Abstract: A semiconductor laser apparatus comprises a light-emitting portion including a light-emitting device for outputting a laser beam, a light-receiving element for receiving the laser beam outputted from said light-emitting device, a wavelength monitoring portion including an optical system disposed between said light-emitting device and said light-receiving element, a control portion for controlling the wavelength of the laser beam outputted from said light-emitting device by controlling the temperature of said light-emitting device based on the wavelength of the laser beam detected by said wavelength monitoring portion, an optical isolator disposed on the optical path between said light-emitting device and said wavelength monitoring portion for preventing the light from returning from said wavelength monitoring portion back to said light-emitting device, and a temperature regulating portion for independently controlling the temperatures of said light-emitting portion and wavelength monitoring portion.

Abstract: A semiconductor laser apparatus comprises a light-emitting portion including a light-emitting device for outputting a laser beam, a light-receiving element for receiving the laser beam outputted from said light-emitting device, a wavelength monitoring portion including an optical system disposed between said light-emitting device and said light-receiving element, a control portion for controlling the wavelength of the laser beam outputted from said light-emitting device by controlling the temperature of said light-emitting device based on the wavelength of the laser beam detected by said wavelength monitoring portion, an optical isolator disposed on the optical path between said light-emitting device and said wavelength monitoring portion for preventing the light from returning from said wavelength monitoring portion back to said light-emitting device, and a temperature regulating portion for independently controlling the temperatures of said light-emitting portion and wavelength monitoring portion.

Abstract: A semiconductor laser apparatus comprises a light-emitting portion including a light-emitting device for outputting a laser beam, a light-receiving element for receiving the laser beam outputted from said light-emitting device, a wavelength monitoring portion including an optical system disposed between said light-emitting device and said light-receiving element, a control portion for controlling the wavelength of the laser beam outputted from said light-emitting device by controlling the temperature of said light-emitting device based on the wavelength of the laser beam detected by said wavelength monitoring portion, an optical isolator disposed on the optical path between said light-emitting device and said wavelength monitoring portion for preventing the light from returning from said wavelength monitoring portion back to said light-emitting device, and a temperature regulating portion for independently controlling the temperatures of said light-emitting portion and wavelength monitoring portion.

Abstract: There is provided a high-quality semiconductor laser device having a current confinement feature along with a method of manufacturing the same in a simple manner. The upper clad layer 4 of a semiconductor laser device is a semiconductive layer made of a compound of elements of the III and V groups doped with an amphoteric impurity substance and the electric resistance of the lateral slopes is greater on the top of the mesa than on the upper clad layer 4 of the mesa. A method of manufacturing a semiconductor laser device comprises a step of repeating a cycle of crystal growth operation of sequentially forming a layer of an element of the III group, a layer of an amphoteric impurity substance and a layer of an element of the V group on said substrate by means of an MBE technique to produce said upper clad layer made of a compound of elements of the III and V groups.