The aspheric mirror can correct aberrations and improve imaging quality of optical system . M oreover using such mirror can reduce the num ber of optical elem ents in an optical system and further reduce the weight and size of the system . In order to improve the accuracy of aspheric mirror fabrication, there are many methods used to m easure aspheric mirror. Am ong these methods, the most popular one is interferom etry which can m easure the surface with very high accuracy. However, interferom etry commonly requires com plicated and expensive assistant optics, and its m easurem ent range is limited. In order to measure aspheric mirror conveniently and effectively, we further evolve the well know n approaches of 'Phase M easuring Deflectom ety'(PM D) to measure such surface. In this study, we present a novel m ethod based on fringe reflection to m easure aspheric m irror. In the m easurem ent process, the screen and the cam era are m oved along the mirror optical axis, respectively. Using the phase information of the recording fringe patterns, for each cam era pixel, we can calculate the slope and coordinate of its corresponding point on the surface to be tested. By integrating, the absolute height of the tested surface can be reconstructed. Com pared with traditional PM D, this m ethod can m easure the absolute height of an aspheric m irror unam biguously and doesn't need com plex calibration.

Date Published: 20 May 2009
PDF: 4 pages
Proc. SPIE 7283, 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, 72831B (20 May 2009); doi: 10.1117/12.828659

Published in SPIE Proceedings Vol. 7283:
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment
Yudong Zhang; James C. Wyant; Robert A. Smythe; Hexin Wang, Editor(s)