| 摘要 |
PROBLEM TO BE SOLVED: To provide a wavelength conversion device allowing a high-output UV laser device to reduce staining of an outer surface of a light emitting window in such a way that a beam diameter of wavelength-converted higher harmonics laser light is enlarged by a beam diameter-enlarging unit in a high-output UV laser device.SOLUTION: A laser oscillator 1 emits fundamental wave laser light L0 with a predetermined beam diameter, and the fundamental wave laser light L0 is emitted in a crystal sealing cell 2 from an incidence window 3 provided on one end in the longitudinal direction of a casing. The wavelength of the incident fundamental laser light L0 is converted into third harmonic wave laser light L2 by an SHG crystal 5 and a THG crystal 6. The converted third harmonic wave laser light of which wavelength has been converted passes through a spectral mirror 7, and then unnecessary waves are dispersed. The beam diameter of the third harmonic wave laser light L2 having passed through the spectral mirror 7 is enlarged at a beam diameter enlarging part 8, and the third harmonic wave laser light L2 is made into third harmonic wave laser light L4. The third harmonic wave laser light L4 is emitted as harmonic laser light of which wavelength has been converted, from a light emission window 4 provided at the other end in the longitudinal direction of the casing of the crystal sealing cell 2. |
