Graded reflectance mirrors and phase-unifying mirrors for XeCl lasers

Abstract

Graded reflectance mirrors and phase-unifying mirrors used as output couplers of laser resonators are both intended to improve the output laser beam quality. In the first case one takes advantage of the Gaussian or super-Gaussian profile of the reflected intensity, in the second case the most relevant feature is the ability to cancel out phase variations in the transmitted beam. In this work both types of mirrors are fabricated to be used in an XeCl unstable resonator and the possibility of obtaining graded reflectance mirrors that do not introduce significant phase distortion in the transmitted and reflected beam is demonstrated.