Generation of frequency-controlled nanosecond and picosecond optical pulses by high-gain parametric amplification

An ADP parametric amplifier pumped by the 266-nm fourth harmonic of
Q
-switched or mode-locked Nd lasers has been used to produce nanosecond or picosecond pulses at a number of wavelengths across the visible spectrum. The input signal to the parametric amplifier was obtained either from pulsed parametric fluorescence passed through a Fabry-Perot (FP) filter, or from CW noble gas lasers. Peak powers to 60 kW and pulse lengths of the order of 10 ps have been generated by amplifying the beam from a CW He-Ne laser.