Diamond Turning Wavefront Correctors: Opening New Optical Design Flexibilities

Abstract

A wavefront corrector (WFC) is a component in an optical system Which corrects for errors of an earlier optic which is imaged onto it. WFC's can be used in two-stage optics in which a primary mirror with large surface errors can be incorporated in the "fovea] mode" to make an ultra-wide-field system and yield an upgraded high acuity image. WFC's, therefore, offer significant cost advantage for fabricating large telescope primaries. We report the JPL-LLNL first embodiment of this concept which includes a non-axisymmetric WFC containing greater than a wave of astigmatism and two waves of coma (1 wave = 0.63 μm). The 6 cm diameter WFC was diamond turned on a super invar substrate covered with 13% phosphorous electroless nickel. Metrology of the WFC with this great an error to 10th wave accuracy was challenging.© (1987) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.