Abstract: A semiconductor laser with a self-sustained pulsation is disclosed in which a first cladding layer of first conductive type, an active layer and a second cladding layer of second conductive type having a striped ridge are formed in that order on a semiconductor substrate of first conductive type. The first and second cladding layers have a refractive index smaller than and a band gap larger than the active layer. A saturable optical absorbing layer having a band gap of energy substantially equal to the energy corresponding to lasing wavelength is formed in both the first and second cladding layers. Further, a barrier layer having a refractive index smaller than and a band gap larger than the first and second cladding layers is formed between the first cladding layer and the active layer and/or between the active layer and the second cladding layer.

Abstract: In a semiconductor laser device comprising an n-type cladding layer, an active layer formed on the cladding layer, a p-type cladding layer formed on the active layer, and a p-type saturable light absorbing layer provided in the p-type cladding layer, the current confinement width for confining current injected into the active layer being W, the thickness d.sub.a of the active layer, the optical confinement factor .GAMMA..sub.a of the active layer, the thickness d.sub.s of the saturable light absorbing layer, the optical confinement factor .GAMMA..sub.s of the saturable light absorbing layer, and the light spot size S on a facet of the semiconductor laser device are so set as to satisfy a predetermined relationship. The reflectivity on a light output facet is set in the range of 10 to 20%.

Abstract: A semiconductor laser with a self-sustained pulsation is disclosed in which a first cladding layer of first conductive type, an active layer and a second cladding layer of second conductive type having a striped ridge are formed in that order on a semiconductor substrate of first conductive type. The first and second cladding layers have a refractive index smaller than and a band gap larger than the active layer. A saturable optical absorbing layer having a band gap of energy substantially equal to the energy corresponding to lasing wavelength is formed in both the first and second cladding layers. Further, a barrier layer having a refractive index smaller than and a band gap larger than the first and second cladding layers is formed between the first cladding layer and the active layer and/or between the active layer and the second cladding layer.

Abstract: A semiconductor laser with a self-sustained pulsation is disclosed in which a first cladding layer of first conductive type, an active layer and a second cladding layer of second conductive type having a striped ridge are formed in that order on a semiconductor substrate of first conductive type. The first and second cladding layers have a refractive index smaller than and a band gap larger than the active layer. A saturable optical absorbing layer having a band gap of energy substantially equal to the energy corresponding to lasing wavelength is formed in both the first and second cladding layers. Further, a barrier layer having a refractive index smaller than and a band gap larger than the first and second cladding layers is formed between the first cladding layer and the active layer and/or between the active layer and the second cladding layer.