Optical component

• US 5,602,661 A
• Filed: 02/10/1994
• Issued: 02/11/1997
• Est. Priority Date: 02/17/1993
• Status: Expired due to Term

• Current Assignee: Rolic AG (BASF SE)
• Original Assignee: Hoffmann-La Roche Incorporated (Roche Holding AG)
• Inventors: Schmitt, Klaus, Schadt, Martin
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Parker, Kenneth
• Application Number:
  US08/194,234
• Time in Patent Office: 1,097 Days
• Field of Search: 359/75, 359/76, 359/73, 359/99, 359/103, 359/105, 522/2, 522/150, 428/1, 430/270, 430/290
• US Class Current: 349/124
• CPC Class Codes: C08F 246/00 Copolymers in which the nature of only the monomers in minority is defined
• CPC Class Codes: C08G 77/38 Polysiloxanes modified by chemical after-treatment C08G77/045 takes precedence
• CPC Class Codes: G02F 1/133711 by organic films, e.g. polymeric films
• CPC Class Codes: G02F 1/133753 with different alignment orientations or pretilt angles on a same surface, e.g. for grey scale or improved viewing angle
• CPC Class Codes: G02F 1/133765 without a surface treatment
• CPC Class Codes: G02F 1/133788 by light irradiation, e.g. linearly polarised light photo-polymerisation

Abstract

An optical component includes an anisotropic layer of cross-linked liquid crystal monomers with varying local orientation of the liquid crystal molecules. The liquid crystal layer is in contact with an orientation layer comprising a photo-orientable polymer network (PPN). A method of making includes orienting the liquid crystal monomers by the interaction with the PPN layer and subsequently fixing the molecules by cross-linking.

Claims

1. An optical component comprising (a) an anisotropic film of cross-linked liquid crystal monomers with varying local orientation of the liquid crystal molecules and (b) an orientation layer comprising a photo-orientable polymer network (PPN), said orientation layer being in contact with said anisotropic liquid crystal film.

2. The optical component according to claim 1, wherein the orientation layer has an orientation of the polymer molecules which differs in locally limited regions.

3. The optical component according to claim 2, wherein the direction of the optical axis of the anisotropic film varies with the orientation of the polymer molecules in the orientation layer.

4. A method of producing an optical component comprising (a) an anisotropic film of cross-linked liquid crystal monomers with varying local orientation of the liquid crystal molecules and (b) an orientation layer comprising a photo-orientable polymer network (PPN), said orientation layer being in contact with said anisotropic liquid crystal film wherein the liquid crystal monomers are oriented by interaction with the PPN layer, said orientation fixed in a subsequent cross-linking step.

5. The method according to claim 4, wherein the cross-linking occurs by irradiation of said liquid crystal monomers with light.

6. The method according to claim 4, wherein the cross-linkable liquid crystal monomers are diacrylates and the materials in the orientation layer are cinnamate derivatives.

7. The method according to claim 4, wherein the cross-linking is carried out in a cell made up of two parallel, orientation layers.

8. The method according to claim 7, wherein one of the two orientation layers is removed after cross-linking.

9. The method according to claim 4, wherein a layer coated with PPN is selectively structured by repeated illumination with linear-polarized UV light having a varying direction of polarization, after which the cross-linkable liquid crystal material is oriented and cross-linked by spin-coating or immersion.

10. The method according to claim 4, wherein the cross-linkable liquid crystal material consists of mixtures of multi-functionalized liquid crystal monomers and functionalized dichroic chromophores.

11. The method according to claim 4, wherein the cross-linkable liquid crystal material consists of mixtures of multi-functionalized liquid crystal monomers and chiral molecules.

12. The method according to claim 4, wherein the cross-linkable liquid crystal material comprises mixtures of multi-functionalized liquid crystal monomers and functionalized liquid crystal monomers with an axial or lateral permanent dipole moment, such that these mixtures have positive or negative dielectric anisotropy.

13. The use of an optical component as a retarder layer, wherein said optical component comprises (a) an anisotropic film of cross-linked liquid crystal monomers with varying local orientation of the liquid crystal molecules and (b) an orientation layer comprising a photo-orientable polymer network (PPN), said orientation layer being in contact with said anisotropic liquid crystal film.

14. The use of an optical component as a cholesteric filter, wherein said optical component comprises (a) an anisotropic film of cross-linked liquid crystal monomers with varying local orientation of the liquid crystal molecules and (b) an orientation layer comprising a photo-orientable polymer network (PPN), said orientation layer being in contact with said anisotropic liquid crystal film.

15. The use of an optical component as a dichroic filter, wherein said optical component comprises (a) an anisotropic film of cross-linked liquid crystal monomers with varying local orientation of the liquid crystal molecules and (b) an orientation layer comprising a photo-orientable polymer network (PPN), said orientation layer being in contact with said anisotropic liquid crystal film.

16. The use of an optical component as a dichroic polarizer, wherein said optical component comprises (a) an anisotropic film of cross-linked liquid crystal monomers with varying local orientation of the liquid crystal molecules and (b) an orientation layer comprising a photo-orientable polymer network (PPN), said orientation layer being in contact with said anisotropic liquid crystal film.

17. The use of an optical component as a polarization rotator, wherein said optical component comprises (a) an anisotropic film of cross-linked liquid crystal monomers with varying local orientation of the liquid crystal molecules and (b) an orientation layer comprising a photo-orientable polymer network (PPN), said orientation layer being in contact with said anisotropic liquid crystal film.

18. The use of an optical component as an image-carrier cell in which the image information is stored by variously oriented cell segments, wherein said optical component comprises (a) an anisotropic film of cross-linked liquid crystal monomers with varying local orientation of the liquid crystal molecules and (b) an orientation layer comprising a photo-orientable polymer network (PPN), said orientation layer being in contact with said anisotropic liquid crystal film.

19. The use of an optical component in a three-dimensional projection system, wherein said optical component comprises (a) an anisotropic film of cross-linked liquid crystal monomers with varying local orientation of the liquid crystal molecules and (b) an orientation layer comprising a photo-orientable polymer network (PPN), said orientation layer being in contact with said anisotropic liquid crystal film.