Rear projection screens

• US 4,053,208 A
• Filed: 02/03/1976
• Issued: 10/11/1977
• Est. Priority Date: 02/03/1975
• Status: Expired due to Term

• Current Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Kato, Hisatoyo, Miyahara, Junji
• Primary Examiner(s): Wintercorn, Richard A.
• Application Number:
  US05/654,830
• Time in Patent Office: 616 Days
• Field of Search: 350/117, 350/128, 350/126, 350/156, 350/276 R, 240/41.4 R, 240/41.4 D, 178/7.82, 178/7.85, 313/112
• US Class Current: 359/460
• CPC Class Codes: G03B 21/625 Lenticular translucent screens

Abstract

A rear projection screen produced by providing surface irregularity directly on at least one side of a light diffusion layer containing at least one light scattering material selected from the group consisting of one or more waxes, one or more crystalline polymers or a mixture thereof.

Claims

1. A rear projection screen comprising a diffusion layer containing at least one light scattering material selected from the group consisting of wax and crystalline polymers wherein a micro-optical surface irregularity is provided directly on at least one side of said diffusion layer.

2. The rear projection screen according to claim 1, wherein the wax is selected from the group consisting of natural wax, and petroleum wax.

3. The rear projection screen according to claim 1, wherein the crystalline polymer is selected from the group consisting of polyolefins, polystyrenes, polycarbonates, polyesters, polyamides, polyurethanes, polyvinyl alcohols, esters, and ethers.

4. The rear projection screen according to claim 1, wherein the diffusion layer composed of wax further contains a wax reforming agent.

5. The rear projection screen according to claim 4, wherein the wax reforming agent is selected from the group consisting of natural resins and synthetic resins.

6. The rear projection screen according to claim 4, wherein the wax reforming agent is selected from the group consisting of an ethylene-vinyl acetate copolymer, polyisobutylene, polybutene, rosin, and atactic polypropylene.

7. The rear projection screen according to claim 4, wherein the wax reforming agent is added in an amount of 0.1 to 20% by weight of the total weight of the wax and additives.

8. The rear projection screen according to claim 1, wherein the surface irregularity comprises a micro-optical element structure.

9. The rear projection screen according to claim 8, wherein the size of each micro-optical element as a pitch ranges between about 0.05 and about 2 mm.

10. The rear projection screen according to claim 8, wherein the surface irregularity is a Fresnel lens structure.

11. The rear projection screen according to claim 8, wherein the surface irregularity is a lenticular lens structure.

12. The rear projection screen according to claim 8, wherein the surface irregularity is a V groove structure.

13. The rear projection screen according to claim 1, wherein a Fresnel lens structure is provided on one side of the diffusion layer and a lenticular lens structure is provided on the other side.

14. The rear projection screen according to claim 1, wherein the diffusion layer is bonded to a transparent support.

15. The rear projection screen according to claim 14, wherein the transparent support is an acrylic resin plate.

16. The rear projection screen according to claim 1, wherein the wax is a synthetic wax.

17. The rear projection screen according to claim 16, wherein the molecular weight of the synthetic wax is not more than about 5,000, and the melt index of the synthetic wax is not less than about 1,000.

18. The rear projection screen according to claim 1, wherein the thickness of the diffusion plate ranges between about 0.1 mm and 10 mm.

19. The rear projection screen according to claim 16, wherein the thickness of the diffusion plate ranges between 0.1 mm and 10 mm.

20. The rear projection screen according to claim 8 wherein the surface irregularity consists essentially of a micro-optical element.

21. The rear projection screen according to claim 8 wherein the surface irregularity consists of a micro-optical element.