Photo-sculpting technology for the fabrication of complex surfaces for micro-optic and micro-engineering applications

摘要

Summary form only given. The authors describe a generic technology which can enable the fabrication of surface relief structures of great complexity. The initial work was aimed at providing micro-optic lens plates for improving the performance of infrared detectors. For improved optical efficiency, the need arose for high fill factor lens with aspheric surfaces and eventually for combined refractive-diffractive lens. It was necessary then to develop a completely new process. The new process was based on the observation that positive photoresist exposes progressively through the thickness of the film on increasing illumination with UV. The authors' work has been directed at developing an exposure technique which allows a carefully controlled exposure dose at each point in the film. In this way the pattern of light intensities is transformed into vertical relief in the photoresist.