Thin type luminaire which suppresses luminance unevenness, and display device

Abstract

To achieve thinning while suppressing luminance unevenness.SOLUTION: A luminaire 30 includes: a plurality of light sources 52; a substrate 51 on which the plurality of light sources 52 are mounted; a diffusion member 60 which diffuses light from the plurality of light sources 52; and a support member 70 which is disposed on a mounting surface 51A of the substrate 51, and supports the diffusion member 60. The support member 70 includes: a plurality of insertion holes 73 into which at least one light source 52 is inserted; and a plurality of protrusion parts 75 which stand surrounding each insertion hole 73, and protrude to the diffusion member 60 side. A main surface 63 on the support member 70 side of the diffusion member 60 includes: a recess part 63A which is overlapped and engaged with the protrusion part 75 of the support member 70; and a protrusion part 63B which is overlapped with the insertion hole 73.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present technology relates to a lighting device and a display device.

Background Art

[0002] Conventionally, as a liquid crystal display device, a so-called direct-lit backlight device in which a light source is arranged on the entire back surface side of a liquid crystal panel is known, and an example thereof is disclosed in Patent Document 1. The backlight device (LED lighting structure) described in Patent Document 1 includes a plurality of LEDs and a diffusion plate that is separated from the plurality of LEDs by a predetermined distance and has an uneven shape with a thick portion directly above each LED. By thickening the portion directly above the LED that is irradiated with the strongest light in the diffusion plate to attenuate the light, it is said that the light irradiated on the liquid crystal panel can be equalized.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Since the backlight device described in Patent Document 1 needs to separate the LED and the diffusion plate by a predetermined distance or more, there is a situation where it is difficult to make it thinner.

[0005] The technology described in the present specification has been completed based on the above circumstances, and an object thereof is to make it thinner while suppressing luminance unevenness.

Means for Solving the Problems

[0006] (1) The lighting device related to this technology includes a plurality of light sources arranged side by side in a plane, a substrate on which the plurality of light sources are mounted, a diffusion member that diffuses light from the plurality of light sources, and a support member disposed on the mounting surface of the substrate that supports the diffusion member. The support member has a plurality of insertion holes through which at least one of the light sources is inserted, and a plurality of protruding portions that stand upright surrounding each insertion hole and protrude toward the diffusion member side. The main surface of the diffusion member on the support member side includes a recess that overlaps and engages with the plurality of protruding portions of the support member, and a convex portion that overlaps with the plurality of insertion holes.

[0007] (2) Further, in addition to the above (1), the lighting device may have, in the recess of the main surface of the diffusion member, a bulging portion that protrudes toward the support member side.

[0008] (3) Further, in addition to the above (1) or (2), the planar size of the diffusion member is smaller than the planar size of the support member. The peripheral portion of the support member has an inner peripheral side surface that faces the outer peripheral side surface of the peripheral portion of the diffusion member, and the inner peripheral side surface of the support member and the outer peripheral side surface of the diffusion member may be arranged with a gap therebetween.

[0009] (4) Further, in addition to any one of the above (1) to (3), the diffusion member and the support member may be integrally provided.

[0010] (5) The display device related to this technology includes any one of the lighting devices of the above (1) to (3), and a display panel that performs display using the light from the lighting device.

[0011] (6) Further, in addition to the above (5), the display panel may be a liquid crystal panel having a liquid crystal layer.

Advantages of the Invention

[0012] According to this technology, it is possible to reduce the thickness while suppressing uneven brightness.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0014] <Embodiment 1> Embodiment 1 will be described with reference to FIGS. 1 to 6. In the present embodiment, a liquid crystal display device 10 (an example of a display device) including a backlight device 30 (an example of an illumination device) will be exemplified. In a part of each drawing, the X-axis, Y-axis, and Z-axis are shown, and the axial directions are drawn so as to be common directions in each drawing.

[0015] As shown in FIG. 1, the liquid crystal display device 10 includes a liquid crystal panel (an example of a display panel) 20 that displays an image, and a backlight device 30 that irradiates light onto the liquid crystal panel 20, and these are integrally held by a bezel 14 and a frame 15 having a frame shape. The liquid crystal panel 20, the backlight device 30, and the liquid crystal display device 10 have a horizontally long rectangular shape in plan view, the long side direction coincides with the X-axis direction in each drawing, the short side direction coincides with the Y-axis direction, and the thickness direction coincides with the Z-axis direction. The side of the liquid crystal panel 20 in the Z-axis direction is defined as the front side, and the side of the backlight device 30 is defined as the back side. However, the planar shape is not limited, and it may be a vertically long rectangular shape or the like.

[0016] The bezel 14 extends along the peripheral portion on the front side of the liquid crystal panel 20 and constitutes the appearance on the front side of the liquid crystal display device 10. The bezel 14 is made of, for example, a metal having excellent rigidity or a resin having light-shielding properties. The frame 15 is made of, for example, a resin such as white having excellent light reflectivity.

[0017] The liquid crystal panel 20 is sandwiched between the bezel 14 and the frame 15 in a posture where the display surface capable of displaying an image faces the front side. The liquid crystal panel 20 has a configuration in which a pair of transparent substrates are bonded together with a predetermined gap therebetween, and a liquid crystal layer is encapsulated between the two glass substrates. Polarizing plates are supposed to be arranged outside the two glass substrates. The in-plane of the liquid crystal panel 20 is divided into a display area for displaying an image and a non-display area that forms a frame shape so as to surround the display area and in which no image is displayed.

[0018] The backlight device 30 includes a plurality of LEDs 52 (an example of a light source), an LED substrate (an example of a light source substrate) 51 on which the plurality of LEDs 52 are mounted, a diffusion member 60, a support member 70, a plurality of optical sheets 33, and a chassis 40. The LEDs 52 are arranged in a planar manner on the back side (lower side) of the liquid crystal panel 20, and the backlight device 30 is a so-called direct-lit backlight device.

[0019] The chassis 40 has a tray shape that opens toward the light-emitting side (the liquid crystal panel 20 side) and is made of, for example, metal (such as stainless steel or aluminum). The LED substrate 51 is housed in the bottom 41 of the chassis 40. The peripheral portion 42 of the chassis 40 protrudes toward the front side to form a side wall, and the lower portion 15A of the frame 15 is inserted between the peripheral portion (side wall) 42 and the peripheral portion 71 of the support member 70.

[0020] The LED 52 has a rectangular parallelepiped shape. As shown in FIGS. 1 and 2, the bottom surface is arranged on the front plate surface (mounting surface) 51A of the LED substrate 51, and the upper surface on the side opposite to the bottom surface becomes the light emitting surface 52A, which is a so-called top emission type (top view type). The optical axis of the LED 52 (the traveling direction of the light with the highest peak of the emission intensity of the emitted light) is in the Z-axis direction. The LED 52 is a white light emitting type, but a single color light emitting type (for example, blue light emitting type) may be used. In that case, in order to emit white synthesized light (mixed light), it is preferable to use a wavelength conversion sheet as one of the optical sheets 33.

[0021] The various optical sheets 33 are arranged intervening between the diffusion member 60 and the liquid crystal panel 20, and impart a predetermined optical action to the emitted light. There are various kinds of optical sheets 33 known, and one kind or a plurality of kinds are appropriately used according to the use of the liquid crystal display device 10 etc. (three are shown in the figure). As the optical sheet, for example, a brightness improvement sheet that imparts a condensing action to the emitted light and enhances the front brightness is used.

[0022] As shown in FIG. 3, the LED 52 is arranged in a planar manner on the front plate surface (mounting surface 51A) of the LED substrate 51 having a rectangular shape in plan view. More specifically, the LED 52 is arranged in a matrix almost at equal intervals along the X-axis direction (row direction) and the Y-axis direction (column direction) respectively. However, the planar size of the LED substrate 51, as well as the arrangement pitch and number of the LEDs 52, can be appropriately changed according to the screen size, use, and required accuracy of the liquid crystal panel 20.

[0023] As shown in FIGS. 1 to 3, the support member 70 is disposed on the mounting surface 51A of the LED substrate 51 and covers the entire mounting surface 51A from the front side. The support member 70 is provided to support the diffusion member 60. The support member 70 is formed to be one size larger than the diffusion member 60 and the LED substrate 51 in plan view, and has a horizontally long rectangular shape in this embodiment. The support member 70 is made of a resin such as white polycarbonate having excellent light reflectivity, and each part is integrally formed. The higher the light reflectivity of the support member 70, the more preferable it is to enhance the light utilization efficiency.

[0024] The peripheral edge portion 71 of the support member 70 has a first protrusion 71A that protrudes toward the light-emitting side (the liquid crystal panel 20 side) and a second protrusion 71B that protrudes toward the bottom 41 side of the chassis 40. Among the peripheral edge portion 71 of the support member 70, an optical sheet 33 is installed on the first protrusion 71A, and the peripheral edge portion 61 of the diffusion member 60 is installed inside the first protrusion 71A (on the side opposite to the peripheral edge portion 42 of the chassis 40). Also, an LED substrate 51 is installed in the space formed between the support member 70 and the bottom 41 of the chassis 40 by the second protrusion 71B.

[0025] As shown in FIGS. 3 and 4, the support member 70 has a plurality of insertion holes 73 and a plurality of protruding portions 75. The insertion holes 73 have a shape and size through which at least one LED 52 can be inserted. Each insertion hole 73 according to the present embodiment has a rectangular shape following the LED 52 and has a size through which at least one LED 52 can be inserted. The LED 52 and the mounting surface 51A of the LED substrate 51 in the vicinity thereof are exposed to the front side from the insertion hole 73, but the insertion hole 73 may be formed to have a size that only inserts the light-emitting surface 52A of the LED 52. When a part of the mounting surface 51A is exposed from the insertion hole 73, in order to improve the light utilization efficiency of this exposed portion, a high-reflection coating (white paint) may be applied to the mounting surface 51A, or a reflective sheet may be provided.

[0026] The protruding portion 75 of the support member 70 stands upright surrounding the insertion hole 73 and the LED 52 inserted therein. The protruding portion 75 is located between two adjacent insertion holes 73 (that is, between the LEDs 52) and between the peripheral edge portion 71 of the support member 70 and the insertion hole 73 (that is, between the peripheral edge portion 71 and the LED 52). The protruding portion 75 is provided in a lattice shape when viewed in a plane and extends in the X-axis direction and the Y-axis direction.

[0027] As shown in FIG. 2, the protruding portion 75 protrudes in a mountain-shaped cross section toward the light-emitting side (the liquid crystal panel 20 side, the diffusion member 60 side) and includes an inclined surface 75A that protrudes from the LED substrate 51 side to the front side. By the inclined surface 75A, the light emitted from each LED 52 and reaching the inclined surface 75A is reflected so as to be directed to the front side.

[0028] The protruding surface (front end surface on the front side) 75B of the protruding portion 75 having a cross-sectional mountain shape has a partially recessed shape. More specifically, as shown in FIG. 2, the protruding surface 75B is recessed such that the height of the central portion of the cross-sectional mountain shape (the central portion in the X-axis direction in FIG. 2) is smaller than the height of the connection portion with the inclined surface 75A. This recessed portion 75B1 has a substantially semi-elliptical shape in cross-section in this embodiment, but may have other shapes as long as it is recessed. The recessed portion 75B1 is not formed on the protruding surface 75B of the protruding portion 75 located at the peripheral portion 71 of the support member 70, but is formed on the protruding surface 75B located outside the peripheral portion 71. Therefore, the recessed portion 75B1 is provided in a grid pattern in plan view and extends in the X-axis direction and the Y-axis direction.

[0029] The diffusion member 60 diffuses the light emitted from the LED 52 while transmitting it. The diffusion member 60 is a thicker member than the optical sheet 33 (for example, about 3 mm thick), and has a horizontally long rectangular shape in plan view in this embodiment as shown in FIG. 5. The diffusion member 60 is made of a resin material of a different type from the support member 70, has a lower light reflectance than the support member 70, and also has a different linear expansion rate. It is preferable that the diffusion member 60 uses a material having an excellent balance between the light transmittance and the haze value so as to diffuse while suppressing luminance unevenness while transmitting light. The diffusion member 60 has, for example, a configuration in which a large number of diffusion particles are dispersed in a transparent resin base material.

[0030] As shown in FIG. 2, the diffusion member 60 has a concavo-convex shape on the first main surface 63 on the support member 70 side (LED 52 side) and a flat shape on the second main surface 65 on the optical sheet 33 side. The protruding portion 75 of the support member 70 is formed following the concavo-convex shape of the first main surface 63, whereby the diffusion member 60 is supported by the support member 70 and is stably installed on the support member 70.

[0031] The first main surface 63 of the diffusion member 60 includes a concave portion 63A that overlaps and engages with the protruding portion 75 of the support member 70, and a convex portion 63B that overlaps with the insertion hole 73 of the support member 70. The concave portion 63A engages with the protruding surface 75B of the protruding portion 75 of the support member 70. The convex portion 63B faces the light emitting surface 52A of the LED 52 protruding from the insertion hole 73 with a slight gap therebetween.

[0032] In this way, the thickness of the diffusion member 60 is large at the portion overlapping with the LED 52 and small at the portion overlapping between the LEDs 52 (the portion non-overlapping with the LED 52), and uneven brightness (so-called LED unevenness) due to the arrangement of the LEDs 52 can be suppressed. Further, by disposing the support member 70 on the mounting surface 51A of the LED substrate 51 and installing the diffusion member 60 on the support member 70, the diffusion member 60 and the LED 52 can be brought as close as possible, and the separation distance between the two can be reduced. As a result, it is possible to realize thinning while suppressing uneven brightness of the backlight device 30.

[0033] Also, a part of the concave portion 63A of the first main surface 63 of the diffusion member 60 has a shape protruding toward the support member 70 side. More specifically, the concave portion 63A has a bulging portion 66 in which the central portion in the width direction (X-axis direction in FIG. 2) protrudes (bulges) toward the support member 70 side. In the present embodiment, the bulging portion 66 has a substantially semi-elliptical shape in a cross-sectional view, but may have other shapes as long as it protrudes. As shown in FIGS. 5 and 6, the bulging portion 66 is formed in the concave portion 63A located between two adjacent convex portions 63B. The bulging portions 66 are provided in a lattice pattern in a plan view and extend in the X-axis direction and the Y-axis direction.

[0034] By forming the bulging portion 66 and partially increasing the thickness of the concave portion 63A, the strength can be reinforced. The diffusion member 60 has a small thickness in the concave portion 63A and a lower strength than the convex portion 68B, but the bulging portion 66 can reinforce the concave portion 63A and suppress the situation of breakage.

[0035] Further, as shown in FIG. 1, the planar size of the diffusion member 60 is slightly smaller than the planar size of the support member 70. The peripheral portion 61 of the diffusion member 60 is installed on the protruding portion 75 located on the peripheral portion 71 of the support member 70. The outer peripheral side surface 61A of the peripheral portion 61 of the diffusion member 60 is arranged with a clearance G1 from the inner peripheral side surface 71A1 of the first protrusion 71A provided on the peripheral portion 71 of the support member 70.

[0036] In this way, even when the diffusion member 60 and the support member 70 are made of different materials and have different linear expansion coefficients, a clearance space (i.e., the clearance G1) is ensured when the outer peripheral side surface 61A of the diffusion member 60 thermally expands.

[0037] <Embodiment 2> The backlight device 130 according to Embodiment 2 and the liquid crystal display device 110 including the same will be described with reference to FIG. 7. In this embodiment, it is different from Embodiment 1 in that the diffusion member 160 and the support member 170 are integrally provided. In this embodiment, the same reference numerals are used for the same parts as in the above embodiment, and duplicate descriptions of the same structure, operation, and effect are omitted.

[0038] The diffusion member 160 and the support member 170 are integrally formed, for example, by simultaneous molding of different materials, but the manufacturing method is not limited as long as they are integrally provided as one molded product. By integrally providing the diffusion member 160 and the support member 170, it is possible to suppress the situation where the two rub against each other and generate abnormal noise, and it is easy to reduce costs.

[0039] <Other Embodiments> The present invention is not limited to the embodiments described by the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.

[0040] (1) As long as the bulging portions 66 of the diffusion members 60 and 160 can reinforce the concave portions 63A, they may be provided more locally (for example, in a scattered manner) when viewed in a plane.

[0041] (2) The bezel 14 and the frame 15 may be non-frame-shaped, and either one of them alone may hold the liquid crystal panel 20 and the backlight devices 30 and 130.

Explanation of Reference Numerals

[0042] 10, 110... Liquid crystal display device (display device), 20... Liquid crystal panel (display panel), 30, 130... Backlight device (lighting device), 51... LED substrate (light source substrate), 51A... Mounting surface, 52... LED (light source), 60, 170... Diffusion member, 61... Peripheral portion, 61A... Outer peripheral side surface, 63... First main surface (main surface), 63A... Concave portion, 63B... Convex portion, 66... Bulging portion, 70, 170... Support member, 71... Peripheral portion, 71A1... Inner peripheral side surface, 73... Insertion hole, 75... Protruding portion

Claims

1. A plurality of light sources arranged side by side in a plane, a substrate on which the plurality of light sources are mounted, a diffusion member that diffuses light from the plurality of light sources, and a support member disposed on the mounting surface of the substrate and supporting the diffusion member, wherein the support member has a plurality of insertion holes through which at least one of the light sources is inserted, and a plurality of protruding portions that stand up surrounding each of the insertion holes and protrude toward the diffusion member side, and a main surface of the diffusion member on the support member side includes a concave portion that overlaps and engages with the plurality of protruding portions of the support member and a convex portion that overlaps with the plurality of insertion holes. The lighting device.

2. The lighting device according to claim 1, wherein the concave portion on the main surface of the diffusion member has a bulging portion protruding toward the support member side.

3. The planar size of the diffusion member is smaller than the planar size of the support member, the peripheral edge portion of the support member has an inner peripheral side surface facing the outer peripheral side surface of the peripheral edge portion of the diffusion member, and the inner peripheral side surface of the support member and the outer peripheral side surface of the diffusion member are arranged with a gap therebetween. The lighting device according to claim 1 or 2.

4. The lighting device according to claim 1 or 2, wherein the diffusion member and the support member are integrally provided.

5. A display device comprising the lighting device according to claim 1 or 2 and a display panel that performs display using light from the lighting device.

6. The display device according to claim 5, wherein the display panel is a liquid crystal panel having a liquid crystal layer.

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