US 7,010,006 B2 · Light source apparatus and its control method

Abstract

A light source device can attain a stable output of a harmonic even when there occurs a change in the ambient temperature or fluctuation in the output power. The light source device is provided with a semiconductor laser source (4), an optical waveguide-type QPM-SHG device (5) for generating a second harmonic from light emitted from the semiconductor laser source (4), a wavelength control means (7) for controlling a wavelength of light emitted from the semiconductor laser source (4), a means for slightly fluctuating wavelength (8) for changing a wavelength of light emitted from the semiconductor laser source (4) and a means for detecting a change in output light power of the optical waveguide-type QPM-SHG device (5) that occurs when a wavelength of light emitted from the semiconductor laser source (4) is changed. In this case, a wavelength of light emitted from the semiconductor laser source (4) is controlled to an optimum wavelength of the optical waveguide-type QPM-SHG device (5) based on a change in output light power of the optical waveguide-type QPM-SHG device (5) that occurs when a wavelength of light emitted from the semiconductor laser source (4) is changed.

Claims15

Dependent claims

A light source device comprising:

a semiconductor laser source;
a second harmonic generation device for generating a second harmonic from light emitted from the semiconductor laser source;
a means for controlling output light power of the semiconductor laser source in such a manner that a power of the second harmonic emitted from the second harmonic generation device is constant;
a means for controlling a wavelength of light emitted from the semiconductor laser source;
a means for periodically changing the wavelength of light emitted from the semiconductor laser source;
and
a means for detecting a change in output light power of the semiconductor laser source or a change in an amount of a current injected into the semiconductor laser source that occurs when the wavelength of light emitted from the semiconductor laser source is periodically changed,
wherein the wavelength of light emitted from the semiconductor laser source is controlled to an optimum wavelength of the second harmonic generation device based on the change in output light power of the semiconductor laser source or the change in the amount of the current injected into the semiconductor laser source that occurs when the wavelength of light emitted from the semiconductor laser source is periodically changed.

5 more elements

Dependencies are inferred from the claim text.

Light source apparatus and its control method

Life of this patent

Light source apparatus and its control method

Life of this patent

Abstract

Claims15