摘要:
A semiconductor laser device and module for use in a dense wavelength division multiplexed optical communications system are shown. The laser device preferably has cavity lengths greater than 1000 &mgr;m, and compressive strain multi-quantum well active layer, and front-facet reflectivity of less than about 4%. Higher optical outputs and longer cavity lengths are achieved. Preferred modules use these laser diodes with external wavelength-selective reflectors that have narrow bandwidths of 3 nm or less, and which include a plurality of longitudinal mode subpeaks within the bandwidth. Relationships between reflectivity value of the front facet and the peak reflectivity of the wavelength-selective reflector for long cavity length laser device are also disclosed, with the relationships providing higher output power along with a stabilized output spectrum.
摘要:
A semiconductor laser device and module for use in a dense wavelength division multiplexed optical communications system are shown. The laser device preferably has cavity lengths greater than 1000 μm, and compressive strain multi-quantum well active layer, and front-facet reflectivity of less than about 4%. Higher optical outputs by longer cavity lengths are achieved. Preferred modules use these laser diodes with external wavelength-selective reflectors that have narrow bandwidths of 3 nm or less, and which include a plurality of longitudinal mode subpeaks within the bandwidth. Relationships between reflectivity value of the front facet and the peak reflectivity of the wavelength-selective reflector for long cavity length laser device are also disclosed, with the relationships providing higher output power along with a stabilized output spectrum.
摘要:
A semiconductor laser device having two active-layer stripe structures includes an n-InP substrate, an n-InP clad layer, a lower GRIN-SCH layer, an active layer, an upper GRIN-SCH layer, a p-InP clad layer, and a p-InGaAsP contact layer grown in this order, in a side cross section cut along one of the stripe structure. A high-reflection film is disposed on a reflection-side end surface, and a low-reflection film is disposed on an emission-side end surface. A p-side electrode is disposed on only a part of the upper surface of the p-InGaAsP contact layer so that a current non-injection area is formed on an area absent the p-side electrode.
摘要:
A single semiconductor laser device used in a semiconductor laser module of an optical amplifier and having a first light emitting stripe with a diffraction grating and at least one other light emitting stripe with a diffraction grating and which are aligned to respectively emit a first laser beam and at least one other laser beam through one edge surface.
摘要:
In the semiconductor laser device of the present invention, a semiconductor stacked structure including an active layer comprising a strained multi-quantum well structure is formed on a substrate 1, a cavity length is larger than 1000 &mgr;m but equal to or smaller than 1800 &mgr;m, and a low-reflection film S1 having a reflectance of 3% or less is formed on one facet and a high-reflection film S2 having a reflectance of 90% or more is formed on the other facet. The semiconductor laser module has a structure in which the semiconductor laser device is set to a cooling device constituted by electrically alternately arranging 40 pairs or more of the Peltier elements and holding them by top and bottom ceramic plates and sealed in the package. A grating having a reflection bandwidth of 1.5 nm or less is formed on an optical fiber to be built in.
摘要:
A semiconductor laser module includes a single semiconductor laser device having a first light emitting stripe and at least one other light emitting stripe which are aligned to respectively emit a first laser beam and at least one other laser beam through one edge surface. It also includes a first lens positioned so that the first laser beam and the at least one other laser beam emitted from the semiconductor laser device are incident thereon, the first lens configured to separate the first laser beam and the at least one other laser beam. A beam synthesizing member is included and has a first input part on which the first laser beam is incident, at least one other input part on which the at least one other laser beam is incident, and an output part from which the first laser beam emerging from the first input part and the at least one other laser beam emerging from the at least one other input part are multiplexed and emitted as a multiplexed laser beam. An optical fiber is positioned to receive the multiplexed laser beam therein.
摘要:
An n-Inp buffer layer, a GRIN-SCH-MQW active layer, and a p-InP spacer layer are laminated on an n-InP substrate. A p-InP blocking layer and an n-InP blocking layer are provided to be adjacent to an upper region of the n-InP buffer layer, the GRIN-SCH-MQW active layer and the p-InP spacer layer. A p-InP cladding layer, a p-GaInAsP contact layer, and a p-side electrode are laminated on the p-InP spacer layer and the n-InP blocking layer, and an n-side electrode is arranged on a rear surface of the n-InP substrate. A diffraction grating that selects light having the number of oscillation longitudinal modes of not less than 10, more preferably not less than 18, oscillation longitudinal modes the difference values of which in optical intensity from the oscillation longitudinal mode having the highest optical intensity are not more than 10 dB, is arranged in the p-InP spacer layer.
摘要:
A semiconductor laser device which has a diffraction grating partially provided in the vicinity of an active layer formed between a radiation-side reflection film provided on a radiation-side end surface of a laser beam and a reflection film provided on a reflection-side end surface of the laser beam, and which outputs a laser beam having a desired oscillation longitudinal mode based on a wavelength selection characteristic of at least the diffraction grating. The diffraction grating is formed in isolation with an isolation distance of Ls=15 μm from the radiation-side reflection film.
摘要:
A diffraction grating is provided in the vicinity of a GRIN-SCH-MQW active layer formed between a radiation side reflection coating provided on a radiation end face of a laser beam and a reflection coating provided on a reflection end face of the laser beam, and on the radiation side reflection coating side. An n-InP layer which covers the upper part of the diffraction grating is also provided, so that the current from the p-side electrode is prevented from being injected to the vicinity of the diffraction grating by the n-InP layer. An n-InPGaAsP diffusion prevention layer forms a non-current injection area so as to suppress alloying with the p-side electrode.
摘要:
A semiconductor laser device including a light reflecting facet positioned on a first side of the semiconductor device, a light emitting facet positioned on a second side of the semiconductor device thereby forming a resonator between the light reflecting facet and the light emitting facet, and an active layer configured to radiate light in the presence of an injection current, the active layer positioned within the resonator. A wavelength selection structure is positioned within the resonator and configured to select a spectrum of the light including multiple longitudinal modes, the spectrum being output from the light emitting facet. Also, an electrode positioned along the resonator and configured to provide the injection current, and a tuning current that adjusts a center wavelength of the spectrum selected by the wavelength selection structure.