A laser light-source apparatus includes; a seed light source; a fiber amplifier configured to amplify pulse light output from the seed light source based on gain switching; a solid state amplifier configured to further amplify the resultant pulse light; a nonlinear optical element configured to perform wavelength conversion on the pulse light output from the solid state amplifier; an optical switching element that is disposed between the fiber amplifier and the solid state amplifier and is configured to remove ASE noise; and a control unit. The control unit is configured to control the optical switching element in such a manner that propagation of light is permitted in an output period of the pulse light from the seed light source, and is stopped in a period other than the output period.

A laser system includes a nonlinear optical (NLO) crystal, wherein the NLO crystal is annealed within a selected temperature range. The NLO crystal is passivated with at least one of hydrogen, deuterium, a hydrogen-containing compound or a deuterium-containing compound to a selected passivation level. The system further includes at least one light source, wherein at least one light source is configured to generate light of a selected wavelength and at least one light source is configured to transmit light through the NLO crystal. The system further includes a crystal housing unit configured to house the NLO crystal.

A method and a laser for breaking through the limitation of fluorescence spectrum on laser wavelength is disclosed. The method includes: exciting electrons to a high energy level by pump light, and suppressing an oscillation of radiation light by laser cavity coating, using a laser resonance to enhance a transition probability of an electron-phonon coupling from the high energy level to a multi-phonon coupling level, so as to realize the emission and enhancement of breakthrough fluorescence spectrum and realize the radiation light oscillation, wherein the laser cavity includes an incident mirror, a folding mirror, a tuning element and an exit mirror arranged in sequence along an optical path direction, the laser gain medium is located between an incident mirror and a folding mirror in the laser resonator, and the tuning element is arranged in the laser cavity at a Brewster angle.

A laser system includes a pumping laser apparatus configured to output pumping light having a first wavelength; a signal laser apparatus configured to output signal light having a second wavelength longer than the first wavelength; an optical parametric crystal configured to transmit the pumping light and the signal light and output amplified light having the second wavelength; and a photon flux density control mechanism configured to control photon flux densities of the pumping light and the signal light in such a way that a sum of the photon flux densities of the pumping light and the signal light at an input end of the optical parametric crystal causes an intensity distribution of the amplified light having the second wavelength to be an intensity distribution that monotonously decreases from a center of the intensity distribution toward a periphery thereof.