A cw optical parametric oscillator for sub-ppb trace gas detection in the 3 /spl mu/m region

The optical parametric oscillator (OPO) is an all-solid-state laser system able to combine high output power, small linewidth and spectral coverage with very good frequency tuning potential. The continuous-wave, pump-resonant, singly-resonant optical parametric oscillator (cw-PR-SRO) uses periodically poled lithium niobate (PPLN) as nonlinear medium.