Surface lighting device with closed oblique reflector

• US 7,134,777 B2
• Filed: 03/22/2004
• Issued: 11/14/2006
• Est. Priority Date: 03/21/2003
• Status: Expired due to Fees

• Current Assignee: Hon Hai Precision Industry Co., Ltd.
• Original Assignee: Hon Hai Precision Industry Co., Ltd.
• Inventors: Sung, Chang-Chieh
• Primary Examiner(s): Husar, Stephen
• Assistant Examiner(s): Cranson, Jr., James W
• Application Number:
  US10/807,211
• Publication Number:
  US 20040184258A1
• Time in Patent Office: 967 Days
• Field of Search: 362608- 10, 362/609, 362/610, 362/611, 362/612, 362/613, 362/614, 362/615, 362/616, 362/621, 362/622, 362/555, 362/560
• US Class Current: 362/609
• CPC Class Codes: G02B 6/0028 Light guide, e.g. taper
• CPC Class Codes: G02B 6/0038 Linear indentations or grooves, e.g. arc-shaped grooves or meandering grooves, extending over the full length or width of the light guide
• CPC Class Codes: G02B 6/0046 Tapered light guide, e.g. wedge-shaped light guide
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer

Abstract

A surface lighting device (1) includes a light guide plate (11), a point light source (14), and a light reflector (13) substantially juxtaposed with the light guide plate. The light guide plate has a light incident surface (111). The point light source is located between one end of the light reflector and the light incident surface. The light reflector comprises a reflecting portion (131) obliquely opposite to the light incident surface. The reflecting portion is adapted to receive light beams emitted from the point light source, and reflect the received light into the light incident surface of the light guide plate.

Claims

1. A surface lighting device for a display device, comprising:

a light guide plate having a light incident surface;

a light reflector substantially juxtaposed with the light guide plate, the light reflector having a reflecting portion obliquely opposite to the light incident surface along a lengthwise direction of the light incident surface; and

a point light source for emitting light beams, the point light source located between one end of the light reflector and the light incident surface, the point light source having a light emitting surface located inside the light reflector;

wherein the light reflector receives the light beams emitted from the point light source, and reflects the light beams into the light incident surface of the light guide plate.

2. The surface lighting device as claimed in claim 1, further comprising a brightness enhancement film sandwiched between the light incident surface and the light reflector.

3. The surface lighting device as claimed in claim 1, wherein the reflecting portion is a sidewall of the light reflector, and the light reflector further comprises a planar top wall and a planar bottom wall adjoining the sidewall.

4. The surface lighting device as claimed in claim 1, wherein the light reflector has an arch-shaped cross-section.

5. The surface lighting device as claimed in claim 1, wherein the reflecting portion comprises a plurality of prisms formed on an inside of the light reflector.

6. The surface lighting device as claimed in claim 1, wherein the light reflector is generally L-shaped.

7. The surface lighting device as claimed in claim 1, wherein an opposite end of the light reflector connects with the light incident surface.

8. The surface lighting device as claimed in claim 7, wherein said opposite end is arcuate.

9. The surface lighting device as claimed in claim 7, wherein the light reflector is arcuate.

10. The surface lighting device as claimed in claim 1, wherein the surface lighting device comprises two light reflectors and two corresponding point light sources, the light reflectors and the light sources being arranged at opposite sides of the light guide plate respectively.

11. The surface lighting device as claimed in claim 10, wherein the light reflectors are arranged symmetrically opposite to each other at the opposite sides of the light guide plate.

12. The surface lighting device as claimed in claim 10, wherein the two light reflectors are arranged opposite to each other such that the point light sources are diagonally opposite from each other.

13. A surface lighting device for a display device, comprising:

a light guide plate having a light incident surface;

a mount portion for fixing a point light source thereon; and

a light reflector coupled with the light incident surface of the guide plate;

wherein, the light guide plate, the mount portion and the light reflector cooperate together to define a closed space therebetween, said space being tapered in a direction away from the point light source.

14. The surface lighting device as claimed in claim 13, wherein a light emitting surface of the point light source is located inside the space.

15. The surface lighting device as claimed in claim 13, wherein said space is essentially of a triangular configuration, and the mounting portion is one side of said triangular configuration and essentially extends in a lengthwise direction of the light guide plate.

16. A surface lighting device for a display device, comprising:

a light guide plate having a light incident surface; and

a light reflector coupled with the light guide plate and having a sidewall opposite to the light incident surface;

wherein, one end of the sidewall connects with the light incident surface, an opposite end of the sidewall is spaced apart from the light incident surface, a point light source is provided between the opposite end of the sidewall and the light incident surface.

17. The surface light device as claimed in claim 16, wherein the point light sources is directed toward said end connecting said side wall and said light incident surface.

18. The surface lighting device as claimed in claim 16, wherein the point light source is positioned on a mount portion.

19. The surface lighting device as claimed in claim 18, wherein the mount portion, the light guide plate and the light reflector cooperatively form a closed space therebetween.