 During 1992, Rockwell applied micro-optics to the system development of several industrial applications, including, microlenses for silicon focal planes, high speed binary microlens in GaAs, antireflection surfaces in silicon, thin film microlens arrays, beam steering device, microlens integration with focal plane arrays, and optical transformer and collimator.Rockwell Science Center also developed refractive microlens technology, including gray scale photolithography.Diffractive microlenses based on binary optic structures are typically fabricated in bulk material by multiple sequential layers of photoresist patterning and reactive ion etching (RIE), to form a multi-step phase profile.