Abstract: An optical semiconductor apparatus includes a substrate, a first region formed on the substrate, a second region formed on the substrate, and a stimulating unit. The first region includes a first waveguide which extends in a light propagation direction and is constructed so as to permit light waves in two different polarization modes to be propagated in the propagation direction. The first waveguide contains a first active region which is constructed such that a gain for one of the different polarization modes is dominant. The second region includes a second waveguide which extends in the propagation direction, is coupled to the first waveguide and is constructed so as to permit light waves in the different polarization modes to be propagated in the propagation direction. The second waveguide contains a second active region which is constructed such that a gain for the other of the different polarization modes is dominant.

Abstract: An optical duplexer, configured as a directional coupler, is integrated into an optical coupling arrangement with a fiber optic pigtail, constructed in planar-optical hybrid technology on a substrate (1). To reduce the required surface area and decrease optical cross talk, the branch of the directional coupler (waveguide 6, branch 7) is sharply bent. The bend is equipped with a reflecting mirror (11) integrated opposite the inner edge (10) of the bend. Furthermore, the waveguiding end of the bent branch (7) is equipped with a cylindrical lens. A laser diode (8) is located before this, and a photodiode (5) is located before the angled end of the straight-line integrated waveguide (2).

Abstract: A VCSEL for emitting long wavelength light including a GaAs (111) substrate element, a first mirror stack with mirror pairs in a GaAs/AlGaAs material system lattice matched to a GaInAsN active region with an active structure sandwiched between a first cladding region adjacent the first mirror stack and a second cladding region, the active structure including a nitride based quantum well, and a second mirror stack lattice matched to the second cladding region and having mirror pairs in a GaAs/AlGaAs material system.

Abstract: A semiconductor laser diode, and a method for producing the semiconductor laser diode, includes a waveguide being terminated by a back facet and a front facet and a front facet coating and a back facet coating having a reflectivity providing for controlled decoupling of light at the front facet from the standing lightwave in the waveguide. The front facet coating includes a stack of layers providing for a phase shift of the standing lightwave within the waveguide such that the intensity of the lightwave at the front facet, where the light is decoupled from the standing lightwave, has a relative minimum.

Abstract: The present invention provides a method for selecting a semiconductor integrated optical modulator/laser light source device comprising a modulator section and a laser section. The method comprises the following steps. The laser section is supplied with a direct current which is equal to or larger than a threshold current for allowing the laser section to show a laser emission when the modulator section is supplied with a pulse signal for allowing the modulator section to show a pulse modulation so as to allow a light emitted directly from a facet of the laser section to show a transmission through a light wavelength dispersion medium within which the light on transmission shows a dispersion in wavelength. An intensity of the light having shown the dispersion in wavelength is measured to find a coefficient of variation in intensity of the light, wherein the variation is due to wavelength chirping.

Abstract: A semiconductor laser includes an active layer and a current block structure where a p-type InP layer (a first layer), an n-type InP layer (a second layer), a p-type InP layer (a third layer) and an n-type InP layer (a fourth layer) are laminated, at least one layer selected from a non-doped InP layer, an n-type InP impurity controlled layer and a p-type InP impurity controlled layer being interposed in at least one interface selected from that between the p-type InP layer (the first layer) and the n-type InP layer (the second layer) and that between the n-type InP layer (the second layer) and the p-type InP layer (the third layer); where, the n-type or p-type InP impurity controlled layer is a layer having such an n-type or p-type, respectively, impurity concentration profile in the layer that the impurity concentration continuously decreases from the n-type InP layer (the second layer) side or from the p-type InP layer (the first or the third layer) side, respectively, to the other side until the concentrat

Abstract: A semiconductor laser including a first conductive type of lower clad layer, active layer, a second conductive type of upper first clad layer, the first conductive type of current blocking layer having a stripe shaped open portion, and the second conductive type of upper second clad layer laminated in order on the first conductive type of GaAs substrate, wherein each portion in contact with the lower clad layer, the active layer, the upper first and second clad layer and at least the upper second clad layer of the current blocking layer is composed of a compound semiconductor to be represented by a formula, in which (Al.sub.x Ga.sub.1-x).sub.y In.sub.1-y P (x is 0<x.ltoreq.1 in the lower and upper first, second clad layers, 0.ltoreq.x<1 in the active layer, a given value y is approximately 0.5 for each layer) within of each range of 0<x.ltoreq.0.75 in the portion in contact with the upper second clad layer of the current blocking layer.

Abstract: A diode laser device includes a heat diffusing substrate made from a material that is a good conductor of heat, in one face of which is formed a system of parallel ribs and grooves, the ribs being identical and equidistant, and a plurality of semiconductor arrays incorporating the diodes and housed longitudinally in the grooves. The grooves have an at least approximately triangular cross-section joined to the substrate by one side and each semiconductor array is fixed flat to an oblique flank of one of the ribs.

Abstract: A diffraction grating includes first regions for mainly reflecting first polarized light and second regions for mainly reflecting second polarized light. The first regions and the second regions are alternately arranged in a light propagation direction in a variety of manners to appropriately set its polarization-mode dependency according to need. An optical semiconductor device includes a semiconductor substrate, a laser structure and that diffraction grating formed in the laser structure. The laser structure is a distributed feedback semiconductor laser structure or a distributed Bragg reflector semiconductor laser structure formed on the semiconductor substrate.

Abstract: An optical, semiconductor micro-resonator device includes a microcavity resonator and a pair of adjacent waveguides. The microcavity resonator may be formed as a disk, a ring or closed loop with arbitrarily curved circumference with a diameter of approximately 56000 .lambda..sub.lg /.sub.res or less where .lambda..sub.lg is the longest operating wavelength of light and n.sub.res is the propagating refractive index. A portion of each of the waveguides is disposed adjacent to the microcavity resonator wherein the adjacent portion may be either tangential to the microcavity resonator or curve about a respective portion of the microcavity resonator. Light propagating in the first waveguide with a wavelength on resonance with the microcavity resonator is coupled thereto via resonant waveguide coupling and from the microcavity resonator the light is coupled to the second waveguide for output therefrom.

Abstract: A semiconductor laser is herein disclosed which comprises an active layer 21 and SCH layers which sandwich the active layer 21 from upper and lower sides, wherein the SCH layer comprises a multi-layer structure of 2 or more layers 22,24,23,25, and this multi-layer structure is constituted so that the band gaps of the respective layers may increase as the multi-layer structure is apart from the active layer.

Abstract: A high-power two-dimensional edge-emitting diode laser array comprises mounting modules, laser bars mounted on the modules, and protective caps mounted on the bars opposite the modules. The lasers are electrically connected in series through the modules and caps. The caps serve as laser bar protectors during the bar burn-in. The caps have grooves which compensate for tolerances in the thicknesses of the lasers, modules, and caps. The array is mounted on a base plate, and is in thermal communication with a heat sink. The caps and/or modules are thermal-expansion-matched to the laser bars. Eliminating the need for a wire bond plate allows shortening the modules.

Abstract: A stack of distributed Bragg reflectors is disposed on the surface of a semiconductor substrate. The stack includes a plurality of alternating layers of material having alternating refractive indexes with the stack having a first dopant type. A first cladding region is disposed on the stack with an active area disposed on the first cladding region. The active area includes at least two barrier layers and a quantum well layer. A second cladding region is disposed on the active area with a stack of distributed Bragg reflectors disposed on the cladding region. A contact region is disposed on the second stack of distributed Bragg reflectors. The contact region includes a magnesium doped gallium phosphide material.

Abstract: A semiconductor laser device having light output monitoring light-receiving portion can be fabricated monolithically. A semiconductor laser element (LD) composed of a first cladding layer (22), an active layer (23) and a second cladding layer (24) is formed on a semiconductor substrate (21). A light-receiving portion (PD.sub.1) of a pn junction is formed on the semiconductor substrate (21) disposed behind the semiconductor laser element (LD) by diffusion or selective growth.

Abstract: A p-InP buffer layer is formed on a p-type InP substrate. A selective growth layer consisted of a p-InP clad layer, a SCH-strained MQW layer, and an n-InP clad layer sequentially in stripe form is formed on the buffer layer. On the surface of the buffer layer at both sides of the selective growth portion, a p-InP buried layer, an n-InP blocking layer, a p-InP blocking layer and SCH-MQW carrier recombination layer are selectively grown in the sequential order in a manner that those layer are not grown on the upper surface of the selective growth portion. With burying upper portions of these layers, an n-InP clad burying layer, and an n-InGaAsP contact layer are formed. Then, a surface electrode is formed with covering the entire surface. Also, a back surface electrode is formed on the backside surface of the p-type InP substrate.

Abstract: An optoelectronic module includes one or more VCSEL transmitters and/or photodetectors coincidentally aligned along a common central longitudinal axis. Differing wavelengths of light can be received and transmitted by the optoelectronic module optically coupled to a single optical fiber or in a free-space link. The optoelectronic module is able to receive two wavelengths and transmit one wavelength, or can transmit two wavelengths in the optical link. The VCSEL transmitter can be optically pumped by a vertically integrated pump VCSEL. A parallel optical link supports transmission and reception for each duplex channel on a single optical fiber.

Abstract: A surface-emitting semiconductor light emitting device comprises an n-type ZnSe buffer layer, n-type ZnSSe layer, n-type ZnMgSSe cladding layer, n-type ZnSSe waveguide layer, active layer, p-type ZnSSe waveguide layer, p-type ZnMgSSe cladding layer, p-type ZnSSe layer,p-type ZnSe contact layer, p-type ZnSe/ZnTe MQW layer and p-type ZnTe contact layer, sequentially stacked on an n-type GaAs substrate. A grid-shaped p-side electrode and a Au film convering the p-side electrode are provided on the p-type ZnTe contact layer. An n-side electrode is provided on the back surface of the n-type GaAs substrate. The active layer has a single quantum well structure or a multiple quantum structure including ZnCdSe quantum well layers.

Abstract: A semiconductor laser device is provided which includes a laser diode chip mounted on a sub-mount, a monitor photo diode incorporated in the sub-mount, for monitoring a laser beam emitted by the laser diode chip, a metallic main plate mounting the laser diode chip and the monitor photo diode, an end-face breaking protective layer covering the laser diode chip and the sub-mount; and a seal resin in which the laser diode chip, the monitor photo diode, the end-face breaking preventive layer and at least a portion of the metallic main plate are sealed. In this semiconductor device, a space is provided at a portion of an interface between the end-face breaking preventive layer and the seal resin, which portion is adapted to be irradiated with a monitor laser beam emitted by the laser diode chip, with a light intensity that is not higher than a half of a peak value of the intensity of the monitor laser beam.

Abstract: A semiconductor laser package including a laser chip mounted to an uppermost surface of a leadframe, and a molded structure at least partially encapsulating the laser chip. The laser chip composed of a vertical cavity surface emitting laser and an optional photodetector. The vertical cavity surface emitting laser generating an emission along a path. The molded structure including an optical element positioned a specific distance from an emission aperture of the vertical cavity surface emitting laser. The laser chip and the optical element mounted in precise z-axis alignment from the emission aperture of the vertical cavity surface emitting laser utilizing the uppermost surface of the leadframe as a dimensional reference point.

Abstract: A single cavity mode optoelectronic device, such as a VCSEL, an RCLED or a DFB laser diode, comprises an etched-pillar or mesa structure including an optically active region and strain-applying means in the form of a layer of polymer material having a coefficient of thermal expansion which is greater than that of the optically active region. The layer surrounds the optically active region so as to apply a compressive strain to the latter so as to compensate at least partially for temperature-induced changes in the gain spectrum peak of the optically active region caused by ohmic heating of the device.