PROJECTION SCREEN

• US 3,844,644 A
• Filed: 09/19/1973
• Issued: 10/29/1974
• Est. Priority Date: 09/19/1973
• Status: Expired due to Term

• Current Assignee: Eugene Martinez
• Original Assignee: Eugene Martinez
• Inventors: Martinez, Eugene
• Primary Examiner(s): Matthews, Samuel S.
• Assistant Examiner(s): Mathews, Alan
• Application Number:
  US05/398,883
• Time in Patent Office: 405 Days
• Field of Search: 350/117,126,127,128,129,124 117/11,47A 161/4,117,214,216
• US Class Current: 359/443
• CPC Class Codes: G03B 21/60 characterised by the nature of the surface
• CPC Class Codes: Y10T 24/4406 Resilient channel or bar
• CPC Class Codes: Y10T 428/24364 with transparent or protective coating
• CPC Class Codes: Y10T 428/24537 Parallel ribs and/or grooves
• CPC Class Codes: Y10T 428/24545 Containing metal or metal compound

Abstract

This is a material developed for use as a front surface projection screen. It consists of three elements: the first being a milky white translucent plastic film, the second being very fine '"'"''"'"''"'"''"'"'hairline'"'"''"'"''"'"''"'"' striations on the back surface (that which is opposite the surface nearest to the projection source) of the film in a random pattern evenly covering the entire surface and the third element is a highly reflective metallized coating (vacuum plated aluminum) on the back surface. The purpose of the first element is to provide a matte white surface on which an image can be formed by the light projected onto it from the projection source, the fact that it is translucent rather than opaque allows the second and third elements to function as follows. The striations on the back surface of the film serve to disperse the reflected cone of light in a wide horizontal angle (approximately 110* ) and a narrow vertical angle (approximately 30* ). The purpose of the reflective coating on the back surface is to return more of the light projected to the film than would be returned if the film were an opaque white material. The screen material can be used in a number of different ways such as the traditional roll-up screens, grommeted along the edges and laced to a frame made of tubing, or utilizing any suitable rigid frame that holds the screen in a flat panel presenting a soft surface (if you push it with a finger, it dimples and returns to flat), or in any other suitable manner either flat or curved or any other shape. It is desirable that in use the screen be kept as flat as possible in order to provide an undistorted projection surface.

Claims

1. A FRONT SURFACE PHOTOGRAPHIC PROJECTION SCREEN COMPRISING A MILKY WHITE TRANSLUCENT PLASTIC FILM HAVING A FRONT SURFACE TO FACE THE PROJECTION SOURCE, THE REAR SURFACE OF SAID FILM BEING FORMED WITH FINE STRIATIONS IN A RANDOM PATTERN SUBSTANTIALLY COVERING SAID REAR SURFACE;

AND A REFLECTIVE METALLIZED DEPOSITED COATING FORMED ON SAID STRIATED REAR SURFACE;

THE REAR SURFACE OF SAID METALLIZED COATING FORMING THE REAR SURFACE OF SAID SCREEN, SAID FILM ALLOWING PROJECTED RAYS TO PASS THROUGH SAID FILM TO BE REFLECTED BACK THROUGH THE FILM BY SAID COATING AND SAID FILM ALSO CARRYING THE IMAGE CAUSED BY SAID RAYS PASSING THERETHROUGH WHILE SAID RAYS ARE PROJECTED ONTO SAID FRONT SURFACE.

2. The projection screen of claim 1, wherein said plastic film comprises finely divided evenly dispersed particulates.

3. The projection screen of claim 1, wherein said plastic film has a thickness of from about 0.001 inch to about 0.005 inch.

4. The projection screen of claim 1, wherein said reflective metallized coating is vacuum deposited aluminum.

5. The projection screen of claim 1, wherein said plastic film comprises a polyesteR film.

6. The projection screen of claim 1, wherein said plastic film comprises a polyvinyl film.

7. The projection screen of claim 2, wherein said finely divided, evenly dispersed particulates is a white pigmenting agent imparting a milky-white appearance to the plastic film.

8. The projection screen of claim 2, wherein said plastic film is a thermoplastic film and wherein said particulates are incorporated in thermoforming the film.

9. The projection screen of claim 1, said film being flexible.

10. The combination of claim 1, said rear surface of said metallized coating being unbacked.

11. The projection screen of claim 1, said translucent plastic film having a light transmission of from about 60 percent to about 75 percent.

12. The projection screen of claim 1, in combination with a photographic projection source directing light rays to said front surface.

13. The combination of claim 12, and a supporting frame for said screen having a front side and a rear side and means to mount said screen on said frame with the front surface of said film facing in the same direction as the front side of said frame, and with said screen having a flat soft panel.

14. The combination of claim 1, and a frame having a front side and a rear side, and means to mount said screen on said frame, with the front surface of said film facing in the same direction as said front side of said frame and said screen presenting a soft flat panel.

15. A front surface photographic projection screen comprising a milky white translucent plastic film having a front surface to face the projection source, and a reflective metallized deposited coating on the rear surface of said screen, said film allowing projected rays to pass through said film to be reflected back through the film by said coating and said film also carrying the image caused by the rays passing therethrough while the rays are projected onto said front surface.

16. The combination of claim 15, wherein said plastic film comprises finely divided evenly dispersed particulates.

17. The combination of claim 16, said plastic film has a thickness of about 0.001 inch to about 0.005 inch.

18. The combination of claim 17, wherein said reflective metallized coating is vacuum deposited aluminum.

19. The combination of claim 18, wherein said plastic film comprises a polyester film.

20. The combination of claim 18, wherein said plastic film comprises a polyvinyl film.

21. The combination of claim 16, wherein said finely divided, evenly dispersed particulates is a white pigmenting agent imparting a milky-white appearance to the plastic film.

22. The combination of claim 16, said film being flexible.

23. The combination of claim 15, said rear surface of said metallized coating being unbacked.

24. The combination of claim 15, in combination with a photographic projection source directing light rays to said front surface.

25. The combination of claim 20, and a supporting frame for said screen having a front side and a rear side and means to mount said screen on said frame with the front surface of said film facing in the same direction as the front side of said frame, and with said screen having a flat soft panel.