Solid-state laser device capable of producing an outgoing laser beam having a narrower spectral band width

Abstract

In a solid-state laser device for producing an outgoing laser beam having a waveband of near infrared radiation that is represented by a specific wavelength of, for example, 0.85 .mu.m, the solid-state laser device comprises a semiconductor laser device for producing an excitation laser beam having an excitation wavelength of, for example, 806 nm. By the excitation laser beam, a first laser medium such as a self-frequency doubling crystal produces a first laser beam having a first wavelength of, for example, 0.5315 .mu.m. The first wavelength is equal to a wavelength of a second harmonic of the first laser medium is shorter than the specific wavelength. Excited by the first laser beam, a second laser medium such as an Er:LiYF.sub.4 crystal produces a second laser beam having a second wavelength equal to the specific wavelength. The solid-state laser device thereby produces the second laser beam as the outgoing laser beam. The solid-state laser device further comprises a nonlinear optical crystal for converting the outgoing laser beam into a converted laser beam having a wavelength of 0.425 .mu.m. A Q-switching element may be disposed between the first and the second laser media. The self-frequency doubling crystal may be Nd.sub.x Y.sub.1-x Al.sub.3 (BO.sub.3).sub.4 crystal.

Dependencies are inferred from the claim text.