RAPID OPTICAL FABRICATION WITH COMPUTER CONTROLLED OPTICAL SURFACING

Abstract

The design needs for large optical components for advanced strategic defense systems and reconnaissance systems presented the optical industry with fabrication capability requirements that could not be met by conventional fabrication methods rooted in telescope making techniques . Conventionally , large telescope minors were made of solid round blanks that were ground with loose abrasive and subsequently polished to final shape on large lapping' The main features of large minor components in current advanced space-borne systems are the lightweight requirement and size restriction for individual components dictated by volumetric capacity of the deployment vehicles. They can be categorized into three groups: thin onor off-axis facesheets for active systems (Fig. 1), thin lightweight onor off-axis panels for active or semiactive systems (Fig. 2), and lightweight thick mirror structures predominantly on-axis for passive systems (Fig. 3). They all have one common feature that makes them unsuitable for conventional optical fabrication. They all will deform under the pressure of conventional lapping tools. In the case of light-