화학공학소재연구정보센터
Molecular Crystals and Liquid Crystals, Vol.424, 75-75, 2004
Liquid crystal alignment by holographic surface relief grating inscribed on azo-polymer film
We found that the surface relief grating direction (SRG) made the nematic liquid crystal (LC) align along the grating direction. The SRGs were photo-fabricated on a liquid crystalline azobenzene side-chain, polymer film by the conventional holographic method, The twisted nematic liquid crystal (TNLC) cell was prepared using two SRG substrates or two rubbed polyimide substrates as alignment layers, and the LC alignment was investigated by measuring the transmittance of a 90degrees-TNLC cell located between crossed polarizers. The LC aligning process was studied. in-situ using the hybrid LC cell with the rubbed polyimide substrate and the SRG substrate as the reference and the test alignment layers, respectively. The in-situ transmission data show that the topological effect by the SRG formation and the intermolecular interaction effect by the azo chromophore alignment compete with each other.