Liquid Crystals for Adaptive Optics

Adaptive optics components have been used for almost twenty years without major modifications of the basic hardware. Problems connected with cost, power consumption and reliability have pushed several groups to start, investigating the possibility of using different technologies. Of the many technologies under investigation two, in our opinion, demonstrate a high possibility of being an alternative to conventional adaptive mirrors. They are liquid crystal spatial light modulators and and micro-machined mirrors. The USAF Phillips Laboratory, is investigating both these technologies, however here we report, on the results of the liquid crystal work, which has a slightly longer history and more maturity.