Backlight module with light attenuated thermal expansion gap and liquid crystal display with same

• US 20070052880A1
• Filed: 09/05/2006
• Published: 03/08/2007
• Est. Priority Date: 09/02/2005
• Status: Abandoned Application

• Current Assignee: InnoLux Corporation
• Original Assignee: Innolux Display Corporation (InnoLux Corporation)
• Inventors: Chen, Fei-Hong, Lv, Song, Chang, Chih-Hung
• Application Number:
  US11/515,657
• Publication Number:
  US 20070052880A1
• Time in Patent Office: Days
• US Class Current: 349/58
• CPC Class Codes: G02B 6/0016 Grooves, prisms, gratings, scattering particles or rough surfaces
• CPC Class Codes: G02B 6/002 by shaping at least a portion of the light guide, e.g. with collimating, focussing or diverging surfaces
• CPC Class Codes: G02B 6/0031 Reflecting element, sheet or layer
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side

Abstract

An exemplary backlight module (4) includes a frame (44) and a light guide plate (40) received in the frame. The light guide plate has a top light emitting surface (404). The frame and an end (408) of the light guide plate cooperatively define a gap (46) therebetween. The gap has a narrowed exit (462) adjacent to the light emitting surface, whereby light beams are prevented from either or both of leaking out from the end of the light guide plate and leaking out from the gap via the narrowed exit.

Claims

1. A backlight module comprising:

a frame; and

a light guide plate received in the frame, the light guide plate comprising a top light emitting surface;

the frame and an end of the light guide plate cooperatively defining a gap therebetween;

wherein the gap has a narrowed exit adjacent to the light emitting surface,

whereby light beams are prevented from either or both of leaking out from the end of the light guide plate and leaking out from the gap via the narrowed exit.

2. The backlight module in claim 1, wherein the light guide plate further comprises a side surface adjoining the light emitting surface, and a bottom surface.

3. The backlight module in claim 2, wherein the side surface maintains a predetermined acute angle relative to the light emitting surface.

4. The backlight module in claim 3, wherein a critical angle of the side surface is less than incident angles of light beams striking the side surface from within the light guide plate.

5. The backlight module in claim 4, wherein the side surface is planar.

6. The backlight module in claim 4, wherein the side surface is curved.

7. The backlight module in claim 2, wherein the frame comprises an inner side surface adjacent to the side surface of the light guide plate.

8. The backlight module in claim 7, wherein the inner side surface is oriented at a predetermined obtuse angle relative to the light emitting surface of the light guide plate.

9. The backlight module in claim 8, wherein most of light beams that strike the inner side surface are reflected therefrom.

10. The backlight module in claim 9, wherein the inner side surface is planar.

11. The backlight module in claim 9, wherein the inner side surface is curved.

12. The backlight module in claim 8, wherein the inner side surface is jagged.

13. The backlight module in claim 1, wherein the frame is made from white polycarbonate.

14. The backlight module in claim 1, wherein the frame is made from plastic.

15. A backlight module comprising:

a frame having an inner side surface; and

a light guide plate received in the frame, the light guide plate comprising an end facing the inner side surface;

wherein the end is jagged for preventing light beams from leaking out from the light guide plate therethrough.

16. A liquid crystal display comprising:

a liquid crystal panel; and

a backlight module positioned adjacent to the liquid crystal panel, the backlight module comprising;

a frame; and

a light guide plate received in the frame, the light guide plate comprising a top light emitting surface;

the frame and an end of the light guide plate cooperatively defining a gap therebetween;

wherein the gap has a narrowed exit adjacent to the light emitting surface,

whereby light beams are prevented from either or both of leaking out from the end of the light guide plate and leaking out from the gap to the liquid crystal panel via the narrowed exit.