Mid-IR CW Cr:ZnS laser tunable with acousto-optical filter

We report on CW, acousto-optically tuned Cr:ZnS mid-IR laser operating over 1890 - 2785 nm spectral range with 40% slope efficiency with respect to the pump power in the maximum of tuning curve. The tuning range over 1890 - 2785 nm was demonstrated by tuning the radio frequency (RF) applied to a TeO2 acousto-optical filter between 30.3 MHz and 20.12 MHz. A maximum output power of 2.8 W was achieved at 2.23 μm under 10.7 W of pump power. The linewidth of the Cr:ZnS laser measured at central wavelength was < 0.8 nm.