ULTRAVIOLET RAY LASER DEVICE

PROBLEM TO BE SOLVED: To provide an ultraviolet ray laser device for generating ultraviolet ray laser beams efficiently and greatly stabilizing wavelength. SOLUTION: An ultraviolet ray laser device has a laser light source 21 with a wave consisting of a wavelength which is double that of Nd: YAG laser, an iodine absorption cell TC inside, and a nonlinear crystal 22 for generating a wave consisting of a wavelength which is double the fundamental wave and generates ultraviolet ray laser beams by a ring-type external resonator 20. At this time, the resonator length of the ring-type external resonator 20 is controlled so that the light frequency of the fundamental wave and the resonator frequency of the external resonator match and at the same time the resonator length of the laser light source 21 is controlled so that the wavelength of the fundamental wave can be included within the uniform width of the absorption spectrum of an iodine molecule.