Backlight module with transflective layer at light source

• US 20050201077A1
• Filed: 01/31/2005
• Published: 09/15/2005
• Est. Priority Date: 03/09/2004
• Status: Abandoned Application

• Current Assignee: Hon Hai Precision Industry Co., Ltd.
• Original Assignee: Hon Hai Precision Industry Co., Ltd.
• Inventors: Tsai, Kun-Jung
• Application Number:
  US11/046,955
• Publication Number:
  US 20050201077A1
• Time in Patent Office: Days
• US Class Current: 362/26
• CPC Class Codes: G01D 11/28 Structurally-combined illuminating devices
• CPC Class Codes: G02B 6/0021 for housing at least a part of the light source, e.g. by forming holes or recesses
• CPC Class Codes: G02B 6/0031 Reflecting element, sheet or layer

Abstract

A backlight module (20) includes a light guide plate (20), a light source (21), and a translective film (22). The light guide plate includes a bottom surface (26) and an opposite light emitting surface (25). A recess (27) is defined in the light guide plate at the bottom surface, and contains the light source. The transflective element is disposed between the light source and the recess, to control the intensity of the light beams entering the light guide plate. The transfective film negates excessively high intensity of light beams at regions near the light source. Thus the backlight module provides uniform illumination.

Claims

1. A backlight module, comprising:

a light source;

a light guide plate comprising a bottom surface and an opposite light emitting surface, and a receptacle at the bottom surface containing the light source; and

a transflective element disposed in the receptacle between the light source and the light guide plate, for reducing the intensity of light beams entering the light guide plate thereat.

2. The backlight module as recited in claim 1, wherein the transflective element has different reflection ratios at different portions thereof.

3. The backlight module as recited in claim 2, wherein a reflection ratio of the transflective element progressively decreases with increasing distance away from a position thereof directly above the light source.

4. The backlight module as recited in claim 1, wherein the receptacle comprises a recess, and a portion of the light guide plate at an inmost end of the recess is boss-shaped.

5. The backlight module as recited in claim 1, wherein receptacle comprises a through hole.

6. The backlight module as recited in claim 1, further comprising a dot pattern formed on the bottom surface of the light guide plate.

7. The backlight module as recited in claim 1, further comprising a diffusion plate disposed adjacent the light emitting surface.

8. The backlight module as recited in claim 1, further comprising a reflection plate disposed adjacent the bottom surface of the light guide plate.

9. The backlight module as recited in claim 8, wherein the transflective element has different reflection ratios at different portions thereof.

10. The backlight module as recited in claim 9, wherein a reflection ratio of the transflective element progressively decreases with increasing distance away from a position thereof directly above the light source.

11. The backlight module as recited in claim 8, wherein the receptacle comprises a recess, and a portion of the light guide plate at an inmost end of the recess is boss-shaped.

12. The backlight module as recited in claim 8, wherein receptacle comprises a through hole.

13. The backlight module as recited in claim 8, further comprising a dot pattern formed on the bottom surface of the light guide plate.

14. The backlight module as recited in claim 8, further comprising a diffusion plate disposed adjacent the light emitting surface.

15. A backlight module, comprising:

a light source;

a light guide member disposed next to said light source, and comprising a surface to accept light from said light source into said light guide member and a light emitting surface for emitting said light out of said light guide member; and

a transflective element disposed between said light source and said light emitting surface of said light guide member so as to proportionally reduce intensity of said light transmitted from said light source to a projective portion of said light source on said light emitting surface.

16. The backlight module as recited in claim 15, wherein said transflective element is a transflective film attached to said surface of said light guide member for accepting said light from said light source.

17. The backlight module as recited in claim 15, wherein said light guide member comprises a boss-shaped portion disposed between said transflective element and said light emitting surface to control transmission directions of said light after said light encounters said transflective element.

18. A backlight module, comprising:

a light guide member comprising a surface to accept light transmitted into said light guide member and a light emitting surface for emitting said light out of said light guide member;

a light source used to provide said light toward said light guide member, said light source located next to a portion of said light guide member where a distance between said light source and said light emitting surface is shorter than thickness of other portions of said light guide member; and

a transflective element disposed between said light source and said light emitting surface of said light guide member so as to reduce intensity of said light passing through said transflective element.

19. The backlight module as recited in claim 18, wherein said transflective element is a transflective film attached to said surface of said light guide member for accepting said light of said light source.

20. The backlight module as recited in claim 19, wherein said transflective element and said light source are received in a recess of said light guide member.