Abstract: An injection laser comprises a laser heterostructure, at least one radiation inflow region adjoining the laser heterostructure, and reflectors that together form an optical resonator. The laser heterostructure comprises an active layer, cladding layers, and ohmic contacts. The radiation inflow region adjoining the laser heterostructure is transparent to the laser radiation and is located on at least one side of the active layer. The radiation inflow region additionally includes at least one optical facet, an outer surface, and an inner surface. Radiation generated in the active layer flows into the radiation inflow region and exits the laser.

Abstract: A semiconductor optical amplifier includes a master source of input radiation, an amplifying component optically coupled to the master source. The amplifying component includes a semiconductor heterostructure that includes an active layer positioned between two cladding layers and an ohmic contact formed to at least one sublayer of the semiconductor heterostructure. The amplifying component also includes an input-output region for radiation that comprises at least one additional layer on at least one side of the heterostructure. This additional layer adjacent to the heterostructure comprises one or more sublayers having refractive indices nIORq and optical loss factors &agr;IORq (cm−1) selected to provide for enhanced output power and a reduced angle of divergence.

Abstract: An injection incoherent emitter outputs a directed beam of light resulting from spontaneous emission. The emitter provides small divergence angles and enhanced external efficiency, as well as increased energy and light power. Specific ranges of compositions and thicknesses for layers and sublayers in the entire heterostructure, as well as for the layers of the emission output area may be employed to create this emitter. Different embodiments for the heterostructure and output areas permit emission from the emitters in different but controllable directions. One such direction is perpendicular to the active layer. Other embodiments include multibeam incoherent emitters, including embodiments that emit from lines and arrays of emitters, wherein each emitter has an independently controllable beam.