Temporal compression of nanosecond pulses from a commercial Q-switched Nd:Y
AG laser at second and third harmonic into the sub-nanosecond regime is dem
onstrated. In a geometry consisting of a single cell only, compression in s
everal liquid media is investigated. For both 532 and 355 nm smooth and rel
iable operation is obtained with output pulses as short as 200 ps. A new co
ncept is proposed to separate SBS pulses from the pump beam at low optical
losses.