An arrangement (10) for efficiently generating tunable pulsed laser output
at 8-12 microns. The arrangement (10) includes a laser (12), a first
optical parametric oscillator (14) of unique design, and a second optical
parametric oscillator (22). The first oscillator (14) is constructed with
an energy shifting crystal (20) and first and second reflective elements
(16) and (18) disposed on either side thereof. Energy from the laser (12)
at a first wavelength is shifted by the crystal and output at a second
wavelength. The second wavelength results from a secondary process induced
by a primary emission of energy at a third wavelength, the third
wavelength resulting from a primary process generated from the first
wavelength in the crystal. Mirror coatings are applied on the reflective
elements (16 and/or 18) for containing the primary emission and enhancing
the secondary process. The second optical parametric oscillator (22) then
shifts the energy output by the first OPO (14) at the second wavelength to
the desired fourth wavelength.
