HIGHER HARMONIC GENERATOR, LASER ANNEALING DEVICE, AND HIGHER HARMONIC GENERATING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a higher harmonic generator which enables enhancement of the wavelength conversion efficiency. SOLUTION: A laser light source emits a laser beam. The laser beam emitted from the laser light source impinges on a wavelength conversion element, which has an incidence surface and an exit surface on the side opposite to the incidence surface, from the incidence surface. The wavelength conversion element emits a higher harmonic beam obtained by converting the wavelength of the impinging laser beam and the wavelength non-converted beam from the exist surface. A feedback optical system causes the wavelength non-converted beam emitted from the exist surface of the wavelength conversion element to impinge on the wavelength conversion element from its incidence surface.