2 W Cw Opo In Mid-Ir Pumped By Opsl Laser Intra-Cavity Radiation.

The design and experimental testing of an Optical Parametric Oscillator generating 2 Watts of continuous wave radiation at 3.5 micron is presented.The oscillator uses a KTA (Potassium Titanyl Arsenate) crystal as the nonlinear medium, pumped by the 1.06 mm intracavity radiation of an Optically Pumped Semiconductor Laser (OPSL).A review of the nonlinear characteristics of KTA is presented, and design criteria for the OPSL intra-cavity pumped OPO are given.The experimental results are presented and discussed.