Backlight structure with reflective light source cover and manufacturing method

• US 8,727,595 B2
• Filed: 09/02/2011
• Issued: 05/20/2014
• Est. Priority Date: 09/09/2010
• Status: Active Grant

• Current Assignee: AU Optronics Corporation
• Original Assignee: AU Optronics Corporation
• Inventors: Lai, Ching-Kun
• Primary Examiner(s): Negron, Ismael
• Application Number:
  US13/224,447
• Publication Number:
  US 20120063163A1
• Time in Patent Office: 991 Days
• Field of Search: 362/23.09, 362/23.1, 362/23.14, 362/23.16, 362/23.17, 362/612, 362/613, 362/608, 362/609, 349/62, 349/65
• US Class Current: 362/609
• CPC Class Codes: G02B 6/0031 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0036 2-D arrangement of prisms, protrusions, indentations or roughened surfaces
• CPC Class Codes: G02B 6/0061 to provide homogeneous light output intensity
• CPC Class Codes: G02B 6/0068 Arrangements of plural sources, e.g. multi-colour light sources
• CPC Class Codes: G02B 6/0073 Light emitting diode [LED]
• CPC Class Codes: G02B 6/0091 of the light source relative to the light guide G02B6/0021 takes precedence
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

A backlight structure includes a light guide plate, at least one light source module, and a reflective cover. The light guide plate has a light incident side and a light-exiting surface, wherein the light-exiting surface is formed at an edge of the light incident side. The light source module includes a substrate and at least one light emitting element, wherein the light emitting element disposed on the substrate emits light to the light incident side. The reflective cover has a first reflecting portion and a second reflecting portion, wherein the second reflecting portion extends from the first reflecting portion disposed between a surface of the substrate and the light incident side of the light guide plate and covers a part of the light-exiting surface, so that the reflective cover reflects light emitted from the light emitting element to the light guide plate.

Claims

1. A backlight structure, comprising:

a light guide plate having a light incident side and a light-exiting surface formed on an edge of the light incident side;

wherein the light guide plate further comprises a bottom surface opposite to the light-exiting surface;

at least one light source module comprising a substrate and at least one light emitting element, wherein the substrate has a support surface facing the light incident side, the light emitting element is disposed on the support surface and emits light to the light incident side;

a portion of the bottom surface proximate the light emitting element is an unpatterned region, and at least one optical microstructure is formed on the bottom surface outside the unpatterned region; and

a reflective cover having a first reflecting portion and a second reflecting portion connected to each other, wherein the first reflecting portion is disposed between the light source module and the light incident side of the light guide plate, the second reflecting portion extends from the first reflecting portion toward the light guide plate, traverses a border between the light incident side and the light-exiting surface, and covers a part of the light-exiting surface, the first reflecting portion and the second reflecting portion reflect light emitted from the light emitting element to the light guide plate.

2. The backlight structure of claim 1, wherein the first reflecting portion is formed with a through hole to allow the light emitting element to pass therethrough.

3. The backlight structure of claim 1, wherein the first reflecting portion is formed with a recess on one side to allow the light emitting element to pass therethrough.

4. The backlight structure of claim 1, further comprising a back plate, wherein the light guide plate further comprises a bottom surface opposite to the light-exiting surface, and the bottom surface is attached onto the back plate.

5. The backlight structure of claim 1, wherein the light guide plate is an optical glass plate.

6. The backlight structure of claim 5, wherein the material of the optical glass plate is selected from soda glass, silica glass, and ultra clear glass.

7. The backlight structure of claim 5, further comprising at least one optical film attached onto the light-exiting surface of the light guide plate.

8. The backlight structure of claim 7, wherein the at least one optical film comprising multiple optical films overlapped with each other and attached onto the light-exiting surface of the light guide plate.

9. The backlight structure of claim 7, wherein the optical film is a multilayer complex film.

10. The backlight structure of claim 5, further comprising a reflector, wherein the light guide plate further comprises a bottom surface opposite to the light-exiting surface, and the reflector is attached onto the bottom surface and reflects light emitted from the light emitting element to the light guide plate.

11. The backlight structure of claim 10, further comprising a glue layer disposed between the reflector and the light guide plate, and the refractive index of the glue layer is substantially equal to 1.0.

12. The backlight structure of claim 10, further comprising a back plate, wherein the reflector has a first surface and a second surface opposite to the first surface, the first surface is attached onto the bottom surface of the light guide plate, and the second surface is attached onto the back plate.

13. A method for manufacturing a backlight structure, comprising:

providing a light guide plate comprising a light incident side, a light-exiting surface formed on an edge of the light incident side, and a bottom surface opposite to the light-exiting surface;

forming an unpatterned region on a portion of the bottom surface proximate the light emitting element, and forming at least one optical microstructure on the bottom surface outside the unpatterned region;

disposing at least one light source module comprising a substrate and at least one light emitting element, the substrate having a support surface, the light emitting element being disposed on the support surface, wherein the support surface faces the light incident side, so that the light emitting element emits light to the light incident side; and

disposing a reflective cover having a first reflecting portion and a second reflecting portion connected to each other, wherein the first reflecting portion is disposed between the light source module and the light incident side of the light guide plate, the second reflecting portion extends from the first reflecting portion toward the light guide plate, traverses a border between the light incident side and the light-exiting surface, and covers a part of the light-exiting surface, the first reflecting portion and the second reflecting portion reflect light emitted from the light emitting element to the light guide plate.

14. The method for manufacturing a backlight structure of claim 13, further comprising forming a through hole on the first reflecting portion to allow the light emitting element to pass therethrough.

15. The method for manufacturing a backlight structure of claim 13, further comprising forming a recess on one side of the second reflecting portion to allow the light emitting element to pass therethrough.

16. The method for manufacturing a backlight structure of claim 13, wherein the light guide plate further comprises a bottom surface opposite to the light-exiting surface, and the method further comprises attaching the bottom surface onto a back plate.

17. The method for manufacturing a backlight structure of claim 13, wherein the light guide plate is an optical glass plate.

18. The method for manufacturing a backlight structure of claim 17, wherein the material of the optical glass plate is selected from soda glass, silica glass, and ultra clear glass.

19. The method for manufacturing a backlight structure of claim 17, further comprising disposing at least one optical film, so that the optical film is attached onto the light-exiting surface of the light guide plate.

20. The method for manufacturing a backlight structure of claim 19, comprising overlapping multiple optical films with each other, so that the optical films are attached onto the light-exiting surface of the light guide plate.

21. The method for manufacturing a backlight structure of claim 19, wherein the optical film is a multilayer complex film.

22. The method for manufacturing a backlight structure of claim 17, wherein the light guide plate further comprises a bottom surface opposite to the light-exiting surface, the method further comprises disposing a reflector, so that the reflector is attached onto the bottom surface of the light guide plate and reflects light emitted from the light emitting element to the light guide plate.

23. The method for manufacturing a backlight structure of claim 22, further comprising disposing a glue layer between the reflector and the light guide plate, wherein the refractive index of the glue layer is substantially equal to 1.0.

24. The method for manufacturing a backlight structure of claim 22, wherein the reflector has a first surface and a second surface opposite to the first surface, the first surface is attached onto the bottom surface of the light guide plate, and the method further comprises attaching the second surface onto a back plate.