LIGHT GUIDE PLATES AND BACKLIGHT MODULE

• US 20100033955A1
• Filed: 06/16/2009
• Published: 02/11/2010
• Est. Priority Date: 08/09/2008
• Status: Active Grant

• Current Assignee: Hon Hai Precision Industry Co., Ltd., Tsinghua University
• Original Assignee: Hon Hai Precision Industry Co., Ltd., Tsinghua University
• Inventors: ZHAO, YAN, ZHU, JUN, JIN, GUO-FAN, ZHANG, HE
• Granted Patent: US 8,057,056 B2
• Time in Patent Office: Days
• US Class Current: 362/97.100
• CPC Class Codes: G02B 6/0018 Redirecting means on the surface of the light guide
• 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: G02F 1/133603 with LEDs

Abstract

A light guide plate includes a body having a bottom surface and a light output surface opposite to the bottom surface. A scattering structure is formed on the bottom surface. The scattering structure includes a plurality of scattering dots located in the form of a plurality of concentric shapes about the center. A backlight module using the light guide plate is also provided.

Claims

1. A light guide plate, comprising:

a body having a bottom surface having a center, a light output surface opposite to the bottom surface; and

a first scattering structure formed on the bottom surface, wherein the first scattering structure comprises a plurality of scattering dots form a plurality of shapes concentrically located around the center.

2. The light guide plate as claimed in claim 1, wherein the shapes are round, polygonal or both round and polygonal.

3. The light guide plate as claimed in claim 2, wherein the scattering dots adjacent to the center are arranged in a plurality of concentric circles, and the scattering dots adjacent to the edge of the bottom surface are arranged in a plurality of concentric polygons.

4. The light guide plate as claimed in claim 2, wherein a ratio of the number of circles to the number of polygons is less than 20:

1.

5. The light guide plate as claimed in claim 2, wherein a second plurality of scattering dots are located in an area between the most outside of concentric circle and the most inside of concentric polygon;

the second plurality of scattering dots are arranged in a circular arcs.

6. The light guide plate as claimed in claim 2, wherein the polygon is substantially corresponds to the shape of the light guide plate.

7. The light guide plate as claimed in claim 1, wherein two adjacent shapes have a distance between them that ranges from about 0.5 millimeters to about 2 millimeters.

8. The light guide plate as claimed in claim 1, wherein a density of the scattering dots increases further away from the center.

9. The light guide plate as claimed in claim 1, wherein the scattering dots on the same shape are dispersed uniformly, and a distance between adjacent two scattering dots on the same shape ranges from about 0.1 millimeters to about 1 millimeter.

10. The light guide plate as claimed in claim 1, wherein a density of the scattering dots on each shape increases further away from the center.

11. The light guide plate as claimed in claim 1, wherein the exposed surfaces of the scattering dots are coated with reflective material.

12. The light guide plate as claimed in claim 1, further comprising the a second scattering structure formed on the light output surface, the second scattering structure comprising a plurality of scattering dots arranged on a plurality of concentric shapes around a center of the light output surface.

13. The light guide plate as claimed in claim 1, further comprising a reflector located opposite to the center;

the reflector protrudes from the light output surface to the inside of the light guide plate.

14. A light guide plate, comprising:

a body having a bottom surface having a center, a light output surface opposite to the bottom surface; and

a scattering structure formed on the light output surface, and the scattering structure comprises a plurality of scattering dots arranged in the form of a plurality of concentric shapes about the center of the light output surface.

15. A backlight module comprising:

a light guide plate including a bottom surface, a light output surface opposite to the bottom surface;

a light source located adjacent to the center of bottom surface; and

at least one scattering structure formed on the bottom surface or the light output surface, and the scattering structure comprises a plurality of scattering dots arranged in the form of a plurality of concentric shapes about the center or the center light output surface.

16. The backlight module as claimed in claim 15, further comprising a reflective plate located between the light source and the bottom surface of the light guide plate.

17. The backlight module as claimed in claim 16, wherein the reflective plate comprises a reflective film located on a surface of the reflective plate.

18. The backlight module as claimed in claim 15, further comprising a brightness enhancement film located above the light output surface of the light guide plate.

19. The backlight module as claimed in claim 15, further comprising a light scattering film located above the light output surface of the light guide plate.

20. The backlight module as claimed in claim 15, further comprising a microprism plate, a polarization plate and a diffusing plate.