A method using a wedge-plate shear shifting system with adjustable accuracy and measuring range is proposed for measuring the focus shifting caused by thermal distortion in a single-shot laser system. Two beam splitter groups are used in this method to precisely split a single beam into multiple beams with different optical path difference. The focus shifting is determined by position change of the minimum spot on the detector. This method is convenient and economic, especially as it powerfully solves the problem of catching focus shifting in an ultrashort time.
© 2013 Optical Society of America
Instrumentation, Measurement, and Metrology
Original Manuscript: December 6, 2012
Revised Manuscript: May 9, 2013
Manuscript Accepted: May 15, 2013
Published: June 14, 2013
Juanning Zhao, Xiaona Dong, Limin Gao, and Hongguang Li, "Wedge-plate shear for focus-shifting testing in single-shot laser system," Appl. Opt. 52, 4237-4241 (2013)