POLARIZATION LIGHT SPLITTING FILM, BACKLIGHT SYSTEM AND LIQUID CRYSTAL DISPLAY

• US 20020003593A1
• Filed: 02/17/1998
• Published: 01/10/2002
• Est. Priority Date: 02/18/1997
• Status: Active Grant

• Current Assignee: Dai Nippon Printing Company Limited
• Original Assignee: Dai Nippon Printing Company Limited
• Inventors: ARAKAWA, FUMIHIRO, KASHIMA, KEIJI
• Granted Patent: US 6,559,911 B2
• Time in Patent Office: Days
• US Class Current: 349/65
• CPC Class Codes: G02B 5/3016 involving passive liquid crystal elements optical properties of liquid crystals G02F1/0063; polarising elements associated with active liquid crystal devices G02F1/133528
• CPC Class Codes: G02F 1/133502 Antiglare, refractive index matching layers
• CPC Class Codes: G02F 1/133504 Diffusing, scattering, diffracting elements associated to illuminating devices G02F1/133606
• CPC Class Codes: G02F 1/133526 Lenses, e.g. microlenses or Fresnel lenses
• CPC Class Codes: G02F 1/133536 Reflective polarizers G02F1/13362 takes precedence
• CPC Class Codes: G02F 1/133543 Cholesteric polarisers
• CPC Class Codes: G02F 1/133607 the light controlling member including light directing or refracting elements, e.g. prisms or lenses
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side
• CPC Class Codes: G02F 1/13362 providing polarized light, e.g. by converting a polarisation component into another one
• CPC Class Codes: G02F 1/133638 Waveplates, i.e. plates with a retardation value of lambda/n
• CPC Class Codes: G02F 2201/343 cholesteric liquid crystal reflector

Abstract

A polarization light splitting film having a light receiving side and a light transmitting side. The polarization light splitting film includes an optical rotation selection layer at the light receiving side for reflecting one of right and left circularly polarized components of a light beam that is incident on the light receiving side and for transmitting the other one of the right and left circular polarization components of the light beam, and a quarter-wave layer laminated over the optical rotation selection layer at the light transmitting side.

Claims

1. A polarization light splitting film having a light receiving side and a light transmitting side, the polarization light splitting film comprising:

an optical rotation selection layer at the light receiving side for reflecting one of right and left circularly polarized components of a light beam that is incident on the light receiving side and for transmitting the other one of the right and left circular polarization components of the light beam; and

a quarter-wave layer laminated over the optical rotation selection layer at the light transmitting side.

2. The polarization light splitting film according to claim 1, further comprising a diffusion layer laminated under the optical rotation selection layer at the light receiving side.

3. The polarization light splitting film according to claim 2, further comprising a prism layer at the light receiving side for deflecting the incident light beam.

4. The polarization light splitting film according to claim 2, further comprising a lens layer at the light receiving side for one of converging and diverging the incident light beam.

5. The polarization light splitting film according to claim 1, wherein the optical rotation selection layer includes a base member and a cholesteric liquid crystal layer laminated on the base member.

6. The polarization light splitting film according to claim 5, further comprising a diffusion layer laminated under the optical rotation selection layer at the light receiving side.

7. The polarization light splitting film according to claim 6, further comprising a prism layer at the light receiving side for deflecting the incident light beam.

8. The polarization light splitting film according to claim 6, further comprising a lens layer at the light receiving side for one of converging and diverging the incident light beam.

9. The polarization light splitting film according to claim 5, further comprising a prism layer at the light receiving side for deflecting the incident light beam.

10. The polarization light splitting film according to claim 5, further comprising a lens layer at the light receiving side for one of converging and diverging the incident light beam.

11. The polarization light splitting film according to claim 1, further comprising a prism layer at the light receiving side for deflecting the incident light beam.

12. The polarization light splitting film according to claim 1, further comprising a lens layer at the light receiving side for one of converging and diverging the incident light beam.

13. The polarization light splitting film according to claim 1, further comprising an anti-reflection layer at the light receiving side.

14. The polarization light splitting film according to claim 1, further comprising a linear polarizing layer laminated at the light transmitting side.

15. A backlight system comprising:

a polarization light splitting film having a light receiving side and a light transmitting side, the polarization light splitting film including;

an optical rotation selection layer at the light receiving side for reflecting one of right and left circularly polarized components of a light beam that is incident on the light receiving side and for transmitting the other one of the right and left circular polarization components of the light beam; and

a quarter-wave layer laminated over the optical rotation selection layer at the light transmitting side;

a light source for emitting a light beam; and

a light guide disposed at the light receiving side of the polarization light splitting film for guiding the light beam emitted from the light source towards the polarization light splitting film as the incident light.

16. The backlight system according to claim 15, wherein the polarization light splitting film further includes a diffusion layer laminated under the optical rotation selection layer at the light receiving side.

17. The backlight system according to claim 16, wherein the polarization light splitting film further includes a prism layer at the light receiving side for deflecting the incident light beam.

18. The backlight system according to claim 16, wherein the polarization light splitting film further includes a lens layer at the light receiving side for one of converging and diverging the incident light beam.

19. The backlight system according to claim 15, wherein the optical rotation selection layer includes a base member and a cholesteric liquid crystal layer laminated on the base member.

20. The backlight system according to claim 19, wherein the polarization light splitting film further includes a diffusion layer laminated under the optical rotation selection layer at the light receiving side.

21. The backlight system according to claim 20, wherein the polarization light splitting film further includes a prism layer at the light receiving side for deflecting the incident light beam.

22. The backlight system according to claim 20, wherein the polarization light splitting film further includes a lens layer at the light receiving side for one of converging and diverging the incident light beam.

23. The backlight system according to claim 19, wherein the polarization light splitting film further includes a prism layer at the light receiving side for deflecting the incident light beam.

24. The backlight system according to claim 19, wherein the polarization light splitting film further includes a lens layer at the light receiving side for one of converging and diverging the incident light beam.

25. The backlight system according to claim 15, wherein the polarization light splitting film further includes a prism layer at the light receiving side for deflecting the incident light beam.

26. The backlight system according to claim 15, wherein the polarization light splitting film further includes a lens layer at the light receiving side for one of converging and diverging the incident light beam.

27. The backlight system according to claim 15, wherein the polarization light splitting film further includes an anti-reflection layer at the light receiving side.

28. The backlight system according to claim 15, wherein the polarization light splitting film further includes a linear polarizing layer laminated at the light transmitting side.

29. The backlight system according to claim 15, further comprising a reflection plate for reflecting the one of the right and left circular polarization components of the light beam reflected from the optical rotation selection layer.

30. A liquid crystal display device comprising:

a polarization light splitting film having a light receiving side and a light transmitting side, the polarization light splitting film including an optical rotation selection layer at the light receiving side for reflecting one of right and left circularly polarized components of a light beam that is incident on the light receiving side and for transmitting the other one of the right and left circular polarization components of the light beam, the polarization light splitting film further including a quarter-wave layer laminated over the optical rotation selection layer at the light transmitting side;

a light source for emitting a light beam;

a light guide disposed at the light receiving side of the polarization light splitting film for guiding the light beam emitted from the light source towards the polarization light splitting film as the incident light; and

a liquid crystal cell receiving the light transmitted from the polarization light splitting film in order to display at least one image.

31. The liquid crystal display device according to claim 30, wherein the polarization light splitting film further includes a diffusion layer laminated under the optical rotation selection layer at the light receiving side.

32. The liquid crystal display device according to claim 31, wherein the polarization light splitting film further includes a prism layer at the light receiving side for deflecting the incident light beam.

33. The liquid crystal display device according to claim 31, wherein the polarization light splitting film further includes a lens layer at the light receiving side for one of converging and diverging the incident light beam.

34. The liquid crystal display device according to claim 30, wherein the optical rotation selection layer includes a base member and a cholesteric liquid crystal layer laminated on the base member.

35. The liquid crystal display device according to claim 34, wherein the polarization light splitting film further includes a diffusion layer laminated under the optical rotation selection layer at the light receiving side.

36. The liquid crystal display device according to claim 35, wherein the polarization light splitting film further includes a prism layer at the light receiving side for deflecting the incident light beam.

37. The liquid crystal display device according to claim 35, wherein the polarization light splitting film further includes a lens layer at the light receiving side for one of converging and diverging the incident light beam.

38. The liquid crystal display device according to claim 34, wherein the polarization light splitting film further includes a prism layer at the light receiving side for deflecting the incident light beam.

39. The liquid crystal display device according to claim 34, wherein the polarization light splitting film further includes a lens layer at the light receiving side for one of converging and diverging the incident light beam.

40. The liquid crystal display device according to claim 30, wherein the polarization light splitting film further includes a prism layer at the light receiving side for deflecting the incident light beam.

41. The liquid crystal display device according to claim 30, wherein the polarization light splitting film further includes a lens layer at the light receiving side for one of converging and diverging the incident light beam.

42. The liquid crystal display device according to claim 30, wherein the polarization light splitting film further includes an anti-reflection layer at the light receiving side.

43. The liquid crystal display device according to claim 30, wherein the polarization light splitting film further includes a linear polarizing layer laminated at the light transmitting side.

44. The liquid crystal display device according to claim 30, further comprising a reflection plate for reflecting the one of the right and left circular polarization components of the light beam reflected from the optical rotation selection layer.