Patent ID: 7561612

Claim:
A laser source device, comprising: a light source that emits a light beam with a first wavelength; an external resonator that selectively reflects the light beam with the first wavelength towards the light source; a wavelength conversion element that converts a wavelength of a part of the light beam with the first wavelength into a second wavelength different from the first wavelength, the wavelength conversion element being disposed on a first optical path formed between the light source and the external resonator; and an optical path conversion element that guides the part of the light beam converted into the second wavelength to a second optical path different from the first optical path; the light beam with the second wavelength passing through the external resonator; a first laser beam with the second wavelength emitted from the external resonator and a second laser beam with the second wavelength emitted from the optical path conversion element away from the light source being used as an output light beam; and the optical path conversion element including: a selectively reflective film that selectively reflects the light beam with the second wavelength, the selectively reflective film being disposed between the light source and the wavelength conversion element, a reflective surface that reflects the light beam reflected by the selectively reflective film to guide the light beam in a direction substantially the same as the proceeding direction of the first laser beam, and a translucent element that integrates the selectively reflective film and the reflective surface, the translucent element comprising a prism with a first surface, a second surface, and a third surface, the selectively reflective film being disposed on the first surface, the light beam emitted from the light source entering the optical path conversion element from the first surface via the selectively reflective film, and being emitted from the second surface towards the wavelength conversion element, the part of the light beam reflected by the external resonator and proceeding towards the light source that enters the optical path conversion element from the second surface, passes through the first surface, and enters the selectively reflective film, the part of the light beam transmitted through the selectively reflective film proceeding towards the light source, and the part of the light beam reflected by the selectively reflective film being reflected by the third surface, and being emitted from the second surface.