FRONT LIGHT MODULE AND DISPLAY MODULE

• US 20160223734A1
• Filed: 01/07/2016
• Published: 08/04/2016
• Est. Priority Date: 01/14/2015
• Status: Active Grant

• Current Assignee: E Ink Holdings Incorporated
• Original Assignee: E Ink Holdings Incorporated
• Inventors: Hsu, Chin-Ju, Pao, Yu-Nan, Chen, I-Jeng, Tai, Sheng-Chieh, Huang, Hsin-Tao
• Granted Patent: US 10,416,367 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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: G02B 6/0073 Light emitting diode [LED]

Abstract

A front light module including a light guide plate and a light source is provided. The light guide plate includes a first surface, a second surface and a light entering surface. The second surface is opposite the first surface. The light entering surface has at least one area that is adjacent to the first surface and the second surface. The light source is disposed beside the light entering surface and is configured to illuminate the light guide plate. The at least one area and an optical axis of the light source form a first angle. The first angle is less than 90 degrees. A display module is also provided.

Claims

1. A front light module, comprising:

a light guide plate, comprising;

a first surface;

a second surface opposite the first surface; and

a light entering surface having an area adjacent to the first surface and the second surface; and

a light source disposed beside the light entering surface and configured to illuminate the light guide plate, wherein the area and an optical axis of the light source form a first angle less than 90 degrees.

2. The front light module of claim 1, wherein the first angle ranges from 50 to 85 degrees.

3. The front light module of claim 1, wherein the second surface is parallel to the optical axis of the light source, the light entering surface and the second surface form a second angle ranging from 50 to 85 degrees.

4. The front light module of claim 3, wherein the first surface and the second surface are substantially parallel to each other.

5. The front light module of claim 1, wherein the light source is a light-emitting diode (LED).

6. The front light module of claim 1, wherein the light entering surface is a plane.

7. The front light module of claim 1, wherein the light entering surface comprises a first microstructure protruding from or recessed into the light entering surface, and the first microstructure comprises the area.

8. The front light module of claim 7, wherein the first microstructure has a shape of a portion of a cylinder, a portion of a prism or a portion of a cone.

9. The front light module of claim 8, wherein the light entering surface further comprises a second microstructure protruding from or recessed into the light entering surface, and the first microstructure and the second microstructure are alternately arranged in a row, wherein the first microstructure has a shape of a portion of a cone, a vertex of the cone being connected to the first surface and a bottom surface of the cone being connected to the second surface, the second microstructure has a shape of a portion of a cone, a vertex of the cone being connected to the second surface and a bottom surface of the cone being connected to the first surface.

10. The front light module of claim 7, wherein the first microstructure is a plurality of first microstructures connected or not connected to one another.

11. A display module, comprising:

a reflective display panel;

a light guide plate disposed on the reflective display panel, the light guide plate comprising;

a first surface;

a second surface opposite the first surface, wherein one of the first surface and the second surface faces the reflective display panel and the other faces away from the reflective display panel; and

a light entering surface having an area adjacent to the first surface and the second surface; and

a light source disposed beside the light entering surface and configured to illuminate the light guide plate, wherein the area and an optical axis of the light source form a first angle less than 90 degrees.

12. The display module of claim 11, wherein the first angle ranges from 50 to 85 degrees.

13. The display module of claim 11, wherein the second surface is parallel to the optical axis of the light source, and the light entering surface and the second surface form a second angle ranging from 50 to 85 degrees.

14. The display module of claim 13, wherein the first surface and the second surface are substantially parallel to each other.

15. The display module of claim 11, wherein the light entering surface is a plane.

16. The display module of claim 11, wherein the light entering surface comprises a first microstructure protruding from or recessed into the light entering surface, and the first microstructure comprises the area.

17. The display module of claim 16, wherein the first microstructure has a shape of a portion of a cylinder, a portion of a prism or a portion of a cone.

18. The display module of claim 17, wherein the light entering surface further comprises a second microstructure protruding from or recessed into the light entering surface, and the first microstructure and the second microstructure are alternately arranged in a row, wherein the first microstructure has a shape of a portion of a cone, a vertex of the cone being connected to the first surface and a bottom surface of the cone being connected to the second surface, the second microstructure has a shape of a portion of a cone, a vertex of the cone being connected to the second surface and a bottom surface of the cone being connected to the first surface.

19. The display module of claim 16, wherein the first microstructure is a plurality of first microstructures connected or not connected to one another.

20. The display module of claim 11, further comprising an adhesive layer disposed between the reflective display panel and the light guide plate and configured to fix the reflective display panel and the light guide plate, wherein the adhesive layer has a refractive index smaller than that of the light guide plate.

21. The display module of claim 20, wherein the one of the first surface and the second surface that faces the reflective display panel comprises a plurality of microstructures protruding from or recessed into the one of the first surface and the second surface.