Second-harmonic generation device and method of producing the same and second-harmonic generation apparatus and method of producing the same

摘要

A second harmonic generation device has a waveguide layer for generating and outputting a second harmonic wave ray in response to the laser light from a laser, wherein the returning of reflected laser light from the waveguide layer to a laser is prevented. The returning of reflected laser light is prevented: by inclining a normal of at least one of a first and second end facets of the waveguide layer from an optical axis of the laser; by providing an absorbing layer on the waveguide layer for absorbing waveguided laser light and for waveguiding the generated second harmonic wave ray; or by providing a second waveguide layer for waveguiding and outputting the generated second harmonic wave ray and for radiating the waveguided laser light. The absorbing layer is provided by a blue filter adhered or deposited on the top surface of the waveguide layer. The second waveguide layer is provided by making the second waveguide layer more narrow that the waveguide layer. A second harmonic generation apparatus includes the laser. Methods of producing these devices and apparatus are disclosed.