Intracavity difference frequency generation using dual-wavelength oscillation by an electronically tuned Ti : sapphire laser

Tunable mid-infrared radiation was generated by difference frequency mixing in a MgO:LiNbO3 crystal placed in a dual wavelength Ti:sapphire laser cont rolled with an acousto-optical device. A wavelength range from 2.77 to 5.04 mu m was demonstrated by tuning the pump pulse of a longer wavelength in c oupling with the rotation of the mixing crystal, while the shorter waveleng th pulse was fixed at three selected wavelengths of 703, 711 or 719 nm. The maximum average power was 250 mu W and the fluctuation was +/-10% at 3.05 mu m.