Three-Position Absolute Measurement Simulation And Error Analysis

To meeting the testing requirements of high-precision optical surfaces, the absolute testing technology was used for the optical testing process. Three-Position absolute measurements with the advantage of few requested testing and testing conditions are often easily satisfaction were used to high-precision spherical surface shape testing. However in the error process of three-position absolute measurements, cat's position error has an important impact on finally measurement results, so three-position absolute measurement simulation and error analysis is necessary. In this paper, optical design software ZEMAX were used to built the model of three-position absolute measurement and three-position absolute sphere testing algorithm was used to get actual surface. Finally, some experiments about how to determine the location of standard cat's eye position were carried on and the experiment's result shows that defocus is the most important factor in cat's eye position measurement.