Micro-mechanical laser mirror - has multilayer dielectric or metallic coating on silicon@ substrate which is completely etched away in optically-active region to provide floating mirror actuated capacitively, magnetically or piezoelectrically.

摘要

A highly polished substrate of Si with (110) or (100) crystal orientation is coated over an area in the path of the laser beam with a multilayer sandwich of silica and silicon nitride e.g. by chemical vapour deposition. The substrate is etched so that the active area is supported by two oppositely directed cantilevers, one of which carries an electrode contact. Alternatively the movements of the mirror may be controlled by piezoelectrically or magnetically. ADVANTAGE - No substrate materials other than semiconducting Si are used, and mirror can execute very rapid movements at high frequency in adaptive optical system.