Continuous Wave Mid--Infrared Optical Parametric Oscillator

Lightwave Electronics Corporation proposes to develop technology for medium power, continuous wave optical parametric oscillators (OPOs). We will investigate techniques to scale our existing laboratory OPO from its present 2.5 watt power level at 3.4um to the ten watt level. This OPO is pumped with 13 watts from a 1064 nm. laser diode pumped Nd:YAG laser, is singly resonant at the 1.54 pm signal, and uses periodically poled iiNbO3 (PPLN) as the nonlinear crystal. Pump energy depletion is an amazing 85%. To obtain higher OPO outputs in the 3-5 micron range, the PPLN needs to be scaled to larger thickness so that the average power density of our present unit can be maintained. Also, if we can drive the OPos with multi- transverse mode Nd:YAG lasers and sufficiently maintain the OPOs' spectral and spatial beam qualities then the resulting mid-infrared source will be simpler, more efficient, and hence less costly than if we used a single-transverse mode drive Nd:YAG laser. Therefore, the Phase I program will concentrate on poling thicker PPLN crystals and building and characterizing a cw singly resonant OPO with A multi-mode pump laser. The Phase II goal is to build a cw OPO using a 50 watt Nd:YAG laser and pumping an OPO that can deliver up to 10 watts over a large portion of the 3-5 micron wavelength range.