Backlight module and liquid crystal display device using the same

• US 20060114689A1
• Filed: 11/28/2005
• Published: 06/01/2006
• Est. Priority Date: 11/26/2004
• Status: Active Grant

• Current Assignee: InnoLux Corporation
• Original Assignee: Innolux Display Corporation (InnoLux Corporation)
• Inventors: Yao, Yen-Chang, Chang, Chih Ching
• Granted Patent: US 7,377,682 B2
• Time in Patent Office: Days
• US Class Current: 362/561
• CPC Class Codes: G02B 6/0091 of the light source relative to the light guide G02B6/0021 takes precedence

Abstract

A backlight module includes a frame (55) including a spring element (556), a light guide plate (56) disposed in the frame including an incident surface (561), and a radiation element (59) being pressed onto the incident surface by the spring element. The spring element presses the radiation elements against the light guide plate, and thereby decreases the distance and angle between the radiation elements and the light guide plate. This improves the brightness and uniformity of the emitting luminance of the backlight module.

Claims

1. A backlight module, comprising:

a frame comprising one or more spring arms;

a light guide plate disposed in the frame and comprising an incident surface; and

one or more radiation elements pressed against the incident surface by corresponding spring arms.

2. The backlight module as claimed in claim 1, further comprising a printed circuit board, wherein the radiation elements are arranged on the printed circuit board.

3. The backlight module as claimed in claim 2, wherein the frame comprises a side wall, and the spring arms extend from an inside of the side wall.

4. The backlight module as claimed in claim 3, wherein each of the spring arms comprises a partition and a spring arm extending from the partition, the spring arm is curved, and the spring arm is oriented generally perpendicular to the partition.

5. The backlight module as claimed in claim 3, wherein a plurality of protrusions extends from the inside of the side wall of the frame, and the protrusions and the spring arms define an interspace therebetween for receiving at least a part of the printed circuit board therein.

6. The backlight module as claimed in claim 1, further comprising one or more optical films arranged on the emitting surface of the light guide plate.

7. The backlight module as claimed in claim 6, wherein the optical films comprise any one or more of a diffusion plate and a brightness enhancement film.

8. The backlight module as claimed in claim 2, wherein the printed circuit board is a flexible printed circuit board.

9. The backlight module as claimed in claim 1, wherein the radiation elements are one or more light emitting diodes.

10. A liquid crystal display device, comprising:

a backlight module and a liquid crystal display panel;

wherein the backlight module comprises;

a frame having spring arms;

a light guide plate disposed in the frame and having an incident surface; and

one or more radiation elements being pressed against the incident surface by corresponding spring arms.

11. The liquid crystal display device as claimed in claim 10, further comprising a printed circuit board, wherein the radiation elements are arranged on the printed circuit board.

12. The liquid crystal display device as claimed in claim 11, wherein the frame comprises a side wall, and the spring arms extend from the sidewall toward the inside of the frame.

13. The liquid crystal display device as claimed in claim 12, wherein one of the spring arms extend from each of the arms, the spring arms are arc-shaped, and the spring arms are arranged substantially perpendicular to the corresponding arms.

14. The liquid crystal display device as claimed in claim 12, further comprising a supporting bar extending toward the inside of the frame, and the arm and the bar define an interspace which can fix one side edge of the printed circuit board.

15. The liquid crystal display device as claimed in claim 10, further comprising optical films which are arranged on the emitting surface of the light guide plate.

16. The liquid crystal display device as claimed in claim 15, wherein the optical films comprise a diffusion plate or a brightness enhancement film.

17. The liquid crystal display device as claimed in claim 11, wherein the printed circuit board is a flexible printed circuit board.

18. The liquid crystal display device as claimed in claim 10, wherein the radiation elements are light emitting diodes.