Iodine laser with a controlled pulse duration for nonlinear research

An iodine photodissociation laser (λ = 1.315 μm) with a controlled pulse duration in the microsecond to nanosecond range is described. The output energy was ~ 1 J and the divergence (at half-energy) was 0.1–0.2 mrad. A phase-conjugate stimulated Brillouin scattering mirror was used to obtain pulses of between 40 and 3 ns duration. In this case the output radiation spectrum was almost a "pure" Stokes signal.