Patent ID: 6845117
Filing Date: 2005-01-18
Classification: H01S

Abstract:
1. A semiconductor laser device comprising: a first conductive-type semiconductor substrate; a first conductive-type semiconductor buffer layer laminated on the semiconductor substrate; an active layer laminated on the semiconductor buffer layer; a first electrode laminated above the active layer; a second electrode disposed on the bottom surface of the semiconductor substrate; a second conductive-type spacer layer laminated between the active layer and the first electrode; a first diffraction grating embedded in one area in the second conductive-type spacer layer and possessing the ability to select a wavelength of a laser beam having a first center wavelength; and a second diffraction grating embedded in another area in the second conductive-type spacer layer and possessing the ability to select a wavelength of a laser beam having a second center wavelength, wherein the laser beam having the first center wavelength and the laser beam having the second center wavelength have a plurality of longitudinal oscillation modes.