Simple phase-shifting method in a wedge-plate lateral-shearing interferometer.
A simple phase-shifting method in a wedge-plate lateral shearing interferometer is described. Simply moving the wedge plate in an in-plane parallel direction gives the amount of phase shift required for phase-shifting interferometry because the thickness of a wedge plate is not constant and varies along the wedge direction. This method requires only one additional linear translator to move the wedge plate. The required moving distance for a phase shift of the wave front with this method is of the order of a millimeter, whereas the typical moving distance for another method that uses a piezoelectric transducer is of the order of a wavelength. This method yields better precision in controlling the moving distance than do the other methods.
Photometry & Imaging Optics Group, Korea Research Institute of Standards and Science, P.O. Box 102, Yusong, Daejeon, 305-600, Korea. jsong@kriss.re.kr
Jae Bong
JB
Song
Yun Woo
YW
Lee
In Won
IW
Lee
Yong-Hee
YH
Lee