Computer generated holograms (CGHs) are widely used in aspheric surface testing and metrology. The primary role of the CGHs is to generate any desired wavefronts to realize phase compensation. In order to eliminate alignment errors of CGH and the tested aspheric, this paper designs a new layout of CGH that has the advantages of high alignment accuracy and simple experimental operation. And further the influence of the location deviation of CGH and the tested aspheric mirror to the entire system is discussed; it shows that the error introduced by the CGH and the tested aspheric mirror tilting around the x-axis or y-axis as well as the tested aspheric mirror moving along the x-axis or y-axis direction is large. Then the CGH design principle and design process are reviewed. Finally, a CGH is designed for measurement of an aspheric mirror (diameter=226mm, F-number =2.2). Interferometric test results of an aspheric mirror show that the whole test system obtains the demanded high accuracy.

Date Published: 13 May 2013
PDF: 10 pages
Proc. SPIE 8788, Optical Measurement Systems for Industrial Inspection VIII, 87882O (13 May 2013); doi: 10.1117/12.2019864

Published in SPIE Proceedings Vol. 8788:
Optical Measurement Systems for Industrial Inspection VIII
Peter H. Lehmann; Wolfgang Osten; Armando Albertazzi, Editor(s)