Abstract

Different authors have studied the spatial profiles of pulses generated in an OPO. For nanosecond OPO such an analysis is difficult since the parametric gain depends both on the pump beam profile and on the longitudinal and transverse modes resonant in the OPO cavity. In an OP A, where no resonant cavity is required, these studies are simpler. Hereafter, we propose a theoretical study of the spatial profile of the beams generated in a femtosecond OP A. We show that when a spatially gaussian pump beam is used, the overall conversion efficiency is limited to about 30 % and that the generated beams profiles have ring like structures.

© 2001 EPS