Polarizing beam splitter plates providing high resolution images and systems utilizing such polarizing beam splitter plates

• US 9,851,576 B2
• Filed: 08/09/2013
• Issued: 12/26/2017
• Est. Priority Date: 08/15/2012
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Ouderkirk, Andrew J., Carls, Joseph C.
• Primary Examiner(s): Dowling, William C
• Application Number:
  US14/406,570
• Publication Number:
  US 20150177531A1
• Time in Patent Office: 1,600 Days
• CPC Class Codes: B32B 2037/109 using a squeegee
• CPC Class Codes: B32B 2551/00 Optical elements
• CPC Class Codes: B32B 37/0038 involving application of liquid to the layers prior to lamination, e.g. wet laminating B32B37/12 takes precedence
• CPC Class Codes: B32B 37/1018 using only vacuum
• CPC Class Codes: B32B 37/1027 Pressing using at least one press band
• CPC Class Codes: B32B 37/1284 Application of adhesive
• CPC Class Codes: B32B 37/18 involving the assembly of discrete sheets or panels only
• CPC Class Codes: B32B 38/10 Removing layers, or parts of layers, mechanically or chemically
• 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: G03B 21/2073 Polarisers in the lamp house peculiar to electronic spatial light modulators H04N9/3197

Abstract

Polarizing beam splitter plates and systems incorporating such beam splitter plates are described. The polarizing beam splitter plate includes a first substrate and a multilayer optical film reflective polarizer that is disposed on the first substrate. The polarizing beam splitter plate includes a first outermost major surface and an opposing second outermost major surface that makes an angle of less than about 20 degrees with the first outermost major surface. The polarizing beam splitter plate is adapted to reflect an imaged light received from an imager towards a viewer or screen with the reflected imaged light having an effective pixel resolution of less than 12 microns.

Claims

1. A polarization subsystem comprising:

a first imager; and

a polarizing beam splitter plate for receiving imaged light from the imager and comprising;

a first substrate;

a multilayer optical film reflective polarizer disposed on the first substrate;

a first outermost major surface; and

an opposing second outermost major surface making an angle of less than about 20 degrees with the first outermost major surface,

wherein the polarizing beam splitter plate reflects the received imaged light towards a viewer or screen with the reflected imaged light having an effective pixel resolution of less than 12 microns.

2. The polarization subsystem of claim 1, wherein the second outermost major surface makes an angle of less than about 5 degrees with the first outermost major surface.

3. The polarization subsystem of claim 1, wherein a maximum separation between the first and second outermost major surfaces is less than about 1 mm.

4. The polarization subsystem of claim 1, wherein at least one of the first and second outermost major surfaces comprises a curved portion.

5. The polarization subsystem of claim 1 further comprising a second substrate, the multilayer optical film reflective polarizer being disposed between the first and second substrates.

6. The polarization subsystem of claim 1, further comprising a projection lens that receives light from the polarizing beam splitter plate after light is imaged and projects it towards the viewer or screen.

7. The polarization subsystem of claim 1, wherein the multilayer optical film reflective polarizer has a surface roughness Ra of less than 45 nm or a surface roughness Rq of less than 80 nm.

8. A polarizing beam splitter plate comprising:

a first substrate;

a second substrate;

a multilayer optical film reflective polarizer disposed between and adhered to the first and second substrates;

a first outermost major surface; and

an opposing second outermost major surface making an angle of less than about 20 degrees with the first outermost major surface, wherein the polarizing beam splitter plate is adapted to reflect imaged light towards a viewer or screen, the reflected imaged light having an effective pixel resolution of less than 12 microns.

9. The polarizing beam splitter plate of claim 8, wherein the multilayer optical film reflective polarizer has a surface roughness Ra of less than 45 nm or a surface roughness Rq of less than 80 nm.

10. The polarizing beam splitter plate of claim 8, wherein at least one of the first and second substrates has a diffuse transmission of less than about 2%.

11. A projection subsystem, comprising:

a light source;

a first imager imaging light received from the light source; and

a polarizing beam splitter plate receiving the imaged light from the first imager and comprising;

a multilayer optical film reflective polarizer;

a first outermost major surface; and

an opposing second outermost major surface making an angle of less than about 20 degrees with the first outermost major surface;

wherein the polarizing beam splitter plate reflects the received imaged light towards an image plane with an effective pixel resolution of less than 12 microns.

12. A projection system comprising the projection subsystem of claim 11, the first imager being pixelated and comprising a plurality of pixels, the projection system projecting images of the pixels in the plurality of pixels onto a screen, each pixel having an expected location and area on the screen, an actual location of each pixel on the screen being within a circle centered on the expected location of the pixel and having an area that is less than 5 times the expected area of the pixel.

13. A projection system comprising the projection subsystem of claim 11, the first imager being pixelated and comprising a plurality of pixels, the projection system projecting images of the pixels in the plurality of pixels onto a screen, each pixel having an expected area on the screen and an actual area on the screen, the actual area of each projected pixel on the screen being less than 5 times the expected area of the projected pixel on the screen.

14. A polarization subsystem comprising:

a first imager; and

a polarizing beam splitter plate receiving imaged light from the imager and comprising;

a multilayer optical film reflective polarizer;

a first outermost major surface; and

an opposing second outermost major surface making an angle of less than about 20 degrees with the first outermost major surface;

wherein the polarizing beam splitter plate reflects the received imaged light towards a viewer or screen, and wherein the multilayer optical film reflective polarizer has a surface roughness Ra of less than 45 nm or a surface roughness Rq of less than 80 nm.

15. The projection subsystem of claim 14, wherein the multilayer optical film reflective polarizer has a surface roughness Ra of less than 40 nm or a surface roughness Rq of less than 70 nm.

16. A method of producing a flat film, comprising:

providing a multilayer optical film;

providing a temporary flat substrate;

releasably attaching a first surface of the multilayer optical film to the temporary flat substrate;

providing a permanent substrate, the permanent substrate comprising a first outermost major surface and an opposing second outermost major surface making an angle of less than about 20 degrees with the first outermost major surface;

attaching a second surface of the multilayer optical film to the permanent substrate; and

removing the multilayer optical film from the temporary flat substrate.

17. The method of claim 16, wherein the step of releasably attaching the first surface of the multilayer optical film to the temporary flat substrate comprises:

wetting the surface of the temporary flat substrate with a wetting agent to create a wet surface of the temporary flat substrate;

applying the multilayer optical film on the surface of the temporary flat substrate;

squeegeeing the multilayer optical film on the surface of the temporary flat substrate; and

allowing the multilayer optical film, the temporary flat substrate, and the wetting agent to dry.

18. The method of claim 17, wherein the step of allowing the multilayer optical film, the temporary flat substrate, and the wetting agent to dry causes the surface of the multilayer optical film to conform to the temporary flat substrate.

19. The method of claim 17, wherein the step of allowing the multilayer optical film, the temporary flat substrate, and the wetting agent to dry comprises wicking the wetting agent between the optical film and the flat substrate to edges of the multilayer optical film for the wetting agent to evaporate and causing a vacuum sealing between the multilayer optical film and the temporary flat substrate.

20. The method of claim 17, wherein a protective layer is applied to the multilayer optical film on the side opposite the surface applied to the flat substrate before squeegeeing.

21. A method of producing a polarizing beam splitter plate comprising:

applying an adhesive on the film produced by the method of claim 16 on the side of the film opposite the permanent substrate; and

applying a second permanent substrate against the adhesive.

22. The method of claim 16, wherein the surface of the multilayer optical film that previously faced the temporary flat substrate has a surface roughness of Ra of less than 45 nm or a surface roughness Rq of less than 80 nm.

23. A method of creating an optically flat polarizing beam splitter plate, comprising:

providing a multilayer optical film reflective polarizer;

applying a layer of pressure sensitive adhesive to a first surface of the multilayer optical film;

applying a first substrate against the pressure sensitive adhesive layer on the side opposite the multilayer optical film, the first substrate comprising a first outermost major surface and an opposing second outermost major surface making an angle of less than about 20 degrees with the first outermost major surface; and

applying vacuum to the pressure sensitive adhesive, the multilayer optical film, and the first substrate.

24. The method of claim 23 further comprising:

applying a second layer of adhesive to a second surface of the multilayer optical film opposite the first surface; and

applying a second substrate to the opposite side of the second layer of adhesive from the multilayer optical film, the second substrate comprising a first outermost major surface and an opposing second outermost major surface making an angle of less than about 20 degrees with the first outermost major surface.