An investigation was made of superluminescent optical parametric oscil
lators generating visible light when ADP and KDP crystals were pumped
with the third and fourth harmonics of a neodymium laser. The conversi
on efficiency was 70% and the output energy in the form of parametric
waves was 0.35 J. The advantages of the third harmonic of a neodymium
laser as the pump radiation, over the fourth harmonic, were demonstrat
ed.