Abstract

A number of the experimental optical investigations require operating with unpolarized laser beams. But the currently available devices for depolarization of the laser beam (for instance, by means of multiple reflection from a number of variously oriented phase plates) are rather inconvenient. We suggest here a new method of depolarization for the laser radiation which frequently has multimodal structure. This method is based on the phenomenon of nonlinear light depolarization^1–3 that always takes place when the multimodal laser radiation propagates through a nonlinear medium. Due to the multimodal structure of the incident laser radiation, the depolarization is connected with the fact that the polarization parameters depend on the fluctuating intensity of the radiation in nonlinear media. We obtain the partially polarized radiation when the nonlinear relaxation time τ is much less than T, the time of laser intensity correlation.

© 1994 IEEE