Method for generating alignment on top of a liquid crystal polymer material
The present invention relates to a method for manufacturing an optical element including a layer comprising anisotropic optical function and alignment capability. The layer is formed from a composition comprising polymerizable liquid crystals and one or more photo-orientable substances. Alignment on top of the layer is achieved by exposure to linearly polarized light.
1. A layer structure comprising a layer made from polymerizable liquid crystal monomers and a photo-orientable substance;
wherein the layer has an upper surface and a middle of the layer,
wherein the layer has an optical anisotropic property and has alignment capability on the upper surface by providing an alignment direction,
wherein at least in one area of the upper surface the alignment direction provided by the layer is different from the liquid crystal orientation in the layer just beneath the upper surface.
2. The layer structure according to claim 1 , wherein the photo-orientable substance in the layer has a density gradient, such that the concentration of photo-orientable substance is higher at the upper surface of the layer than in the middle of the layer.
3. The layer structure according to claim 1 , wherein the photo-orientable substance comprises fluorinated and/or siloxane moieties and/or is a polysiloxane.
4. The layer structure according to claim 1 , wherein the layer further comprises isotropic or anisotropic fluorescent and/or non-fluorescent dyes, dichroic dyes and/or chiral additives.
5. The layer structure according to claim 1 , wherein the alignment direction provided by the polymerized liquid crystal of the layer is different at the upper surface of the layer than in the middle of the layer.
6. The layer structure according to claim 1 , which has an additional anisotropic layer in direct contact with the layer, the additional anisotropic layer comprising liquid crystal polymers, wherein the liquid crystal polymer of the additional anisotropic layer is aligned according to the alignment direction of the layer.
7. The layer structure according to claim 6 , wherein the layer and the additional anisotropic layer are configured such that the layer structure acts as an achromatic retarder.
8. An optical device comprising a reflective polarizer and an achromatic retarder comprising the layer structure as described in claim 7 .
9. A method of using a layer structure according to claim 1 , comprising providing the layer structure for antireflection for OLED displays.
10. The layer structure according to claim 1 , wherein the layer structure consists of a substrate and the layer made from polymerizable liquid crystal monomers and a photo-orientable substance on the substrate.
11. The layer structure according to claim 1 , wherein the layer structure consists of a substrate, an alignment layer on the substrate, and the layer made from polymerizable liquid crystal monomers and a photo-orientable substance on the alignment layer.
12. The layer structure according to claim 1 , wherein the layer structure consists of a primer coated substrate and the layer made from polymerizable liquid crystal monomers and a photo-orientable substance on the primer coated substrate.
13. The layer structure according to claim 1 , wherein the layer structure consists of a primer coated substrate, an alignment layer on the primer coated substrate, and the layer made from polymerizable liquid crystal monomers and a photo-orientable substance on the alignment layer.