Optical sheet and LCD apparatus using the same

• US 20050007513A1
• Filed: 03/03/2004
• Published: 01/13/2005
• Est. Priority Date: 03/05/2003
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Han, Byung-woong, Park, Jong-dae, Kim, Dong-hoon, Lee, Jeong-hwan, Kim, Ming-gyu
• Granted Patent: US 7,349,039 B2
• Time in Patent Office: Days
• US Class Current: 349/57
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer
• CPC Class Codes: G02B 6/0056 for producing polarisation effects, e.g. by a surface with polarizing properties or by an additional polarizing elements
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side

Abstract

The present invention relates to an optical sheet and an LCD apparatus using the same. An LCD apparatus according to the present invention comprises an LCD panel to display a picture thereon; a lamp unit emitting light; a light guide plate to guide the light from the lamp unit toward the LCD panel evenly; an optical sheet provided between the LCD panel and the light guide plate and including a condensing layer condensing the light from the light guide plate on the LCD panel, and a reflective polarizing layer attached to the surface of the condensing layer facing the LCD panel and selectively transmitting and reflecting the light condensed by the condensing layer. With this configuration, the present invention provides an optical sheet and an LCD apparatus using the same, in which a bright-line is decreased, brightness are enhanced, and the optical sheet is prevented from shrinking.

Claims

1. An optical sheet used in an LCD apparatus, comprising:

a reflective polarizing layer selectively transmitting and reflecting light; and

a condensing layer attached to one surface of the reflective polarizing layer and condensing the light.

2. The optical sheet according to claim 1, wherein the condensing layer is achieved by a plurality of prism teeth parallel arranged at intervals of a predetermined pitch.

3. The optical sheet according to claim 2, further comprising a first reinforcing layer attached to the other surface of the reflective polarizing layer and preventing the optical sheet from shrinking.

4. The optical sheet according to claim 3, wherein further comprising a second reinforcing layer provided between the reflective polarizing layer and preventing the optical sheet from shrinking.

5. The optical sheet according to claim 3, wherein on the surface of the first reinforcing layer is provided a diffusing part to diffuse the light.

6. The optical sheet according to claim 4, wherein on the surface of the first reinforcing layer is provided a diffusing part to diffuse the light.

7. The optical sheet according to claim 5, wherein the diffusing part allows the light passed through the first reinforcing layer to have a haze value of at least 30%.

8. The optical sheet according to claim 6, wherein the diffusing part allows the light passed through the first reinforcing layer to have a haze value of at least 30%.

9. The optical sheet according to claim 2, further comprising a third reinforcing layer provided between the reflective polarizing layer and the condensing layer and preventing the optical sheet from shrinking.

10. The optical sheet according to claim 2, wherein on the surface of the reflective polarizing layer is provided a diffusing part to diffuse the light.

11. The optical sheet according to claim 7, wherein on the surface of the reflective polarizing layer is provided a diffusing part to diffuse the light.

12. The optical sheet according to claim 10, wherein the diffusing part allows the light passed through the reflective polarizing layer to have a haze value of at least 30%.

13. The optical sheet according to claim 11, wherein the diffusing part allows the light passed through the reflective polarizing layer to have a haze value of at least 30%.

14. An LCD apparatus comprising an LCD panel to display a picture thereon, a lamp unit emitting light, a light guide plate to guide the light from the lamp unit toward the LCD panel evenly, the LCD comprising:

an optical sheet provided between the LCD panel and the light guide plate and including a condensing layer condensing the light from the light guide plate on the LCD panel, and a reflective polarizing layer attached to the surface of the condensing layer facing the LCD panel and selectively transmitting and reflecting the light condensed by the condensing layer.

15. The LCD apparatus according to claim 14, wherein the condensing layer of the optical sheet is achieved by a plurality of prism teeth parallel arranged at intervals of a predetermined pitch.

16. The LCD apparatus according to claim 15, further comprising a first reinforcing layer attached to the surface of the reflective polarizing layer facing the LCD panel, and preventing the optical sheet from shrinking.

17. The LCD apparatus according to claim 16, further comprising a second reinforcing layer provided between the reflective polarizing layer and preventing the optical sheet from shrinking.

18. The LCD apparatus according to claim 15, further comprising a reinforcing layer provided between the reflective polarizing layer and the condensing layer and preventing the optical sheet from shrinking.

19. The LCD apparatus according to claim 14, wherein the optical sheet is attached to the surface of the LCD panel facing the light guide plate.

20. The LCD apparatus according to claim 19, wherein on the surface of the optical sheet facing the LCD panel is provided a diffusing part to diffusing the light.

21. The LCD apparatus according to claim 20, wherein the diffusing part of the optical sheet allows the light passed through the optical sheet to have a haze value of at least 30%.

22. The LCD apparatus according to claim 15, wherein the prism teeth of the optical sheet are formed along a transmitting axis direction of the reflective polarizing layer.

23. The LCD apparatus according to claim 22, wherein on the opposite surface of the light guide plate facing the LCD panel is provided a plurality of prism teeth parallel arranged at intervals of a predetermined pitch, and the prism teeth of the light guide plate are perpendicular to the prism teeth of the optical sheet.