OPTICAL DIFFUSING SHEET, OPTICAL DEFLECTING SHEET, AND TRANSMISSION TYPE SCREEN

• US 20090190211A1
• Filed: 01/11/2006
• Published: 07/30/2009
• Est. Priority Date: 01/11/2005
• Status: Active Grant

• Current Assignee: Dai Nippon Printing Company Limited
• Original Assignee: Dai Nippon Printing Company Limited
• Inventors: Kato, Kei, Kashiwagi, Tsuyoshi, Kodama, Daijiro
• Granted Patent: US 7,885,003 B2
• Time in Patent Office: Days
• US Class Current: 359/457
• CPC Class Codes: G02B 5/0242 by means of dispersed particles
• CPC Class Codes: G02B 5/0278 used in transmission
• CPC Class Codes: G03B 21/625 Lenticular translucent screens

Abstract

An optical diffusing sheet is provided, which prevents deterioration in image quality which might result from warping of the sheets due to environmental changes, and is capable of, even if a substrate is broken by an accident, preventing scattering of pieces of the broken substrate. An optical diffusing sheet is used in a transmission type screen that emits imaging light projected from an incident side to an emergent side. The optical diffusing sheet includes a highly rigid substrate layer with a light-transmissibility and a high rigidity, and a plurality of layers laminated on the highly rigid substrate layer. The plurality of layers includes at least a pair of anti-scattering layers disposed on opposite sides of the highly rigid substrate layer for preventing scattering of the highly rigid substrate layer. At least one layer of the two or more layers includes an optical diffusing element that diffuses imaging light.

Claims

1. An optical diffusing sheet for use in a transmission type screen that emits imaging light projected from an incident side to an emergent side, comprising:

a highly rigid substrate layer with a light-transmissibility and a high rigidity; and

two or more layers laminated on the highly rigid substrate layer, the layers including at least a pair of anti-scattering layers disposed on opposite sides of the highly rigid substrate layer for preventing scattering of the high rigid substrate layer;

wherein at least one layer of the two or more layers includes an optical diffusing element that diffuses imaging light.

2. The optical diffusing sheet according to claim 1, wherein

the highly rigid substrate layer is formed of glass or translucent ceramic.

3. The optical diffusing sheet according to claim 1, wherein

the optical diffusing element is a lenticular lens that is formed by arranging a plurality of unit optical shape portions each having a refracting surface that refracts at least a part of imaging light incident thereon.

4. The optical diffusing sheet according to claim 1, wherein

the optical diffusing element is formed by arranging a plurality of unit optical shape portions each having a total reflecting surface that totally reflects at least a part of imaging light incident thereon.

5. The optical diffusing sheet according to claim 1, wherein

at least one layer of the two or more layers has a diffusing part that diffuses light.

6. The optical diffusing sheet according to claim 5, wherein

at least one layer of the two or more layers that is laminated on a position closer to the incident side than the highly rigid substrate layer, and at least one layer of the two or more layers that is laminated on a position closer to the emergent side than the highly rigid substrate layer, have the diffusing parts, respectively.

7. The optical diffusing sheet according to claim 1, wherein:

at least one layer of the two or more layers has a first optical diffusing element formed by arranging along one direction a plurality of unit optical shape portions each having a refracting surface that refracts at least a part of imaging light incident thereon or a total reflecting surface that totally reflects at least a part of imaging light incident thereon; and

another layer different from the one layer of the two or more layers has a second optical diffusing element formed by arranging the plurality of unit optical shape portions along the other direction substantially perpendicular to the one direction.

8. The optical diffusing sheet according to claim 1, wherein

at least one layer of the anti-scattering layers has at least one of the following functions:

diffusing function, anti-reflection function, anti-glaring function, coloring function, dimmer function, ultraviolet absorption function, antistatic function, soil-resistant function, sensing function, or hard-coating function.

9. The optical diffusing sheet according to claim 1, wherein

the two or more layers includes a joining layer that is interposed between the highly rigid substrate layer and the anti-scattering layer so as to join the highly rigid substrate layer and the anti-scattering layer to each other;

and

the joining layer includes at least one of a diffusing agent for diffusing light and an ultraviolet absorbing agent for absorbing ultraviolet light.

20. A transmission type screen comprising the optical diffusing sheet according to claim 1.

21. The transmission type screen according to claim 20, wherein

at least one layer of the two or more layers has a first optical diffusing element formed by arranging along one direction a plurality of unit optical shape portions each having a refracting surface that refracts at least a part of imaging light incident thereon or a total reflecting surface that totally reflects at least a part of imaging light incident thereon;

another layer different from the one layer of the two or more layers has a second optical diffusing element formed by arranging the plurality of unit optical shape portions along the other direction substantially perpendicular to the one direction.

22. The transmission type screen according to claim 20, further comprising an optical deflecting sheet comprising:

a highly rigid substrate layer with a light-transmissibility and a high rigidity; and

two or more layers laminated on the highly rigid substrate layer, the layers including at least a pair of anti-scattering layers disposed on opposite sides of the highly rigid substrate layer for preventing scattering of the highly rigid substrate layer;

wherein at least one layer of the two or more layers includes an optical deflecting element that deflects imaging light by refracting or reflecting the imaging light.

10. An optical deflecting sheet for use in a transmission type screen that emits imaging light projected from an incident side to an emergent side, comprising:

a highly rigid substrate layer with a light-transmissibility and a high rigidity; and

two or more layers laminated on the highly rigid substrate layer, the layers including at least a pair of anti-scattering layers disposed on opposite sides of the highly rigid substrate layer for preventing scattering of the highly rigid substrate layer;

wherein at least one layer of the two or more layers includes an optical deflecting element that deflects imaging light by refracting or reflecting the imaging light.

11. The optical deflecting sheet according to claim 10, wherein

the highly rigid substrate layer is formed of glass or translucent ceramic.

12. The optical deflecting sheet according to claim 10, wherein

the optical deflecting element is a Fresnel lens.

13. The optical deflecting sheet according to claim 10, wherein

the optical deflecting element is a prism part formed by arranging a plurality of unit prisms each having an incident surface on which light is incident and a total reflecting surface for reflecting at least a part of light incident on the incident surface.

14. The optical deflecting sheet according to claim 13, wherein

at least one layer of the two or more layers includes an optical diffusing element that diffuses imaging light incident thereon.

15. The optical deflecting sheet according to claim 14, wherein

the optical diffusing element is formed by arranging a plurality of unit optical shape portions each having a total reflecting surface that totally reflects at least a part of imaging light incident thereon.

16. The optical deflecting sheet according to claim 10, wherein

at least one layer of the two or more layers has a first optical diffusing element formed by arranging along one direction a plurality of unit optical shape portions each having a refracting surface that refracts at least a part of imaging light incident thereon or a total reflecting surface that totally reflects at least a part of imaging light incident thereon;

and

another layer different from the one layer of the two or more layers has a second optical diffusing element formed by arranging the plurality of unit optical shape portions along the other direction substantially perpendicular to the one direction.

17. The optical deflecting sheet according to claim 10, wherein

at least one layer of the two or more layers has a diffusing part that diffuses light.

18. The optical deflecting sheet according to claim 17, wherein

at least one layer the two or more layers that is laminated on a position closer to the incident side than the highly rigid substrate layer, and at least one layer of the two or more layers that is laminated on a position closer to the emergent side than the highly rigid substrate layer, have the diffusing parts, respectively.

19. The optical deflecting sheet according to claim 10, wherein

the two or more layers includes a joining layer that is interposed between the highly rigid substrate layer and the anti-scattering layer so as to join the highly rigid substrate layer and the anti-scattering layer to each other;

and

the joining layer includes at least one of a diffusing agent for diffusing light and an ultraviolet absorbing agent for absorbing ultraviolet light.

23. A transmission type screen comprising the optical deflecting screen according to claim 10.