Patent ID: 9203204
Filing Date: 2015-12-01
Classification: G02F,H01S

Abstract:
1. An apparatus for generating laser radiation at a frequency multiplied as compared with a base frequency, comprising (a) an optical resonator, in which input laser radiation ( (b) at least one conversion element through which the input laser radiation circulating in the optical resonator radiates, wherein the at least one conversion element converts the input laser radiation, at least in part, into output laser radiation at the multiplied frequency; and (c) at least one compensation element, through which the input laser radiation circulating in the optical resonator also radiates, wherein the at least one compensation element absorbs the input laser radiation, in part, and balances out a temperature-dependent variation of an optical path length of the input laser radiation in the at least one conversion element, at least in part; wherein the at least one conversion element and the at least one compensation element are non-linear optical crystals; wherein the at least one conversion element and the at least one compensation element comprise the same material; wherein the input laser radiation radiates through the at least one conversion element and the at least one compensation element from different directions, relative to crystal axes of the non-linear optical crystals; and wherein the at least one compensation element has a first temperature-dependent variation of an optical path length of the input laser radiation that radiates through the at least one compensation element, wherein the first temperature-dependent variation is directed counter to a second temperature-dependent variation of the optical path length of the input laser radiation that radiates through the at least one conversion element.