초록 |
The polarizer is the essential optical element in LCDs. Conventional polarizers show limited thermal stability, low resistivity against solvents and large thickness. To overcome these limitations, thin film polarizers are in demand. One possible approach is based on the highly ordered guest-host system, in which the anisotropic absorption of light is achieved by aligning a dichroic dye (guest) in the cooperative motion of the LC (host) molecules. A new reactive LC monomer was designed and synthesized, which contains photo-polymerizable acrylate groups. To characterize the monomer, 1H-NMR, FT-IR, DSC and POM were used. The monomer exhibited highly ordered smectic phase at relatively low temperature. We fabricated thin film polarizer in a sandwich cell having rubbed alignment layers. High dichroic ratio (DR=20.7), order parameter (S=0.87) and polarization efficiency (PE>99%) were determined by polarized UV/Vis spectroscopy, which is much higher than the nematic thin film polarizers. |