ABSTRACT
This chapter highlights many of the advances made in the use of liquid crystals (LC) for laser applications from 1982 through 1992. It discusses new materials, specifically ferroelectric LCs and LC polymers. The chapter reviews new developments in passive applications for cholesterics and nematics. Special molecular ordering, which creates optical properties such as selective reflection in the LC phase, may be frozen into the bulk polymer by high viscosity near the glass transition. Because of the flexible spacer between the pendant LC moiety and the polymer main chain, LC polymers can respond to external fields. Electric field threshold voltages are comparable to those of conventional LCs, provided the pendant spacer length is short. The optical field reflected by a chiral-nematic LC preserves its sense of polarization, whereas the field reflected by a dielectric mirror changes its polarization from right to left circular or vice versa.
