Laser interferometry measurement using the volatility of light, with the advantages on high resolution, high accuracy, high sensitivity and reproducibility, it has become the primary means of the optical shape measurement. Laser wavelength scanning interference moves the test aspheric mirror in the optical axis direction controlled by the electric translation stage precisely, gradually changes the relative distance between the aspheric test mirror and the interferometer. Thus the reference sphere wavefronts with different radius match automatically to different ring-zones of the aspheric mirror. Based on the laser wavelength scanning interference testing of aspheric surface, this paper calculates the center area and the annular area separately. In the annular area processing, the authors use Zernike polynomials to fit the phase diagram, then derivative along the radial direction, to extract the zero-phase points on the interferogram of each relative position, and get the angle between the normal and the aspheric axis, then rebuild the absolute position of the coordinate system of aspheric mirror. Experimental results show that the method has high accuracy and reliability.

Date Published: 16 October 2012
PDF: 6 pages
Proc. SPIE 8416, 6th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, 841625 (16 October 2012); doi: 10.1117/12.2009280

Published in SPIE Proceedings Vol. 8416:
6th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies
Li Yang; Eric Ruch; Shengyi Li, Editor(s)