Generation of wide-aperture tunable ultraviolet radiation

High-power subnanosecond (0.5 ns) pulses of narrow-band radiation tunable in the 352 nm and 215 nm ranges were obtained. This was possible by combining the highly efficient generation of the harmonics of a wide-aperture (45 mm) neodymium-doped phosphate glass laser with the advantages of a superradiant optical parametric oscillator utilizing KDP crystals. It was found that the profiles of the interacting beams must be formed independently in different channels to achieve efficient summation of the harmonic radiation and the parametric waves.