Simultaneous multiple line optical parametric oscillators based on periodically-poled lithium niobate

Coherent sources emitting in the mid-infrared (2-5µm) spectral region have received increasing interest over the last few years owing to numerous applications. Optical Parametric Oscillators, pumped by reliable diode-pumped solid-state lasers, offer an attractive route to these wavelength regions, providing enormous flexibility in the choice of operating wavelength. Although widely tunable, the emission linewidth of OPOs is often rather narrow (typically a few nm) limited by factors such as the phase-matching bandwidth of the crystal. For some applications, a broadband or multiple wavelength output spanning a much wider spectral region is desirable