Phottopatterning of liquid crystals (LCs) is a method used to align LCs with light-sensitive materials. A photosensitive layer is applied to the surface and selectively exposed to polarized light through a mask or by direct writing. Light exposure orders molecules in the layer, leading to LC molecules ordering in contact with this layer. This tehnique is key in optolectronic devices, because it enables accurate control over molecules orientation and optical properties.
As part of my master's thesis, I upgraded an already existing system for photopatterning with a laser light that enabled photopatterning with a standard video projector light. First, I present the theoretical background, the optical system for photopatterning and the preparation of LC cells. I prepared different types of LC cells with diverse structures, with which I investigated the optimal parameters for both modes of photopattering and characterized the quality of the resulting LC structures. Finally, I comment on how photopatterning with laser light performs compared to projector light and suggest possible improvements.
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