SPECTRAL CHARACTERISTICS OF UV COHERENT RADIATION GENERATED BY FOUR-WAVE PARAMETRIC PROCESS IN SODIUM VAPOUR

UV coherent radiation at 327 nm, 328 nm, 330 nm and 333 nm is generated by four-wave parametric process in sodium vapour. The spectral characteristics is examined. The signal at 333 mn has narrower line width and wider tunable range. So it is possible to use it as a coherent UV source.