Fast Response Liquid Crystals for Electro-Optic Applications

摘要

The objectives of this program are (1) to develop low voltage and highbirefringence LC mixtures, (2) to develop negative dielectric anistropic LC materials for high contrast display and wide-band infrared scene projectors, and (3) to deliver sample mixtures to device teams for testing. In the effort of developing high birefringence and low voltage LC mixtures for laser communications, we discovered some nitro-amino tolane dyes with very large dielectric anistropy and relatively low viscosity. Adding 10% of this guest to the nonpolar diphenyl-diacetylene host, the threshold votage drops from 4.0 to 1.5 V(rms). In the meantime, these new compounds possess a relatively low viscosity so that they do not increase the response time too noticeably. In the effort of developing negative dielectric an isotropy LC compounds, we have designed and synthesized (collaborated with Chiao Tun University) several laterally fluorinated tolanes and diacetylenes. These LC compounds exhibit a large but negative dielectric anisotropy. They are useful for high contrast displays and for wide-band infrared scene projectors. We have delivered sample mixtures to Raytheon Lexington Labs, Kent State University, and MacroVision Communication for testing their laser beam steering, low voltage display and fiber-optic communications devices, respectively.