LIGHTING DEVICE, DISPLAY DEVICE AND TELEVISION RECEIVER

• US 20120086875A1
• Filed: 05/17/2010
• Published: 04/12/2012
• Est. Priority Date: 06/30/2009
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Yokota, Masashi
• Granted Patent: US 8,520,150 B2
• Time in Patent Office: Days
• US Class Current: 348/790
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133605 including specially adapted reflectors
• CPC Class Codes: G02F 1/133607 the light controlling member including light directing or refracting elements, e.g. prisms or lenses
• CPC Class Codes: G02F 1/133611 including means for improving the brightness uniformity
• CPC Class Codes: G02F 1/133613 characterized by the sequence of light sources

Abstract

It is an object of the present invention to provide a lighting device realizing reduction in cost and suppression of power consumption and suppressing generation of a lamp image. A lighting device 12 of the present invention includes a plurality of point light sources 80; a chassis 14 housing the point light sources 80 and having an opening 14b through which light from the point light sources 80 exits; and an optical member 15 (15a) facing the point light sources 80 and provided to cover the opening 14b. The point light sources 80 are arranged such that a light source high-density area LH where an arrangement interval thereof is relatively small and a light source low-density area LL where an arrangement interval thereof is relatively large are provided. Light reflection portions 50 reflecting lights from the point light sources 80 are formed in at least a region overlapping with the light source low-density area LL in the optical member 15 (15a).

Claims

1. A lighting device comprising:

a plurality of point light sources;

a chassis housing the point light sources and having an opening through which light emitted from the point light sources exits; and

an optical member facing the point light sources and provided to cover the opening, wherein;

the point light sources are arranged at relatively small intervals in a light source high-density area and the point light sources are arranged at relatively large intervals in a light source low-density area; and

the optical member includes a light reflection portion so as to overlap at least the light source low-density area, the light reflection portion is configured to reflect light emitted from the point light sources.

2. The lighting device according to claim 1, wherein the optical member includes the light reflection portion so as to overlap each of the point light sources in a plan view.

3. The lighting device according to claim 2, wherein the light reflection portion has a planar area greater than each of the point light sources.

4. The lighting device according to claim 1, wherein the light reflection portion is formed such that a light reflectance of a portion of the optical member overlapping the light source low-density area is highest.

5. The lighting device according to claim 1, wherein the optical member includes the light reflection portion on a surface thereof facing one of the point light sources.

6. The lighting device according to claim 1, wherein the light reflection portion is formed by subjecting the optical member to print processing.

7. The lighting device according to claim 1, wherein the chassis includes the light source high-density area in a middle area thereof.

8. The lighting device according to claim 1, wherein the chassis includes the light source low-density area in an outer side portion thereof.

9. The lighting device according to claim 1, wherein the light source high-density area is smaller than the light source low-density area.

10. The lighting device according to claim 1, further comprising a diffuser lens provided on at least a light exit side of the point light sources that are arranged in the light source low-density area, the diffuser lens configured to diffuse light emitted from the point light sources.

11. The lighting device according to claim 10, wherein the diffuser lens has a circular shape in a plan view.

12. The lighting device according to claim 10, wherein:

the diffuser lens has a light entrance surface facing one of the point light sources and receiving light from the point light source;

the light entrance surface has a light entrance side recess so as to overlap the point light source, the light entrance side recess is recessed to the optical member side; and

the light entrance side recess has a side wall inclined so as to face the point light source.

13. The lighting device according to claim 10, wherein:

the diffuser lens has a light exit surface facing the optical member and light emitted from the point light source and entering the diffuser lens exits from the light exit surface; and

the light exit surface has a light exit side recess so as to overlap the point light source, the light exit side recess is recessed to the point light source side.

14. The lighting device according to claim 1, wherein at least the light entrance surface of the diffuser lens is subjected to surface roughness processing.

15. The lighting device according to claim 1, wherein the optical member is a light diffusing member configured to diffuse light from the point light sources.

16. The lighting device according to claim 1, wherein the point light sources are LEDs.

17. The display device comprising:

the lighting device according to claim 1; and

a display panel configured to provide display using light from the lighting device.

18. The display device according to claim 17, wherein the display panel is a liquid crystal panel using liquid crystals.

19. A television receiver comprising the display device according to claim 17.