We propose and discuss an optical heterodyne technique to measure the phase retardation of a wave plate. The accuracy of this measurement technique in determining the optical path difference of a quarter-wave plate is of the order of 0.1 nm, thus exceeding the accuracy of other measurement techniques.
© 1988 Optical Society of America
Lin Yao, Zhou Zhiyao, and Wang Runwen, "Optical heterodyne measurement of the phase retardation of a quarter-wave plate," Opt. Lett. 13, 553-555 (1988)