Manufacturing and evaluation of membrane optical elements for ultra-lightweight optics

SRS Technologies has made significant strides in the research and development of ultra-lightweight membrane optics for future imaging applications while conducting work with NASA Marshall Space Flight Center and the Air Force Research Lab. Thin film mirrors have been manufactured using surface replication casting of CP1(TM), a polyimide material developed specifically for space applications. In the course of such efforts processing and manufacturing techniques have been developed to produce polyimide membranes with surface roughness below 1.5 nanometers rms and sub-wavelength thickness variation for both curved and flat membranes. This has led to the production of membranes optically flat to lambda/13 (lambda=633nm) and curved membranes with figure error on the order of microns over half-meter diameters. This accuracy places such membranes within the demonstrated correctable range of several advanced wavefront correction technologies.