Electrooptic switch for unpolarized radiation in a laser with intracavity second harmonic generation in crystals exhibiting the aperture effect

The average output power of the second harmonic can be increased and the construction of a laser can be simplified by using a nonlinear crystal not only for second harmonic generation, but also as an electrooptic switch for the separation of rays with different polarizations at the fundamental frequency. By way of example, the results are given of a continuously pumped YAG laser in which a switch for unpolarized radiation is in the form of a Pockels cell and a nonlinear lithium iodate crystal cut at an angle of 29° to the optic axis. It was found that such a laser configuration could ensure 77% conversion of the fundamental frequency radiation to the second harmonic at the wavelength of 0.53 μ and with an average power of 2.4 W.