Optical compensation film for liquid crystal display

• US 6,822,713 B1
• Filed: 11/27/2000
• Issued: 11/23/2004
• Est. Priority Date: 11/27/2000
• Status: Expired due to Fees

• Current Assignee: Kent State University
• Original Assignee: Kent State University
• Inventors: Chien, Liang-Chy, Sergan, Tatiana, Yaroshchuk, Oleg, Reznikov, Yuriy, Kelly, Jack R.
• Primary Examiner(s): Dudek, James A.
• Application Number:
  US09/722,991
• Time in Patent Office: 1,457 Days
• Field of Search: 349/117, 349/118, 349/119
• US Class Current: 349/117
• 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 1/13363 Birefringent elements, e.g. for optical compensation
• CPC Class Codes: G02F 1/133634 the refractive index Nz perpendicular to the element surface being different from in-plane refractive indices Nx and Ny, e.g. biaxial or with normal optical axis

Abstract

An optical compensation film for a liquid crystal display is provided wherein the film is a polymer that is capable of producing light induced anisotropy. The film is irradiated with light to form an optical axis or axes.

Claims

1. An optical compensation film for a liquid crystal display comprising a polymer capable of producing light induced anisotropy characterized in that the polymer has a controlled in-plane and out-of-plane optical retardation, wherein the polymer is selected from the group consisting of polymers represented by the formulae:

and mixtures thereof, wherein x is a number between about 4 and about 16, and wherein each n is independently a number from about 10 to about 1000.

2. The optical compensation film of claim 1, wherein the polymer has been irradiated with light that is at least one of linearly polarized light, elliptically polarized light, circularly polarized light, partially polarized light, and non-polarized light.

3. The optical compensation film of claim 1, wherein the polymer has been irradiated a plurality of times a wherein the light on subsequent irradiations has at least one of a different polarization and a different angle with respect to a plane formed by the film.

4. The optical compensation film of claim 1, wherein the film is a plane and has a biaxial structure, and the film has optical axes that are each one of oriented to the plane in one of lying in the plane of the film, perpendicular to the plane of the film, tilted to the plane of the film, and changing across the film, and wherein the optical axes are oriented different from each other.

5. A liquid crystal display comprising two opposed substrates, electrodes disposed on facing sides of the two opposed substrates, the optical compensation film of claim 1 disposed on at least one of the electrodes, and a liquid crystal disposed between the substrates.

6. The optical compensation film of claim 1, wherein the compensation film is selected from the group consisting of a negative A film, a positive A film, a positive C film and a positive O film.

7. An optical compensation film for a liquid crystal display comprising a polymer capable of producing light induced anisotropy characterized in that the polymer has a controlled in-plane and out-of-plane optical retardation, wherein the polymer is selected from the group consisting of polymers represented by the formulae:

wherein n is a number from about 10 to about 1000.

8. The optical compensation film of claim 7, wherein the polymer has been irradiated with light that is at least one of linearly polarized list, elliptically polarized light, circularly polarized light, partially polarized light, and non-polarized light.

9. The optical compensation film of claim 7, wherein the polymer has been irradiated a plurality of times and wherein the light on subsequent irradiations has at least one of a different polarization and a different angle with respect to a plane formed by the film.

10. The optical compensation film of claim 7, wherein the film is a plane and has a biaxial structure, and the film has optical axes that are each one of oriented to the plane in one of lying in the plane of the film, perpendicular to the plane of the film, tilted to the plane of the film, and changing across the film, and wherein the optical axes are oriented different from each other.

11. A liquid optical display comprising two opposed substrates, electrodes disposed on facing sides of the two opposed substrates, the optical compensation film of claim 7 disposed on at least one of the electrodes, and a liquid crystal disposed between the substrates.