Generation Of Tunable Mid-Ir (1.8-2.4 Μm) Laser From Optical Parametric Oscillation In Ktp

We report the first demonstration of a tunable mid-IR (1.8-2.4 μm) coherent source based on optical parametric oscillation (OPO) in a KTP crystal pumped by a Nd: YAG (1064 nm) laser. The phase matching of bixial crystals, OPO gain and threshold energy are discussed for the improvement of efficiency. The tuning range and efficiency are measured at various pumping energies and cavity lengths. OPO tuning curves at various pumping wavelengths (1.064, 1.32 and 1.54 μm) are also calculated. © 1990