Interferometers based on conjugate-wave generation using three- and four-wave mixing are described theoretically. They are shown to be self-referencing and sensitive to small changes in the phase front.
© 1980 Optical Society of America
Frederic A. Hopf, "Interferometry using conjugate-wave generation," J. Opt. Soc. Am. 70, 1320-1323 (1980)