Wavelength switching in the acceptance bandwidth of a dual injection seeded optical parametric oscillator

Abstract

We describe the investigation of a dual laser injection seeding and switching of an optical parametric oscillator. This option is part of a differential absorption lidar (DIAL) transmitter system for measuring environmental species at two wavelengths. For instance the realization was accomplished by using an injection seeded diode pumped Nd:YAG laser as pump for an optical parametric oscillator (OPO). The purpose of these studies was an evaluation of different injection seeding techniques and their practical applicability. The suitable wavelengths were generated by injection seeding the OPO at the signal wavelength. Experiments with one and two external cavity diode lasers were performed to generate the required two idler wavelengths for the measurement. By this method line-narrowing occurs. A spectral width of the pulsed OPO of 200 MHz was achieved. Within the seeding and switching range at these two wavelengths inter-mode mixing was observed.