Broadly tunable multi-output coherent source based on optical parametric oscillator

An OPO based on KTA and ZGP crystals in tandem is demonstrated to obtain tunable coherent multi-output radiations in the 2.35-7.05 μm range and low threshold of oscillation energy pumped from a Q-switched Gaussian shaped Nd:YAG laser beam with a grating having grooves density of 85 lines/mm. The measured threshold of oscillation energy was 10 μJ. The conversion efficiency and slope efficiency of the ZGP OPO were 32.7% and 34% respectively using a 23 mm long ZGP crystal at 26 mm cavity length.