Patent ID: 7027209
Filing Date: 2006-04-11
Classification: G02F

Abstract:
1. An optical resonant frequency converter for a light wave, comprising: a ring resonator which includes a first mirror, a second mirror and a non-linear crystal with an entry surface and an exit surface which are so arranged that the light wave passes into the non-linear crystal in the form of a first laser beam through the entry surface and issues therefrom again through the exit surface, wherein the light wave is partially converted in the non-linear crystal from the first laser beam into a second laser beam of a different frequency, wherein a normal to the entry surface is approximately at the Brewster angle relative to the light wave incident into the crystal and the incident light wave is polarised parallel to a plane of the ring resonator, wherein the exit surface is antireflectively coated both for the frequency of the first and also the second laser beam and wherein the normal to the exit surface is at an angle of less than 15 degrees relative to the light wave issuing from the crystal.