Polarizing beam splitter assembly having reduced stress

• US 20060221445A1
• Filed: 03/31/2005
• Published: 10/05/2006
• Est. Priority Date: 03/31/2005
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: DiZio, James P., Nelson, Maureen C., Mazurek, Mieczyslaw H., Winkler, Wendi J., Ma, Jiaying, Sherman, Audrey A., Case, Marvin Jeffrey
• Granted Patent: US 7,315,418 B2
• Time in Patent Office: Days
• US Class Current: 359/487
• CPC Class Codes: G02B 27/283 used for beam splitting or combining
• CPC Class Codes: G02B 5/3041 comprising multiple thin layers, e.g. multilayer stacks
• CPC Class Codes: H04N 9/315 Modulator illumination systems general applications of lighting devices F21V; general optical systems G02B; lamp houses for projectors not peculiar to the presence of an electronic spatial light modulator G03B21/20

Abstract

A polarizing beam splitter includes a multilayer polarizing film, a first cross-linked silicone gel layer disposed on the multilayer polarizing film, a first rigid cover disposed on the cross-linked silicone gel layer, and a second rigid cover disposed adjacent to the multilayer polarizing film.

Claims

1. A polarizing beam splitter, comprising:

a multilayer polarizing film;

a first cross-linked silicone gel layer disposed on the multilayer polarizing film;

a first rigid cover disposed on the cross-linked silicone gel layer; and

a second rigid cover disposed adjacent to the multilayer polarizing film.

2. A polarizing beam splitter according to claim 1, further comprising a second cross-linked silicone gel layer disposed between the second rigid cover and the multilayer polarizing film.

3. A polarizing beam splitter according to claim 1, wherein the first cover is a prism and the second cover is a prism.

4. A polarizing beam splitter according to claim 1, wherein the first cover is a glass prism and the second cover is a glass prism.

5. A polarizing beam splitter according to claim 1, wherein the multilayer polarizing film is a multilayer polyester polarizing film.

6. A polarizing beam splitter according to claim 1, wherein the multilayer polarizing film is a multilayer reflective polarizing film.

7. A polarizing beam splitter according to claim 1, wherein the multilayer polarizing film is a matched z-index multilayer reflective polarizing film.

8. A polarizing beam splitter according to claim 1, wherein the first cross-linked silicone gel layer comprises a cross-linked silicone gel layer having a refractive index in a range from 1.50 to 1.58.

9. A polarizing beam splitter according to claim 1, wherein the first cross-linked silicone gel layer comprises cross-linked phenylmethylsilicone.

10. A polarizing beam splitter according to claim 9, wherein the first cross-linked silicone gel layer comprises cross-linked phenylmethylsilicone and phenylmethylsilicone oil.

11. A polarizing beam splitter according to claim 2, wherein the second cross-linked silicone gel layer comprises cross-linked phenylmethylsilicone.

12. A polarizing beam splitter according to claim 11, wherein the second cross-linked silicone gel layer comprises cross-linked phenylmethylsilicone and phenylmethylsilicone oil.

13. A polarizing beam splitter according to claim 1, wherein the first cross-linked silicone gel layer has a thickness in a range from 0.5 to 150 micrometers.

14. A polarizing beam splitter according to claim 1, wherein the second cross-linked silicone gel layer has a thickness in a range from 0.5 to 150 micrometers.

15. A projection system, comprising:

a light source to generate light;

an imaging core to impose an image on generated light from the light source to form image light, wherein the imaging core comprises at least one polarizing beam splitter and at least one imager, wherein the polarizing beam splitter comprises;

a multilayer reflective polarizing film;

a first cross-linked silicone gel layer disposed on the multilayer reflective polarizing film and between the light source and the multilayer reflective polarizing film;

a first rigid cover disposed on the first cross-linked silicone gel layer;

a second rigid cover disposed adjacent to the multilayer reflective polarizing film; and

a projection lens system to project the image light from the imaging core.

16. A projection system according to claim 15, further comprising a second cross-linked silicone gel layer disposed between the second rigid cover and the multilayer polarizing film.

17. A projection system according to claim 15, wherein the multilayer reflective polarizing film comprises a matched z-index multilayer reflective polarizing film.

18. A projection system according to claim 15, wherein the first cross-linked silicone gel layer comprises cross-linked phenylmethylsilicone.

19. A method of making a polarizing beam splitter, the method comprising:

disposing a multilayer reflective polarizing film between a first rigid cover and a second rigid cover, wherein a first cross-linked silicone gel layer is between the multilayer reflective polarizing film and the first cover and a second cross-linked silicone gel layer is between the multilayer reflective polarizing film and the second cover.

20. A method according to claim 19, further comprising curing a first silicone material to form a first cross-linked silicone gel layer prior to the disposing a multilayer reflective polarizing film between a first rigid cover and a second rigid cover step.

21. A method according to claim 19, further comprising curing a first silicone material to form a first cross-linked silicone gel layer, after the disposing a multilayer reflective polarizing film between a first rigid cover and a second rigid cover step.

22. A method according to claim 19, further comprising curing a first silicone material to form a first cross-linked silicone gel layer and curing a second silicone material to form a second cross-linked silicone gel layer, prior to the disposing a multilayer reflective polarizing film between a first rigid cover and a second rigid cover step.

23. A method according to claim 19, further comprising curing a first silicone material to form a first cross-linked silicone gel layer and curing a second silicone material to form a second cross-linked silicone gel layer, after the disposing a multilayer reflective polarizing film between a first rigid cover and a second rigid cover step.

24. A method according to claim 19, further comprising combining a silicone oil with a cross-linked silicone gel to form a first cross-linked silicone gel layer.

25. A method according to claim 19, further comprising combining a silicone oil with a cross-linked silicone gel to form the first cross-linked silicone gel layer and the second cross-linked silicone gel layer.