High Efficiency, Eye-Safe KTP OPO

An Optical Parametric Oscillator (OPO) employing Potassium Titanyl Phosphate (KTP) as nonlinear crystal is operated as an eye-safe source at 1.58 ~m. With a Q-switched Nd : YAG pump laser emitting at 1.064 ~m, a total conversion efficiency of 35 % to 1.58 ~m is obtained. Results on KTP OPO are compared with similar measurements on LiNb0 3 OPO.