<title>The Testing Of Large Telescope Systems Using Multiple Subapertures</title>

Abstract

This paper describes an experiment, currently in progress at the Air Force Weapons Laboratory, on the testing of telescope systems using multiple subapertures for the auto-collimating optics. This method of optical testing is being considered as a cost-effective means for testing large aperture telescope systems of the future. While much progress has been made in finding analytical techniques for reconstructing the full-aperture wavefront from the subaperture data, no experiment has been performed to verify these analytical techniques. Several theoretical aspects of subaperture testing are described with the help of the Thunen-Kwon analytical technique and a covariance matrix calculation. Among these aspects are the contribution of each full-aperture Zernike polynomial to subaperture tilt, and the difficulty in detecting certain Zernike aberrations due to the symmetry of the subaperture configuration. No experimental results were available at the time of this writing, but the experiment plan is described. The aim of the experiment is to show that aberrations introduced into a wavefront by an optical system may be correctly retrieved using subaperture testing.