Multilayer optical bodies

• US 6,888,677 B2
• Filed: 10/17/2003
• Issued: 05/03/2005
• Est. Priority Date: 12/21/1993
• Status: Expired due to Term

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Hebrink, Timothy J., Wheatley, John A., Ouderkirk, Andrew J., Condo, Peter D., Liu, Yaoqi J., Ruff, Andrew T., Andrus, Milton H. Jr.
• Primary Examiner(s): Epps, Georgia
• Assistant Examiner(s): Dinh, Jack
• Application Number:
  US10/688,468
• Publication Number:
  US 20040085642A1
• Time in Patent Office: 564 Days
• Field of Search: 359/265, 359/359, 359/580, 359/582, 359/584, 359586-589, 359/592, 359/593, 359/498, 345/49, 345/105, 428/212
• US Class Current: 359/360
• CPC Class Codes: B29C 55/023 using multilayered plates or sheets
• CPC Class Codes: B29D 11/00 Producing optical elements, e.g. lenses or prisms grinding or polishing of optical elements B24B; constructional form of optical elements G02B; optical parts of spectacles G02C7/00
• CPC Class Codes: B29K 2995/003 Reflective
• CPC Class Codes: B29K 2995/0034 Polarising
• CPC Class Codes: B32B 2307/416 Reflective
• CPC Class Codes: B32B 2307/42 Polarizing, birefringent, filtering
• CPC Class Codes: B32B 2551/00 Optical elements
• CPC Class Codes: B32B 2551/08 Mirrors
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/36 comprising polyesters
• CPC Class Codes: B32B 7/023 Optical properties
• CPC Class Codes: G02B 27/283 used for beam splitting or combining
• CPC Class Codes: G02B 5/0841 comprising organic materials, e.g. polymers
• CPC Class Codes: G02B 5/26 Reflecting filters G02B5/28 takes precedence
• CPC Class Codes: G02B 5/287 comprising at least one layer of organic material
• CPC Class Codes: G02B 5/3025 Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state G02B5/3008, G02B5/3016 take precedence
• CPC Class Codes: G02B 5/3041 comprising multiple thin layers, e.g. multilayer stacks
• CPC Class Codes: G02B 5/305 including organic materials, e.g. polymeric layers
• CPC Class Codes: G02B 5/3083 Birefringent or phase retarding elements G02B5/3008, G02B5/3016 take precedence; systems for polarisation control G02B27/286; manufacturing phase modulating patterns by lithographic processes G03F7/001
• CPC Class Codes: G02F 1/133536 Reflective polarizers G02F1/13362 takes precedence
• CPC Class Codes: G02F 1/133545 : Dielectric stack polarisers
• CPC Class Codes: G02F 1/13362 : providing polarized light, e.g. by converting a polarisation component into another one
• CPC Class Codes: Y10S 428/91 : Product with molecular orientation
• CPC Class Codes: Y10T 428/24942 : including components having same physical characteristic in differing degree
• CPC Class Codes: Y10T 428/3154 : Of fluorinated addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31786 : Of polyester [e.g., alkyd, etc.]
• CPC Class Codes: Y10T 428/31797 : Next to addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31935 : Ester, halide or nitrile of addition polymer

Abstract

Optical bodies, comprising: a plurality of first optical layers comprising a first polymer composition that comprises (i) a polyester portion having terephthalate comonomer units and ethylene glycol comonomer units, and (ii) a second portion corresponding to a polymer having a glass transition temperature of at least about 130° C.; and a plurality of second optical layers disposed in a repeating sequence with the plurality of first optical layers. Also disclosed are optical bodies comprising: (a) a plurality of first optical layers, each first optical layer being oriented; and (b) a plurality of second optical layers, disposed in a repeating sequence with the plurality of first optical layers, comprising a blend of polymethylmethacrylate and polyvinylidene fluoride. Methods of making the above-described optical bodies, and articles employing such optical bodies are also provided.

Claims

1. An optical body, comprising:

a plurality of first optical layers, each first optical layer being oriented and comprising a polyester having terephthalate comonomer units and ethylene glycol comonomer units; and

a plurality of second optical layers disposed in a repeating sequence with the plurality of first optical layers, each second optical layer comprising a copolymer of polymethyl methacrylate that contains comonomer units that depress a glass transition temperature of the copolymer below a glass transition temperature of the polyester of the first optical layers;

the optical body being configured and arranged to reflect at least a portion of light over at least one wavelength region.

2. The optical body of claim 1, wherein the comonomer units are selected from ethyl acrylate, butyl acrylate, n-butyl methacrylate, and ethyl methacrylate.

3. The optical body of claim 1, wherein the first optical layers have an in-plane birefringence of at least about 0.05.

4. The optical body of claim 1, wherein at least one in-plane index of refraction of the first optical layers differs by at least about 0.1 from an in-plane index of refraction, in the same direction, of the second optical layers.

5. The optical body of claim 1, wherein the optical body is configured and arranged to reflect at least a substantial portion of light in a visible wavelength region.

6. The optical body of claim 5, wherein the optical body has a blue appearance that shifts to red as the viewing angle increases with respect to normal incidence.

7. The optical body of claim 1, wherein the optical body is configured and arranged to reflect a substantial portion of light in an infrared wavelength region.

8. The optical body of claim 1, wherein the first polyester is polyethylene terephthalate.

9. The optical body of claim 1, wherein the first and second optical layers are coextruded.

10. The optical body of claim 1, wherein the first optical layers are biaxially oriented.

11. The optical body of claim 1, wherein z-axis refractive indices of the first and second optical layers differ by no more than about 0.04.

12. An article, comprising:

a mirror comprising

a plurality of first optical layers, each first optical layer being oriented and comprising a polyester having terephthalate comonomer units and ethylene glycol comonomer units, and

a plurality of second optical layers disposed in a repeating sequence with the plurality of first optical layers, each second optical layer comprising a copolymer of polymethyl methacrylate that contains comonomer units that depress a glass transition temperature of the copolymer below a glass transition temperature of the polyester of the first optical layers,

the mirror being configured and arranged to reflect at least a portion of light over at least one wavelength region.

13. The article of claim 12, wherein the mirror is configured and arranged to reflect a substantial portion of light in an infrared wavelength region.

14. The article of claim 12, wherein the mirror is configured and arranged to reflect a substantial portion of light in a visible wavelength region.

15. The article of claim 12, wherein the mirror is configured and arranged to reflect a substantial portion of light in an ultraviolet wavelength region.

16. An article, comprising:

a light source; and

an optical body disposed to receive light from the light source, the optical body comprising

a plurality of first optical layers, each first optical layer being oriented and comprising a polyester having terephthalate comonomer units and ethylene glycol comonomer units, and

a plurality of second optical layers disposed in a repeating sequence with the plurality of first optical layers, each second optical layer comprising a copolymer of polymethyl methacrylate that contains comonomer units that depress a glass transition temperature of the copolymer below a glass transition temperature of the polyester of the first optical layers,

the optical body being configured and arranged to reflect at least a portion of light over at least one wavelength region.

17. The article of claim 16, wherein the optical body is configured and arranged to reflect a substantial portion of light in an infrared wavelength region.

18. The article of claim 16, wherein the optical body is configured and arranged to reflect a substantial portion of light in a visible wavelength region.

19. The article of claim 16, wherein the optical body is configured and arranged to reflect a substantial portion of light in an ultraviolet wavelength region.

20. The article of claim 16, wherein z-axis refractive indices of the first and second optical layers differ by no more than about 0.04.