019] The light source substrate 20 includes a plurality of protruding portions 22a to 22f formed on the substrate side surfaces 21a to 21d. The plurality of protruding portions 22a to 22f are substantially in the shape of a base plate (see the enlarged view of the upper portion of FIG. 4) whose bottom surfaces are connected to the substrate side surfaces 21a to 21d. The thickness of each of the protruding portions 22a to 22f is the same as the thickness of the light source substrate 20 other than the protruding portions 22a to 22f. The plurality of protruding portions 22a to 22f form unevenness on the substrate side surfaces 21a to 21d, and the unevenness is formed with a height difference (for example, 0.1 mm to 3 mm) that can be felt when a human finger is traced on the substrate side surfaces 21a to 21d. The plurality of protruding portions 22a to 22f are the remaining portions of the connection portions 43a to 43d (see FIG. 5) of the blank substrate 40 described later.

[0020] The multiple protrusions 22a, 22e are arranged on the substrate side surface 21a with a gap therebetween in the X direction. The two protrusions 22e are arranged at both ends of the substrate side surface 21a in the X direction, one at each end. The multiple (five in this example) protrusions 22a are arranged at a fixed gap P between the two protrusions 22e.

[0021] The multiple protrusions 22b, 22f are arranged on the substrate side surface 21b with a gap therebetween in the X direction. The two protrusions 22f are arranged at both ends of the substrate side surface 21b in the X direction, one at each end. The multiple (five in this example) protrusions 22b are arranged at a fixed gap P between the two protrusions 22f.

[0022] The multiple protrusions 22a and the multiple protrusions 22b are arranged at the same interval P, but are offset in the X direction so as not to face each other in the Y direction. The intermediate positions of the multiple protrusions 22a (the positions of the lines that bisect the interval P) are located on the multiple protrusions 22b, and the intermediate positions of the multiple protrusions 22b are located on the multiple protrusions 22a. The protrusions 22e and 22f located at both ends of the substrate side surfaces 21a and 21b in the X direction are positioned to face each other in the Y direction.

[0023] The multiple protrusions 22c are arranged on the substrate side surface 21c at intervals in the Y direction. The multiple protrusions 22d are arranged on the substrate side surface 21d at intervals in the Y direction. The multiple protrusions 22c and the multiple protrusions 22d are positioned to face each other in the X direction.

[0024] As shown enlarged in the upper part of FIG. 4, the substrate side surfaces 21a to 21d include a first surface roughness portion 23a and a second surface roughness portion 23b. The first surface roughness portion 23a and the second surface roughness portion 23b are alternately formed in the direction in which the substrate side surfaces 21a to 21d extend. The length of each of the first surface roughness portions 23a is longer than the length of each of the second surface roughness portions 23b, for example, 5 to 10 times (about 7 times in this example) longer. The second surface roughness portion 23b is formed on the outer side surface of each of the convex portions 22a to 22f (the upper surface of the convex portion 22a in the case of the convex portion 22a). The first surface roughness portion 23a is a region between each of the convex portions 22a to 22f on the substrate side surfaces 21a to 21d. The second surface roughness portion 23b is formed as a surface having a rougher surface roughness than the first surface roughness portion 23a. The difference in surface roughness between the first surface roughness portion 23a and the second surface roughness portion 23b arises due to differences in processing methods, and is set to a level that allows a user to feel that the second surface roughness portion 23b is rougher than the first surface roughness portion 23a by running their finger over it (for example, a difference in arithmetic mean surface roughness of about 0.1 μm to several tens of μm).

[0025] A resist layer (not shown) is formed on the entire outer surface of the light source substrate 20 except for the second rough surface portion 23b. In the second rough surface portion 23b, the base material of the light source substrate 20 is exposed. Therefore, among the substrate side surfaces 21a to 21d, the first rough surface portion 23a is a region where a resist layer is formed, and the second rough surface portion 23b is a region where a resist layer is not formed. Since the resist layer is green, it is possible to visually distinguish whether it is the first rough surface portion 23a or the second rough surface portion 23b depending on whether it is a green region or not.

[0026] Next, a method for manufacturing the light source substrate 20 will be described. First, a blank substrate 40 that serves as a raw material for the light source substrate 20 is prepared.

[0027] The configuration of the blank substrate 40 will be described. 5, the blank substrate 40 includes a first region 41, a second region 42, connection portions 43a to 43f, and long holes 44a to 44d. The long holes 44a to 44d are formed by a hole-making tool such as a router or a drill. The surface roughness of the first rough surface portion 23a is determined by the surface roughness of the machined surface resulting from the hole-making process using the hole-making tool. The first region 41 is a region where a light source is mounted, and is a region that becomes the light source substrate 20 through a cutting process described later. The second region 42 has a rectangular frame shape surrounding the periphery of the first region 41. The second region 42 is an area that is discarded after the first region 41 is cut out.

[0028] The connection portions 43a to 43f connect the first region 41 and the second region 42. The connection portions 43a are arranged at intervals in the X direction in a gap between the upper side portion of the first region 41 and the second region 42. The connection portions 43a, 43e are arranged corresponding to the protrusions 22a, 22e (see FIG. 4). The long holes 44a are formed long in the X direction and are arranged in a row in the X direction. The connection portions 43a are formed between the long holes 44a. The surface of the long holes 44a on the first region 41 side is the first surface roughness portion 23a (see FIG. 4) of the light source substrate 20.

[0029] The multiple connection portions 43b, 43f are arranged at intervals in the X direction in the gap between the lower side portion of the first region 41 and the second region 42. The multiple connection portions 43b, 43f are arranged corresponding to the protrusions 22b, 22f (see FIG. 4). The multiple long holes 44b are formed long in the X direction and are arranged in a row in the X direction. The connection portions 43b are formed between the multiple long holes 44b. The surface of the long holes 44b on the first region 41 side is the first surface roughness portion 23a (see FIG. 4) of the light source substrate 20.

[0030] The interval Q between connection portion 43e located at the upper left corner of blank substrate 40 and its adjacent connection portion 43a is narrower than the interval P between the multiple connection portions 43a, and the interval Q between connection portion 43f located at the lower right corner of blank substrate 40 and its adjacent connection portion 43b is narrower than the interval P between the multiple connection portions 43b. In this manner, by shortening the interval Q between connection portions 43e and 43a and the interval Q between connection portions 43f and 43b near the two diagonally opposite corners of blank substrate 40, thermal deformation of blank substrate 40 (particularly, first region 41) is suppressed when blank substrate 40 is heated in a furnace.

[0031] The multiple connection parts 43c, 43d are arranged at intervals in the Y direction in the gap between the left and right sides of the first region 41 and the second region 42. The multiple connection parts 43c, 43d are arranged corresponding to the protrusions 22c, 22d (see FIG. 4). The long holes 44c, 44d are formed long in the Y direction and are arranged in a row in the Y direction. The connection parts 43c, 43d are formed between the multiple long holes 44c, 44d. The surfaces of the long holes 44c, 44d on the first region 41 side are the first surface roughness portion 23a (see FIG. 4) of the light source substrate 20.

[0032] The width (length in the short direction) of the long holes 44a to 44d is set to 1 mm to 3 mm, for example, 2 mm. The length of the long holes 44a, 44b (excluding the long hole 44a1 at the upper left corner and the long hole 44b1 at the lower right corner of the blank substrate 40) is set to 30 mm to 40 mm, for example, about 35 mm. The length of the long holes 44c, 44d (excluding the long holes 44c, 44d located at the uppermost and lowermost positions among the multiple long holes 44c, 44d) is set to 4 mm to 14 mm, for example, about 9 mm. The length of the connection parts 43a to 43d is set depending on the interval between the long holes 44a to 44d. The length of the connection parts 43a to 43d is set to 3 mm to 8 mm, for example, about 5 mm. This concludes the description of the configuration of the blank substrate 40.

[0033] Next, a metal plate is printed to be soldered onto the blank substrate 40 . 7A, blank substrate 40 is chucked by substrate holding jig 60. Substrate holding jig 60 includes a lower surface support portion 61, a side surface holding portion 62, and an upper surface holding portion 63. The blank board 40 is placed on the lower surface support portion 61 so as to come into contact with the lower surface of the blank board 40. The side surface pressing portion 62 is configured to be slidable in a direction along the blank board 40, and holds the blank board 40 from the Y direction (board short side direction) by pressing two side surfaces extending in the X direction of the placed blank board 40. The upper surface pressing portion 63 is configured to be slidable in a direction along the blank board 40, and presses the blank board 40 from above by coming into contact with the upper surface of the placed blank board 40.

[0034] The blank board 40 is placed on the bottom support portion 61, the side surfaces of the blank board 40 are pressed from the Y direction by the side surface pressing portion 62, and the top surface of the blank board 40 is pressed by the top surface pressing portion 63, and then the top surface pressing portion 63 is retracted from the blank board 40 as shown in FIG. 7B. Then, with cream solder 17a attached to the bottom surface of the metal mask 70, the bottom surface of the metal mask 70 is pressed against the top surface of the blank board 40. This causes the cream solder 17a to adhere to the top surface of the blank board 40. This completes the metal plate printing. Next, after the light source is placed on the cream solder 17a, the blank substrate 40 is placed in a furnace and the entire substrate is heated, whereby the cream solder 17a melts and the electrode terminals of the light source are joined to the cream solder 17a.

[0035] Then, in order to cut out the first region 41 from the blank substrate 40, the blank substrate 40 is cut along the cut line CL with a cutting tool such as a foil cutter. The surface roughness of the second rough surface portion 23b is determined by the surface roughness of the cut surface processed with this cutting tool. The cut line CL passes through the portions of the connecting portions 43a to 43d on the first region 41 side. This completes the light source substrate 20. The second region 42 of the blank substrate 40 becomes a remaining material.

[0036] Next, the action of the blank substrate 40 when the blank substrate 40 is chucked by the substrate holding jig 60 will be described while comparing with a comparative example. As shown in Fig. 6, in blank substrate 140 according to the comparative example, connection portions 143a, 143b are disposed at positions facing each other in the Y direction. This point differs from the configuration of blank substrate 40 according to the present embodiment shown in Fig. 5.

[0037] As shown in Fig. 7B, when the blank substrate 140 according to the comparative example is chucked by the substrate holding jig 60 and the top surface holding portion 63 is retracted from the top surface of the blank substrate 40, the end of the blank substrate 140 comes off the side surface holding portion 62, as shown by the dashed line in Fig. 7B. Therefore, metal plate printing cannot be performed normally. On the other hand, in the case of the blank substrate 40 according to this embodiment, at this time, as shown in Fig. 7A, the end portion of the blank substrate 40 does not come off the side pressing portion 62. Therefore, metal plate printing can be performed normally.

[0038] Next, the principle by which the end of the blank substrate 140 in the comparative example comes off the side surface pressing portion 62 and the end of the blank substrate 40 in this embodiment does not come off the side surface pressing portion 62 will be described. Fig. 8 shows a simulation result of stress distribution when a compressive force or a tensile force is applied in the Y direction of the blank board 140 according to the comparative example. Fig. 9 shows a simulation result of stress distribution when a compressive force or a tensile force is applied in the Y direction of the blank board 40 according to the present embodiment. In this simulation, it is assumed that the blank boards 40, 140 are sandwiched between the side pressing parts 62 from the short side direction, and the stress generated in the blank boards 40, 140 when a load of 10 N / n is applied to both ends of the blank boards 40, 140 in the Y direction is calculated and shown as stress distribution. From these simulation results, it can be seen that stress is concentrated at each of the connection parts 43a, 43b, 143a, and 143b of the blank boards 40 and 140. Comparing Fig. 8 and Fig. 9, the blank board 40 according to this embodiment has a higher degree of stress concentration at the connection parts 43a and 43b than the blank board 140 according to the comparative example. In this way, by concentrating stress at the end part in the Y direction of the blank board 40, the end part in the Y direction of the blank board 40 can be actively bent when chucked by the side pressing part 62, and the amount of deflection of the blank board 40 in the entire area in the Y direction can be reduced. Therefore, the end part of the blank board 40 is less likely to come off the side pressing part 62. On the other hand, in the blank substrate 140 according to the comparative example, the degree of stress concentration at the connection portions 143a, 143b is low, and therefore the stress between the two connection portions 143a, 143b arranged in the Y direction is large. Therefore, the amount of deflection of the blank substrate 140 in the entire Y direction is large when chucked by the side surface pressing portion 62. Therefore, the end portion of the blank substrate 140 is easily released from the side surface pressing portion 62.

[0039] (effect) According to the first embodiment described above, the following effects are achieved. (1) A blank substrate 40, which is an example of a substrate, is mounted with a light source 30 that illuminates a display panel 50, serves as a raw material for manufacturing a light source substrate 20, and is formed in a rectangular flat plate shape along an X direction (first direction) and a Y direction (second direction) that are perpendicular to each other. The blank substrate 40 includes a first region 41 in which the light source 30 can be mounted, a second region 42 that surrounds the periphery of the first region 41, and a plurality of connecting portions 43a, 43b that connect the first region 41 and the second region 42. The plurality of connecting portions 43a, 43b are arranged with gaps in the X direction. The plurality of connecting portions 43a, 43b are formed in positions that do not face each other in the Y direction. With this configuration, as described above, when the blank substrate 40 is chucked during processing (e.g., during metal plate printing) of the blank substrate 40, it is possible to prevent the end of the blank substrate 40 from coming off the side holding portion 62.

[0040] (2) The light source substrate 20, which is an example of a substrate, is mounted with a light source 30 for illuminating a display panel 50, which is an example of a display device, and is formed in a rectangular flat plate shape along the X direction and the Y direction perpendicular to each other. The light source substrate 20 extends along the X direction of the light source substrate 20 and includes a first surface roughness portion 23a partially formed on each of two substrate side surfaces 21a, 21b facing each other, and a second surface roughness portion 23b partially formed on each of the two substrate side surfaces 21a, 21b and having a surface roughness greater than that of the first surface roughness portion 23a. The first surface roughness portion 23a and the second surface roughness portion 23b are alternately arranged in the X direction. The second surface roughness portions 23b on the two substrate side surfaces 21a, 21b are formed at positions that do not face each other in the Y direction. According to this configuration, as described above, it is possible to prevent the end portion of the blank substrate 40, which is the raw material for the light source substrate 20 having the rough surface portions 23a and 23b, from coming off the side surface pressing portion 62.

[0041] (3) The light source substrate 20 is mounted with the light source 30 that illuminates the display panel 50, and is formed in a rectangular flat plate shape along the X direction and Y direction that are perpendicular to each other. The light source substrate 20 extends along the X direction of the light source substrate 20, and includes a plurality of protrusions 22a, 22b partially formed on each of two substrate side surfaces 21a, 21b that face each other. The plurality of protrusions 22a, 22b are arranged with gaps in the X direction. The protrusions 22a, 22b on each of the two side surfaces are formed in positions that do not face each other in the Y direction. According to this configuration, as described above, it is possible to prevent the end portion of the blank substrate 40, which is the raw material for the light source substrate 20 having the protrusions 22a and 22b, from coming off the side surface pressing portion 62.

[0042] (4) The thickness of the light source substrate 20 or the blank substrate 40 is 0.5 mm or less. When the blank substrate 40 is thin, the blank substrate 40 is likely to bend due to chucking by the substrate holding jig 60; however, by adjusting the position of the connection portions 43a, 43b, the overall amount of bending of the blank substrate 40 can be reduced, thereby preventing the ends of the blank substrate 40 from coming off the side holding portions 62.

[0043] (5) The display device 10 includes a light source substrate 20, a plurality of light sources 30 mounted on the light source substrate 20, a substrate holding portion 16 that holds the light source substrate 20 in a curved state with a radius of curvature of 10,000 mm or less, and a curved plate-like display panel 50 that curves along the light source substrate 20. According to this configuration, even if the light source substrate 20 is formed thin and bendable as described above, the ends of the blank substrate 40 that is the raw material for the light source substrate 20 can be prevented from coming off the side pressing portions 62.

[0044] Second embodiment A substrate and a display device according to a second embodiment of the present disclosure will be described with reference to the drawings. This embodiment differs from the first embodiment in that slit holes are formed in the second region of the blank substrate. The following description will focus on the differences from the first embodiment.

[0045] As shown in FIG. 10, a blank substrate 240 includes a first region 41, a second region 42, connection portions 43a to 43f, and long holes 44a to 44d, as well as a plurality of slit holes 45a and 45b. The slit holes 45a, 45b are each formed as an elongated hole long in the X direction, and are arranged in a row with intervals in the X direction. The length of each of the slit holes 45a, 45b is shorter than the length of the elongated holes 44a, 44b, and the width of each of the slit holes 45a, 45b is smaller than the width of the elongated holes 44a, 44b. The slit holes 45a are located at the upper side of the second region 42, and the slit holes 45b are located at the lower side of the second region 42. The center of each of the slit holes 45a, 45b in the X direction overlaps with the connecting portions 43a, 43b in the Y direction. The arrangement interval of each of the slit holes 45a, 45b is set to be longer than the length of the connecting portions 43a, 43b in the X direction. As an example, the width of the slits 45a and 45b is 1 mm, and the length is 25 mm.

[0046] 11 shows the results of a simulation of stress distribution when a compressive force or a tensile force is applied to the blank substrate 240 in the Y direction. In the blank substrate 240 according to this embodiment, stress can be concentrated in the second region 42, particularly in the gap between the slit holes 45a, 45b and the long holes 44a, 44b. In this way, by concentrating stress at the end of the blank substrate 240 in the Y direction, the end of the blank substrate 240 in the Y direction can be actively bent when chucked by the substrate holding jig 60, and the amount of deflection of the blank substrate 240 in the entire area in the Y direction can be reduced. Therefore, the end of the blank substrate 240 is less likely to come off the side holding portion 62.

[0047] (effect) According to the second embodiment described above, the following effects are achieved. The blank substrate 240 includes slits 45a and 45b formed in the second region 42 of the blank substrate 240 outside the connecting portions 43a and 43b. According to this configuration, as described above, the blank substrate 240 serving as the raw material for the light source substrate 20 has the slit holes 45a and 45b, so that the end portion of the blank substrate 240 can be prevented from coming off the side surface pressing portion 62.

[0048] Third embodiment A substrate and a display device according to a third embodiment of the present disclosure will be described with reference to the drawings. This embodiment differs from the second embodiment in that slit holes are formed in the first region of the blank substrate. The following description will focus on the differences from the second embodiment.

[0049] As shown in FIG. 12, a blank substrate 340 includes a first region 41, a second region 42, connection portions 43a to 43d, and long holes 44a to 44d, as well as a plurality of slit holes 46a and 46b. The multiple slit holes 46a, 46b are each formed as an elongated hole that is long in the X direction, and are arranged in a row at intervals in the X direction. The length of each of the slit holes 46a, 46b is shorter than the length of the elongated holes 44a, 44b, and the width of each of the slit holes 46a, 46b is smaller than the width of the elongated holes 44a, 44b. The multiple slit holes 46a are positioned within the first region 41 along the upper side of the first region 41, and the multiple slit holes 46b are positioned within the first region 41 along the lower side of the first region 41. The center portions of each of the slit holes 46a, 46b in the X direction overlap with the connecting portions 43a, 43b in the Y direction. The arrangement interval between the slit holes 46a, 46b is set longer than the length of the connecting portions 43a, 43b in the X direction. As an example, the width of the slits 46a and 46b is 1 mm, and the length is 25 mm.

[0050] 13 shows the results of a simulation of stress distribution when a compressive force or a tensile force is applied to the blank substrate 340 in the Y direction. In the blank substrate 340 according to this embodiment, stress can be concentrated at the upper and lower ends of the first region 41, particularly in the gaps between the slit holes 46a, 46b and the connecting portions 43a, 43b. By concentrating stress at the ends of the blank substrate 340 in the Y direction, the ends of the blank substrate 340 in the Y direction can be actively bent when chucked by the substrate holding jig 60, and the amount of deflection of the blank substrate 340 in the entire region in the Y direction can be reduced. Therefore, the ends of the blank substrate 340 are less likely to come off the side holding portions 62.

[0051] The blank substrate 340 is cut along the cut lines CL to produce the light source substrate 320 shown in Fig. 14. The light source substrate 320 is formed with slit holes 46a and 46b.

[0052] (effect) According to the third embodiment described above, the following effects are achieved. The light source substrate 320 includes slit holes 46a and 46b formed as through holes on the inside of the second surface roughness portion 23b or the protrusions 22a and 22b of the light source substrate 320. According to this configuration, as described above, the blank substrate 340 serving as the raw material for the light source substrate 320 has the slits 46a and 46b, so that the ends of the blank substrate 340 can be prevented from coming off the side pressing portions 62.

[0053] The present disclosure is not limited to the above-described embodiments and drawings. Modifications (including deletion of components) can be made as appropriate within the scope of the present disclosure. An example of a modification will be described below.

[0054] (Modification) In the second and third embodiments, the slits 45a, 45b, 46a, and 46b may be formed on the right and left sides of the second region . Furthermore, the slits 45a, 45b, 46a, and 46b may be formed so that a portion of each of them is connected to the side surface of the substrate. The second and third embodiments may be combined to form the slits 45a, 45b, 46a, and 46b in one blank substrate. In each of the above embodiments, the protrusions 22c and 22d are positioned to face each other in the X direction, but this is not limiting, and they may be positioned offset in the Y direction so as not to face each other in the X direction. In addition, in each of the above embodiments, the protrusions 22e and 22f are positioned so as to face each other in the Y direction, but this is not limiting, and they may be positioned so as to be offset in the X direction so as not to face each other in the Y direction. In each of the above embodiments, the light source substrate 20 includes a plurality of protrusions 22a-22f formed on the substrate side surfaces 21a-21d, but the plurality of protrusions 22a-22f may be omitted. In this case, the substrate side surfaces 21a-21d are flat, but the first surface roughness portions 23a and the second surface roughness portions 23b are alternately formed on the substrate side surfaces 21a-21d.

[0055] In each of the above embodiments, the display device 10 is not limited to a configuration including a liquid crystal display panel, and may be a configuration including an organic EL (Electro Luminescence), DMD (Digital Micro mirror Device), or MEMS (Micro Electro Mechanical Systems) mirror.

[0056] The display device 10 in each of the above embodiments may be applied not only to an in-vehicle meter but also to a head-up display device. In this case, the light source substrate 20 of the display device 10 does not need to be curved. In this configuration, the light source substrate 20 is formed thin, for example, to 0.5 mm or less, so that heat dissipation to a heat sink located on the back side of the light source substrate 20 becomes easy.

[0057] In the above embodiments, the thickness of the light source substrate 20, 320 and the blank substrate 40, 240, 340 is 0.5 mm or less, but may be more than 0.5 mm. In each of the above embodiments, the light source substrate 20, 320 was held by the substrate holding portion 16 so that its radius of curvature was 10,000 mm or less, but this is not limited thereto, and the light source substrate 20, 320 may be held by the substrate holding portion 16 so that its radius of curvature exceeds 10,000 mm. The material of the base material of the light source substrate 20, 320 and the blank substrates 40, 240, 340 in each of the above embodiments is not limited to resin, and may be metal such as aluminum. [Explanation of symbols]

[0058] 10 Display device 11 Display surface 15 cases 15a Cover transparent plate material 15b Case body 16 Board holding part 17 Soldering section 17a Cream solder 20,320 Light source board 21a~21d Side of the board 22a~22f Convex part 30 light source 40,140,240,340 Blank Board 41 First area 42 Second area 43a~43f, 143a, 143b Connections 44a~44d long hole 45a, 45b, 46a, 46b Slit holes 50 Display Panel 60 Circuit Board Holder 61 Bottom support part 62 Side clamp 63 Upper surface pressing part 70 Metal Mask P,Q interval CL Cut Line

Claims

1. A substrate on which a light source for illuminating a display is mounted and which is formed in a rectangular flat plate shape along a first direction and a second direction perpendicular to each other, a first surface roughness portion extending along the first direction of the substrate and partially formed on each of two opposing side surfaces; a second surface roughness portion partially formed on each of the two side surfaces and having a surface roughness greater than that of the first surface roughness portion; the first surface roughness portions and the second surface roughness portions are arranged alternately in the first direction, The second surface roughness portions of the two side surfaces are formed at positions not facing each other in the second direction. substrate.

2. the substrate includes a slit formed as a through hole on the inner side of the second surface roughness portion of the substrate, The substrate of claim 1 .

3. A substrate on which a light source for illuminating a display is mounted and which is formed in a rectangular flat plate shape along a first direction and a second direction perpendicular to each other, a plurality of protrusions extending along the first direction of the substrate and partially formed on each of two opposing side surfaces; The plurality of protruding portions are arranged with gaps therebetween in the first direction, The protrusions on the two side surfaces are formed at positions not facing each other in the second direction. substrate.

4. The substrate includes a slit formed as a through hole on the inner side of the protruding portion of the substrate. The substrate according to claim 3 .

5. A substrate which is a raw material for manufacturing a light source substrate on which a light source for illuminating a display is mounted, and which is formed in a rectangular flat plate shape along a first direction and a second direction perpendicular to each other, a first area in which the light source can be mounted; A second region surrounding the first region; a plurality of connection portions connecting the first region and the second region; The plurality of connection portions are arranged with gaps therebetween in the first direction and are formed at positions not facing each other in the second direction. substrate.

6. the substrate includes a slit formed outside the connection portion in the second region of the substrate; The substrate according to claim 5 .

7. The thickness of the substrate is 0.5 mm or less. A substrate according to any one of claims 1 to 6.

8. A substrate according to any one of claims 1 to 4; A plurality of light sources mounted on the substrate; a substrate holder that holds the substrate in a curved state with a radius of curvature of 10,000 mm or less; The display has a curved plate shape that curves along the substrate. Display device.

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