Abstract: A beam alignment chamber extending in a length direction comprising a base having a front edge, and two side edges, first and second opposed side walls connected to the base, and extending along the length of the base, a front wall located at the front edge of the base having an output opening. The beam alignment chamber further comprises a plurality of arrays of light sources disposed to direct light beams through the first or second side walls, and a plurality of reflectors mounted on the base, each having independent yaw and pitch adjustments, each reflector being paired with a corresponding array of light sources, the base-mounted reflectors being disposed to direct the light beams along the length of the beam alignment chamber through the output opening forming an aligned two-dimensional array of parallel light beams.

Abstract: A laser diode capable of independently driving each ridge section, and inhibiting rotation of a polarization angle resulting from a stress applied to the ridge section without lowering reliability and a method of manufacturing the same are provided. A laser diode includes: three or more strip-like ridge sections in parallel with each other with a strip-like trench in between, including at least a lower cladding layer, an active layer, and an upper cladding layer in this order; an upper electrode on a top face of each ridge section, being electrically connected to the upper cladding layer; a wiring layer electrically connected to the upper electrode, in the air at least over the trench; and a pad electrode in a region different from regions of both the ridge section and the trench, being electrically connected to the upper electrode through the wiring layer.

Abstract: The invention relates to a diode laser array with at least one laser bar and having at least one emitter and a heat sink array for cooling the at least one laser bar.

Abstract: A laser light source apparatus includes a first laser array light source that emits first-wavelength light, and a second laser array light source that emits second-wavelength light, the second wavelength being different from the first wavelength. The first laser array light source includes a first fundamental wave laser array that produces first fundamental wave light having a first original wavelength, and a first wavelength conversion element that wavelength-converts the first fundamental wave light into the first-wavelength light. The second laser array light source includes a second fundamental wave laser array that produces second fundamental wave light having a second original wavelength different from the first original wavelength, and a second wavelength conversion element that wavelength-converts the second fundamental wave light into the second-wavelength light.

Abstract: This semiconductor laser apparatus includes a base having a step portion, a first upper surface on a lower side of the step portion and a second upper surface on an upper side of the step portion, a first semiconductor laser device bonded onto the first upper surface, having a first light-emitting region on an upper side thereof, and a second semiconductor laser device bonded onto the second upper surface, having a second light-emitting region on a lower side thereof. The first light-emitting region is located above the second upper surface in a state where the base is horizontally arranged.

Abstract: In one of the embodiments, a dark channel array is provided which includes gain channels, each configured to emit an output beam from an output surface and to have a light wave propagating therethrough. It further includes a dark channel configured to emit an output beam from the output surface of the dark channel array and to have a light wave propagating in the dark channel, such that output beams from the plurality of gain channels are coherently coupled in phase with each other. The dark channel array is configured such that the dark channel captures a portion of the output beam from at least two of the plurality of gain channels by radiant coupling.

Abstract: This invention relates to a side-emitting light device comprising two sub-assemblies which are optically bonded together. Each sub-assembly comprises a substrate, at least one light source disposed on the substrate, and a luminescent plate optically bonded with the at least one light source. The light source emits light of a wavelength capable of exciting luminescence light from the luminescent plate. The two sub-assemblies are arranged having the free surface of the luminescent plates facing each other. The side-emitting light device is for instance applicable for light sources comprising naked dies arranged with Thin Film Flip Chip (TFFC) technique or laser diodes.

Abstract: A multibeam laser diode capable of improving heat release characteristics in the case of junction-down assembly is provided. Contact electrodes are provided respectively for protruding streaks of a laser diode device, and pad electrodes are provided to avoid the protruding streaks and the contact electrodes. The contact electrodes and the pad electrodes are connected by wiring electrodes, and the contact electrodes are covered with a first insulating film. Thereby, electric connection is enabled without straightly jointing the contact electrodes to a solder layer. A heat conduction layer configured of a metal is provided on the first insulating film, the heat conduction layer is jointed to the solder layer, and thereby the heat release characteristics are able to be improved even in the case of junction-down assembly.

Abstract: A dual wavelength laser device including a cap, a header, a first laser chip and a second laser chip. The cap includes a cap body and a lens embedded on the cap body. The header forms an accommodating space with the cap. The first laser chip is arranged in the accommodating space and emitting a first laser beam toward the lens. The second laser chip is arranged in the accommodating space and emitting a second laser beam toward the lens.

Abstract: An optoelectronic (OE) package or system and method for fabrication is disclosed which includes a silicon layer with a wiring layer. The silicon layer has an optical via for allowing light to pass therethrough. An optical coupling layer is bonded to the silicon layer, and the optical coupling layer includes a plurality of microlenses for focusing and or collimating the light through the optical via. One or more first OE elements are coupled to the silicon layer and electrically communicating with the wiring. At least one of the first OE elements positioned in optical alignment with the optical via for receiving the light. A second OE element embedded within the wiring layer. A carrier may be interposed between electrical interconnect elements and positioned between the wiring layer and a circuit board.

Abstract: A wavelength variable laser includes: a substrate on which an optical coupler is formed as a planar optical waveguide; a DFB array part arranged on the substrate and having DFB laser elements respectively supply optical signals to the optical coupler; and an SOA part arranged on the substrate and having an SOA element configured to amplify an optical signal outputted from the optical coupler. The DFB array part and the SOA part are respectively formed in chips having a same lamination structure to each other. A wavelength variable laser and a modulator integrated wavelength variable laser with high yield ratio can be provided.

Abstract: An extended cavity surface emitting laser has a first laser die with a first cavity and a first gain element and a second laser die with a second cavity and a second gain element. The first and second gain elements are in series to provide optical gain and optical feedback in an extended optical cavity configuration. The first and second gain elements provide optical gain and optical feedback in a common extended cavity with the first and second gain elements operating serially as a common extended cavity optical mode.

Abstract: A semiconductor laser apparatus comprises a first semiconductor laser device that emits a blue-violet laser beam, a second semiconductor laser device that emits a red laser beam, and a conductive package body. The first semiconductor laser device has a p-side pad electrode and an n-side electrode. The p-side pad electrode and n-side electrode of the first semiconductor laser device are electrically isolated from the package body. The p-side pad electrode of the first semiconductor laser device is connected with a drive circuit that generates a positive potential, while the n-side electrode thereof is connected with a dc power supply that generates a negative potential.

Abstract: One embodiment of the present invention provides a system that facilitates adjusting the wavelengths of lasers via temperature control. This system includes a chip with an active face upon which active circuitry and signal pads reside. A thermal-control mechanism provides localized thermal control of two lasers mounted upon the active face of the chip. By individually controlling the temperature of the lasers, the thermal-control mechanism controls the wavelengths emitted by each respective laser. By creating a temperature gradient that causes a temperature difference between two or more lasers, the system can cause the lasers to emit different wavelengths.

Abstract: A semiconductor laser module includes a semiconductor laser section, a light selecting section, and an optical converting section. The semiconductor laser section includes a semiconductor laser substrate, a plurality of semiconductor laser elements mounted on the semiconductor laser substrate, and a first temperature adjusting element for adjusting temperature of the semiconductor laser elements. The light selecting section includes a light selecting element substrate and a light selecting element mounted on the light selecting element substrate and optically connected to the semiconductor laser elements, which selects laser light output from at least one of the semiconductor laser elements.

Abstract: A bar-shaped semiconductor laser chip that can hold down a variation in oscillation wavelength is provided. The bar-shaped semiconductor laser chip has a nitride semiconductor substrate and a semiconductor layer formed on the main surface of the nitride semiconductor substrate and including a plurality of laser chip portions. The plurality of laser chip portions are arrayed in the [11-20] direction. The main surface of the nitride semiconductor substrate is a (0001) plane having an off-angle in the direction along the [11-20] direction. The central part of the main surface of the nitride semiconductor substrate has an off-angle of 0.05±0.1 degrees from the (0001) plane in the direction along the [11-20] direction.

Abstract: An imaging system (200) includes a plurality of laser sources (201) configured to produce a plurality of light beams (204). One or more optical alignment devices (220) orient the light beams (204) into a collimated light beam (205). A light modulator (203) modulates the collimated light beam (205) such that images (206) can be presented on a display surface (207). Speckle is reduced with an optical feedback device (221) that causes the laser sources (201) to operate in a coherence collapsed state. Examples of optical feedback devices (221) include partially reflective mirrors and beam splitter-mirror combinations.

Abstract: A disclosed surface emitting laser device includes a light emitting section having a mesa structure where a lower reflection mirror, an oscillation structure, and an upper reflection mirror are laminated on a substrate, the oscillation structure including an active layer, the upper reflection mirror including a current confined structure where an oxide surrounds a current passage region, a first dielectric film that coats the entire surface of an emitting region of the light emitting section, the transparent dielectric including a part where the refractive index is relatively high and a part where the refractive index is relatively low, and a second dielectric film that coats a peripheral part on the upper surface of the mesa structure. Further, the dielectric film includes a lower dielectric film and an upper dielectric film, and the lower dielectric film is coated with the upper dielectric film.

Abstract: A method of producing a slider wafer populated with electromagnetic components optically aligned with photonic elements for HAMR applications. Laser chips are transferred from a laser substrate wafer to the slider wafer by a massively parallel printing transfer process. After wafer bonding the laser chips to the slider wafer, the shape and optical alignment of the photonic elements are precisely aligned en masse by lithographic processing.

Abstract: The present invention relates to a nitride semiconductor laser device having a structure in which two or more of nitride semiconductor laser elements, having at least a first electrode on a first main surface of a first conductive type conductive substrate, having at least a first conductive type nitride semiconductor layer, an active layer, a second conductive type nitride semiconductor layer, and a second electrode on a second main surface of the conductive substrate, and having a stripe-waveguide structure parallel to the first main surface, are arranged in a direction parallel to the first main surface and a direction perpendicular to the direction of light that is emitted from the stripe waveguide structure in the nitride semiconductor laser device, and the first sub-mount and the first electrode of the nitride semiconductor laser element are electrically and heat-conductively connected, and the second sub-mount and the second electrode of the nitride semiconductor laser element are electrically and heat

Abstract: A substrate having an upper surface and a lower surface is provided. The substrate includes a plurality of v-grooves formed in the upper surface. Each v-groove includes a first side and a second side perpendicular to the first side. A laser diode bar assembly is disposed within each of the v-grooves and attached to the first side. The laser diode bar assembly includes a first adhesion layer disposed on the first side of the v-groove, a metal plate attached to the first adhesion layer, a second adhesion layer disposed over the metal plate, and a laser diode bar attached to the second adhesion layer. The laser diode bar has a coefficient of thermal expansion (CTE) substantially similar to that of the metal plate.

Abstract: Diode lasers type of devices with good coupling between field distribution and gain are disclosed. A single element has a flat field distribution that couples with the uniform current injection in a contact region. A multi element array having almost flat field distribution in each element and almost equal amplitude for the field intensity in all elements is provided. Injection by multiple contacts couples well with the overall field distribution. Also, the lasers are stable against filament formation and mode switching.

Abstract: An imaging device comprising a linear array of laser diodes that are adapted to provide an optical output comprising a plurality of spaced-apart optical beams. Focusing optics are configured to form a plurality of image points from said spaced-apart optical beams, the image points being spaced apart along a first axis. The image points have a non-uniform spacing along the first axis. By scanning the linear array along a photosensitive plate, and timing the firing of lasers accordingly, every pixel point on the photosensitive plate can be imaged by one of the image points from the laser array. Non-uniform spacing of the image points can provide advantages in heat dissipation from the laser elements, and reduction of some printing artifacts on the photosensitive plate.

Abstract: According to an aspect of the invention, there is provided a semiconductor light-emitting element including a substrate, a first stripe, the first stripe including a first n-type clad layer, a first active layer and a first p-type clad layer on the substrate and a second stripe, the second stripe being formed on the substrate and having a different direction for the first stripe direction, the second stripe including a second n-type clad layer, a second active layer and a second p-type clad layer, the second n-type clad layer, the second active layer and the second p-type clad layer substantially being identical with the first n-type clad layer, the first active-layer and the first p-type clad layer, respectively.

Abstract: A vertical cavity surface light emitting device (VCSLED) with multiple active layers includes at least one optical resonance unit comprising a highly-doped conduction region (1), an insulating layer (2), a negative electrode (3), confinement layers (4, 6), an active layer (5), and a positive electrode (7). The optical resonance units are stacked repetitively in a vertical thickness of half wavelength to constitute an optical resonant cavity. In the laser produced from the VCSLED with multiple active layers, the VCSLED is sandwiched by reflectors (104, 105) for emitting and receiving laser light. The laser utilizes the ability of photonic crystal to emit coherent light to improve its electro-optical conversion efficiency and eliminate the fabrication of Bragg reflectors.

Abstract: A semiconductor chip has at least two DFB etched facet laser cavities with one set of facets with AR coatings and a second set of etched facets with HR coatings that have a different relative position with respect to the gratings. This creates a difference in the phase between each of the etched facets and the gratings which changes the operational characteristics of the two laser cavities such that at least one of the lasers provides acceptable performance. As a result, the two cavity arrangement greatly improves the yield of the fabricated chips.

Abstract: A wavelength tunable laser includes a first facet including a high reflection coating film; a gain region disposed adjacent to the first facet, the gain region including two or more light emitting devices that are arranged parallel to one another; an optical wavelength multiplexer optically connected to the light emitting devices; and an optical reflector disposed adjacent to a second facet opposite the first facet, the optical reflector having a reflection spectrum with periodic reflection peaks. The optical wavelength multiplexer is disposed between the gain region and the optical reflector, and the optical reflector and the first facet including the high reflection coating film form a laser cavity.

Abstract: Many approaches to tunable lasers use an array of DFBs, where each element of the array has a different wavelength. In some operations one element of the array is activated at a time depending on the desired wavelength. For modulated applications, an RF voltage is applied to a specific element of the DFB array, generally using an RF switch. In standard configurations, the demands on the switch are relatively difficult, generally requiring low RF insertion loss and good high frequency performance to 10 GHz. The DFB arrays are generally common cathode or common anode, depending on the type of the substrate used to fabricate the devices. Described herein is an array with a common cathode or anode configuration using a MEMS based switch that shorts the selected laser to RF ground. With this topology, preferably the off-state capacitance should be low with the MEMS switch.

Abstract: An imaging system (200) includes a plurality of laser sources (201) configured to produce a plurality of light beams (204). One or more optical alignment devices (220) orient the light beams (204) into a collimated light beam (205). A light modulator (203) modulates the collimated light beam (205) such that images (206) can be presented on a display surface (207). Speckle is reduced with an optical feedback device (221) that causes the laser sources (201) to operate in a coherence collapsed state. Examples of optical feedback devices (221) include partially reflective mirrors and beam splitter-mirror combinations.

Abstract: This semiconductor laser apparatus includes a first semiconductor laser device having a first surface and a second surface, an integrated laser device formed by a second semiconductor laser device and a third semiconductor laser device having a third surface and a fourth surface, and a support substrate. The third surface is bonded onto a first region of the support substrate, a first section of the first surface overlaps with at least part of the fourth surface, and a second section of the first surface is bonded to a second region of the support substrate.

Abstract: A semiconductor surface emitting optical amplifier chip utilizes a zigzag optical path within an optical amplifier chip. The zigzag optical path couples two or more gain elements. Each individual gain element has a circular aperture and includes a gain region and at least one distributed Bragg reflector. In one implementation the optical amplifier chip includes at least two gain elements that are spaced apart and have a fill factor no greater than 0.5. As a result the total optical gain may be increased. The optical amplifier chip may be operated as a superluminescent LED. Alternately, the optical amplifier chip may be used with external optical elements to form an extended cavity laser. Individual gain elements may be operated in a reverse biased mode to support gain-switching or mode-locking.

Abstract: Provided is a surface emitting laser array using a photonic crystal, which allows an active layer to be shared without disconnecting the active layer between the individual surface emitting lasers adjacent to each other, and enables high-density arraying easily. The surface emitting laser array includes: at least two surface emitting lasers formed on a substrate, each having a laminated structure of multiple semiconductor layers including a semiconductor multilayer mirror, an active layer, and a photonic crystal having a refractive index profile in an in-plane direction, the photonic crystal and the semiconductor multilayer mirror in the laminated structure forming a waveguide for guiding light in a resonance mode; and a region without the photonic crystal provided between adjacent surface emitting lasers in the surface emitting laser array, in which the surface emitting lasers have the same semiconductor multilayer mirror and the same active layer.

Abstract: A laser diode package assembly includes a reservoir filled with a fusible metal in close proximity to a laser diode. The fusible metal absorbs heat from the laser diode and undergoes a phase change from solid to liquid during the operation of the laser. The metal absorbs heat during the phase transition. Once the laser diode is turned off, the liquid metal cools off and resolidifies. The reservoir is designed such that that the liquid metal does not leave the reservoir even when in liquid state. The laser diode assembly further includes a lid with one or more fin structures that extend into the reservoir and are in contact with the metal in the reservoir.

Abstract: A surface emitting semiconductor laser includes: a substrate; a first semiconductor multilayer reflector of a first conduction type that is formed on the substrate and is composed of stacked pairs of relatively high refractive index layers and relatively low refractive index layers; a cavity region that is formed on the first semiconductor multilayer reflector and includes an active region; and a second semiconductor multilayer reflector of a second conduction type that is formed on the cavity region and is composed of stacked pairs of relatively high refractive index layers and relatively low refractive index layers. A cavity length of a cavity that includes the cavity region and the active region between the first semiconductor multilayer reflector and the second semiconductor multilayer reflector is greater than an oscillation wavelength.

Abstract: A surface emitting laser element array comprises a plurality of surface emitting laser elements (15) on a same substrate (1) each comprising a mesa post formed of a laminated structure including an active layer (4) for reducing a crosstalk between the surface emitting laser elements constituting the surface emitting laser element array, and for improving a high speed response, wherein each of the surface emitting laser elements (15) comprises a first electrode (9), a second electrode (10) and a third electrode (11) that have a polarity different from that of the first electrode (9); the first electrode (9) is arranged on the mesa post; the second electrode (10) is arranged on one surface of the substrate (1) same as that of the first electrode (9); the third electrode (11) is arranged on the other surface of the substrate (1) opposite to that of the first electrode and the second electrode (9, 10) and is provided as a common electrode of the surface emitting laser elements (15); and an electric current is app

Abstract: An image generating apparatus is provided, which has a plurality of image generating optical paths and means for simultaneously deflecting a received plurality of light beams of primary illumination light having coherence properties. The received light beams are assigned to the respective optical paths. The means for deflecting simultaneously optically couples each of the received light beams into a respective assigned optical path and irradiates intermediate faces of illumination units of each respective optical path with the respective assigned light beam. The means for deflecting is configured so that, during the process of irradiating, each of the light beams subsequently in time irradiates different portions of the respective assigned intermediate faces.

Abstract: A wavelength variable laser smaller in size than the conventional one can be achieved by arranging a gain chip, an etalon filter and a fifth reflective mirror on an AlN submount and longitudinally integrating the gain chip in which a 45° mirror and a lens are integrated and the etalon filter. A laser cavity has a structure in which light passes through an active layer from a first reflective mirror realized by an end surface of the gain chip, is reflected by the 45° mirror at an angle of 90° and then passes through the lens. The light having passed through the lens is converted into parallel light, passes through the etalon filter and reaches the fifth reflective mirror and is then reflected. The reflected light returns through the same optical path and reaches the first reflective mirror realized by the end surface of the gain chip.

Abstract: A laser pump cavity includes a heat sink holder with a central through hole, a plurality of slot portions, and a plurality of single emitters. The single emitter includes a heat sink and a single core disposed on the heat sink. The slot portions are uniformly spaced and surround the through hole. The single emitters are connected end to end, thereby forming at least one single emitter array. The at least one single emitter array is disposed in corresponding slot portions with each single core facing the through hole.

Abstract: A laser cavity is provided by a reflecting spherical substrate with an array of emitters having a mode size. Each emitter has an axis aligned with a radius of the spherical substrate. A single mode waveguide is aligned with the array at an optical coupling distance less than the radius of the spherical substrate. A reflector substantially coincident with an end of the waveguide combines with the reflecting spherical substrate as a cavity.

Abstract: A chaotic light generator device comprises laser structures integrated on a common substrate. Each laser structure comprises a ridge of light amplifying material that forms a waveguide extending between at least partly reflective surfaces. Each laser structure comprises an injection electrode for injecting electric current into the ridge of light amplifying material. The laser structures are mutually coupled for exchanging light. A current feed circuit is coupled to the electrodes and configured to apply mutually different current densities to the electrodes of the laser structures. Choosing different lengths of the laser structures and suitable current densities, chaotic light emission is achieved suitable for telecommunication. Ultrashort pulses result from coupling of Eigenmodes with relaxation oscillations.

Abstract: An object is to provide a wavelength tunable semiconductor laser device, a controller for the same and a control method for the same, which prevent wavelength drifts. The wavelength tunable semiconductor laser device includes an active region for oscillating a laser beam, and a wavelength tuning region for shifting a wavelength of the laser beam. In this device, a thermal compensation region for converting most of the inputted electric power to heat is provided adjacent to the wavelength tuning region, and the sum of an electric power inputted into the wavelength tuning region and an electric power inputted into the thermal compensation region is always kept constant.

Abstract: A power monitoring system uses a low loss reflective element to partially split the output laser beams from an array of laser sources, in a parallel configuration, to produce a monitor beams for each laser source. Each of these monitor beams may propagate within the reflective element in a lossless manner under total internal reflection and into one of a plurality of photodiodes that sense an optical characteristic such as output beam intensity, where this sensed signal is then used as part of a feedback control to control operation of the laser sources in the array.

Abstract: A digital image projector includes a light assembly configured to project light along a light path from at least one laser array light source, the projected light having an overlapping far field illumination in a far field illumination portion of the light path; a temporally varying optical phase shifting device configured to be in the light path; an optical integrator configured to be in the light path; a spatial light modulator located downstream of the temporally varying optical phase shifting device and the optical integrator in the light path, the spatial light modulator configured to be located in the far field illumination portion of the light path; and projection optics located downstream of the spatial light modulator in the light path, the projection optics configured to direct substantially speckle free light from the spatial light modulator toward a display surface.

Abstract: A method of manufacturing a laser diode array capable of inhibiting electric cross talk is provided. The method of manufacturing a laser diode array includes a processing step of forming a peel layer containing an oxidizable material and a vertical resonator structure over a first substrate sequentially from the first substrate side by crystal growth, and then selectively etching the peel layer and the vertical resonator structure to the first substrate, thereby processing into a columnar shape, a peeling step of oxidizing the peel layer from a side face, and then peeling the vertical resonator structure of columnar shape from the first substrate, and a rearrangement step of jointing a plurality of vertical resonator structures of columnar shape obtained by the peeling step to a surface of a metal layer of a second substrate formed with the metal layer on the surface.

Abstract: Provided is a VCSEL array device that includes at least a first multilayer reflective film, an active layer, and a second multilayer reflective film, formed on a substrate that extends in a longitudinal direction. Plural mesa portions are formed on the substrate by selectively removing at least a portion of the first multilayer reflective film, active layer, and second multilayer reflective film. A selectively oxidized region is formed in at least one of the first multilayer reflective film and the second multilayer reflective film. The VCSEL array device further includes an interlayer insulating film that covers at least a side portion and a bottom portion of the mesa portions, and a surface protecting film that covers the interlayer insulating film. The surface protecting film has plural grooves formed along a longitudinal direction of the substrate in which at least a portion of the surface protecting film is removed.

Abstract: An array of optically coupled cavities (called micro-cavities) of a semiconductor laser are defined by either an etch and/or by a native oxide of an aluminum-bearing III-V semiconductor material and are arranged serially end-to-end along the longitudinal direction. An etch and/or native oxide defines a refractive index change for the longitudinal optical mode and confines the optical field within the micro-cavities, resulting in reflection and optical feedback distributed periodically along the laser stripe in the form of an optically coupled micro-cavity. The wavelength of emission of the laser is controlled by a combination of the length of the optical micro-cavities and the spacing between adjacent optical micro-cavities. Single-longitudinal-mode operation is exhibited over an extended drive current range. In one embodiment, two or more linear arrays of end-coupled micro-cavities are arranged in the longitudinal axis of the laser cavity to obtain a tunable laser.

Abstract: High-power, phased-locked, laser arrays as disclosed herein utilize a system of optical elements that may be external to the laser oscillator array. Such an external optical system may achieve mutually coherent operation of all the emitters in a laser array, and coherent combination of the output of all the lasers in the array into a single beam. Such an “external gain harness” system may include: an optical lens/mirror system that mixes the output of all the emitters in the array; a holographic optical element that combines the output of all the lasers in the array, and an output coupler that selects a single path for the combined output and also selects a common operating frequency for all the coupled gain regions.

Abstract: A tunable distributed feedback semiconductor laser includes a substrate; an optical waveguide structure disposed on a main surface of the substrate and including an active layer and a diffraction grating, the optical waveguide structure being divided into a first DFB portion, a wavelength-tuning region, and a second DFB portion in that order; a first electrode for injecting carriers into the active layer in the first DFB portion; a second electrode for injecting carriers into the active layer in the second DFB portion; and a third electrode for supplying a wavelength tuning signal to the wavelength-tuning region. The diffraction grating extends over the first DFB portion, the wavelength-tuning region, and the second DFB portion. An optical confinement factor of the wavelength-tuning region is smaller than that of the first and second DFB portions.

Abstract: An array of optically coupled cavities (called micro-cavities) of a semiconductor laser are defined by either an etch and/or by a native oxide of an aluminum-bearing III-V semiconductor material and are arranged serially end-to-end along the longitudinal direction. An etch and/or native oxide defines a refractive index change for the longitudinal optical mode and confines the optical field within the micro-cavities, resulting in reflection and optical feedback distributed periodically along the laser stripe in the form of an optically coupled micro-cavity. The wavelength of emission of the laser is controlled by a combination of the length of the optical micro-cavities and the spacing between adjacent optical micro-cavities. Single-longitudinal-mode operation is exhibited over an extended drive current range. In one embodiment, two or more linear arrays of end-coupled micro-cavities are arranged in the longitudinal axis of the laser cavity to obtain a tunable laser.

Abstract: Various methods and apparatuses are described in which an array of optical gain mediums capable of lasing are contained in a single integral unit. The array may contain four or more optical gain mediums capable of lasing. Each optical gain medium capable of lasing supplies a separate optical signal containing a band of wavelengths different than the other optical gain mediums capable of lasing in the array to a first multiplexer/demultiplexer. A connection for an output fiber exists to route an optical signal to and from a passive optical network.