All solid state laser source for tunable blue and ultraviolet radiation

Tunable blue and ultraviolet single mode laser light has been generated by frequency quadrupling the output of a semiconductor laser with two successive frequency doubling stages. The laser source is based on a commercial high power semiconductor laser near 972 nm which combines a low power single mode master oscillator with a high power amplifier. The doubling stages consist of nonlinear crystals which are placed inside compact optical buildup resonators. Up to 156 mW tunable blue radiation near 486 nm and 2.1 mW ultraviolet light near 243 nm have been produced.