Abstract: A light emitting device includes a stacked body including at least a light emitting layer made of Inx(AlyGa1-y)1-xP (0?x?1, 0?y?1), a p-type cladding layer made of Inx(AlyGa1-y)1-xP (0?x?1, 0?y?1), and a bonding layer made of a semiconductor; and a substrate in which deviation in a lattice constant at a bonding interface with the bonding layer is larger than deviation in lattice constants between the light emitting layer and the bonding layer. The p-type cladding layer is located more distant from the bonding interface than the light emitting layer, and the p-type cladding layer has a carrier concentration of 0.5×1017 cm?3 or more and 3×1017 cm?3 or less.

Abstract: Current may be passed through an n-doped semiconductor region, a recessed metal semiconductor alloy portion, and a p-doped semiconductor region so that the diffusion of majority charge carriers in the doped semiconductor regions transfers heat from or into the semiconductor waveguide through Peltier-Seebeck effect. Further, a temperature control device may be configured to include a metal semiconductor alloy region located in proximity to an optoelectronic device, a first semiconductor region having a p-type doping, and a second semiconductor region having an n-type doping. The temperature of the optoelectronic device may thus be controlled to stabilize the performance of the optoelectronic device.

Abstract: A surface emitting photonic device including a substrate; and a waveguide structure on the substrate. The waveguide structure includes an active region along its longitudinal axis and the active region is for generating light. The waveguide structure also has a trench formed therein transverse to the active region and defining a first wall forming an angled facet at one end of the active region, the first wall having a normal that is at a non-parallel angle relative to the longitudinal axis of the waveguide structure. The trench also defines a second wall located opposite the first wall.

Abstract: A mode selection technique in a laser is described wherein a recess is formed in a surface of a waveguide in the laser. The recess provides a region of free space propagation within the waveguide which preferentially selects the lowest order mode. A mode selective RF excited CO2 slab laser, having a stable resonator in the waveguide dimension and a negative branch unstable resonator in the non-waveguide dimension, is constructed and the position and size of the recess is considered to provide low order mode selection.

Abstract: A laser-induced optical wiring apparatus includes a substrate, first and second light-reflecting members provided on the substrate separately from each other, an optical waveguide provided on the substrate for optically coupling the first and second light-reflecting members to form an optical resonator, a first optical gain member provided across the optical waveguide and forming a laser oscillator along with the first and second light-reflecting members, and a second optical gain member provided across the optical waveguide separately from the first optical gain member, and forming another laser oscillator along with the first and second light-reflecting members.

Abstract: Provided is a resonator of a hybrid laser diode. The resonator includes: a substrate including a semiconductor layer where a hybrid waveguide, a multi-mode waveguide, and a single mode waveguide are connected in series; a compound semiconductor waveguide, provided on the hybrid waveguide of the semiconductor layer, having a tapered coupling structure at one end of the compound semiconductor waveguide, the tapered coupling structure overlapping the multi-mode waveguide partially; and a reflection part provided on one end of the single mode waveguide. The multi-mode waveguide has a narrower width than the hybrid waveguide and the single mode waveguide has a narrower width than the multi-mode waveguide.

Abstract: An RF excited gas discharge laser is disclosed including a housing holding the lasing gas. An electrode assembly is mounted within the housing. The electrode assembly includes a pair of elongated planar electrodes mounted in face to face relationship with a narrow gap therebetween. A pair of planar dielectric plates are positioned along the side edges of the gap to seal the discharge region. The plates extend part of the way into the gap from both sides edges of the electrodes. The inner surfaces of the electrodes are provided with an opposed trench in the region surrounding the inner edges of the plates. In this way, the exposure of the inner edges of the plates to the discharge is minimized improving performance.

Abstract: In one aspect, the disclosure features an article, including a fiber waveguide extending along a waveguide axis, the fiber waveguide including a core extending along the waveguide axis and a confinement region surrounding the core. The confinement region is configured to guide radiation at a first wavelength, ?1, along the waveguide axis and is configured to transmit at least some of the radiation at a second wavelength, ?2, incident on the confinement region along a path, where ?1 and ?2 are different. The core includes a core material selected to interact with radiation at ?1 to produce radiation at ?2.

Abstract: Narrow surface corrugated gratings for integrated optical components and their method of manufacture. An embodiment includes a grating having a width narrower than a width of the waveguide on which the grating is formed. In accordance with certain embodiments of the present invention, masked photolithography is employed to form narrowed gratings having a desired grating strength. In an embodiment, an optical cavity of a laser is formed with a reflector grating having a width narrower than a width of the waveguide. In another embodiment an integrated optical communication system includes one or more narrow surface corrugated gratings.

Abstract: A light coupler emitting a high power laser with a high beam quality and a fiber laser system including the light coupler is disclosed. The light coupler includes a first optical fiber bundle comprising a plurality of first optical fibers having either a single-mode core or a few-mode core and a second optical fiber, which guides multi-mode beams and is connected to the first optical fiber bundle. The optical fiber laser system includes a light coupler having a first optical fiber bundle comprising a plurality of first optical fiber having either a single-mode core or a few-mode core and a second optical fiber, which is connected to the first optical fiber bundle, is either a single cladding optical fiber or a double cladding optical fiber, and guides multi-mode beams, and one or more gain medium optical fiber, which is connected to the light coupler and emits light.

Abstract: A laser-induced optical wiring apparatus includes a substrate, first and second light-reflecting members provided on the substrate separately from each other, an optical waveguide provided on the substrate for optically coupling the first and second light-reflecting members to form an optical resonator, a first optical gain member provided across the optical waveguide and forming a laser oscillator along with the first and second light-reflecting members, and a second optical gain member provided across the optical waveguide separately from the first optical gain member, and forming another laser oscillator along with the first and second light-reflecting members.

Abstract: An optical arrangement comprising first and second guided structures for providing first and second beams of electromagnetic energy and a node for coherently combining said first and second beams in free space, that is, with an unguided structure. In the illustrative embodiment, the first and second structures are first and second fiber oscillators. The first and second fiber oscillators may be of unequal lengths. The node may be implemented with a polarizing beam splitter or a semi-reflective surface. Beam shaping optics are included in the node to collimate the first and second beams and provide a flat profile mode thereof. The outputs of plural first and second fiber oscillators are combined via plural nodes to provide a single high energy output beam. Amplifying elements may be disposed between nodes. The plural nodes may be disposed in a single integrated structure along with an outcoupler mirror to coherently phase lock the outputs of the plural oscillators.

Abstract: RF power is transmitted to a CO2 gas discharge laser form a source of RF power via a series combination of transmission line sections. The lengths and characteristic impedances of the transmission line sections are selected to transform the impedance of the RF power source to the operating impedance of the laser.

Abstract: A single-mode, etched facet distributed Bragg reflector laser includes an AlGaInAs/InP laser cavity, a front mirror stack with multiple Fabry-Perot elements, a rear DBR reflector, and a rear detector. The front mirror stack elements and the rear reflector elements include input and output etched facets, and the laser cavity is an etched ridge cavity, all formed from an epitaxial wafer by a two-step lithography and CAIBE process.

Abstract: In an edge emitting semiconductor laser comprising an active layer (3) that generates laser radiation (13) and is embedded into a first waveguide layer (1), wherein the first waveguide layer (1) is arranged between a first cladding layer (4) and a second cladding layer (5) and is delimited by side facets (9) of the semiconductor laser in a lateral direction, a second waveguide layer (2), into which no active layer is embedded, adjoins the second cladding layer (5), the second waveguide layer (2) being optically coupled to the first waveguide layer (1) at least in partial regions (10, 11), and a third cladding layer (6) is arranged at a side of the second waveguide layer (2) that is remote from the first waveguide layer (1).

Abstract: A separate-confinement heterostructure, edge-emitting semiconductor laser having a wide emitter width has elongated spaced apart intermixed and disordered zones extending through and alongside the emitter parallel to the emission direction of the emitter. The intermixed zones inhibit lasing of high order modes. This limits the slow axis divergence of a beam emitted by the laser.

Abstract: An RF excited laser assembly includes a pair of opposed electrodes, and at least one inductor. The pair of opposed electrodes defines an inter-electrode gap that provides a discharge volume for laser propagation within a gas medium. The pair of opposed electrodes define one or more discharge-free regions within a laser-free region in the inter-electrode gap. The least one inductor is electrically connected to both electrodes and extends between the electrodes within the inter-electrode gap and inside of the one or more discharge-free regions within the laser-free region.

Abstract: A laser-induced optical wiring apparatus includes a substrate, first and second light-reflecting members provided on the substrate separately from each other, an optical waveguide provided on the substrate for optically coupling the first and second light-reflecting members to form an optical resonator, a first optical gain member provided across the optical waveguide and forming a laser oscillator along with the first and second light-reflecting members, and a second optical gain member provided across the optical waveguide separately from the first optical gain member, and forming another laser oscillator along with the first and second light-reflecting members.

Abstract: The present invention provides a system, which comprises a fiber laser (1) for generation of laser radiation, and an applicator (8) coupled with the fiber laser (1), the applicator (8) being adapted for delivery of laser radiation from the fiber laser (1) to an area of interest (22) and comprising an endoscopic fiber (7) or bare fiber (7).

Abstract: An excimer laser cavity is disclosed which includes at least one grating-prism (grism) and a wavelength-selective diffraction grating arranged in sequence. The grism grating surface faces the gain medium and produces an expanded beam which is diffracted on the same side of the prism grating surface normal as the incident beam. The expanded diffracted beam is transmitted through a second surface of the grism either to another grating surface of an additional grism or to a wavelength-selective diffraction grating operating in Littrow configuration. The laser produces a laser output beam with a narrow spectral linewidth which is suitable, in particular, for lithography applications.

Abstract: It is made possible to provide an optical waveguide system that has a coupling mechanism capable of selecting a wavelength and has the highest possible conversion efficiency, and that is capable of providing directivity in the light propagation direction. An optical waveguide system includes: a three-dimensional photonic crystalline structure including crystal pillars and having a hollow structure inside thereof; an optical waveguide in which a plurality of metal nanoparticles are dispersed in a dielectric material, the optical waveguide having an end portion inserted between the crystal pillars of the three-dimensional photonic crystalline structure, and containing semiconductor quantum dots that are located adjacent to the metal nanoparticles and emit near-field light when receiving excitation light, the metal nanoparticles exciting surface plasmon when receiving the near-field light; and an excitation light source that emits the excitation light for exciting the semiconductor quantum dots.

Abstract: A semiconductor laser device includes an active layer, a pair of guiding layers sandwiching the active layer, and a pair of cladding layers sandwiching the active layer and the pair of guiding layers. The pair of guiding layers are InGaAsP lattice-matched to GaAs. The pair of cladding layers are AlGaAs. The Al composition ratios of the pair of AlGaAs cladding layers are 0.4 or less. The Al composition ratios are set such that the refractive indices of the pair of AlGaAs cladding layers do not exceed those of the pair of InGaAsP guiding layers.

Abstract: A mode selection technique in a laser is described wherein a recess is formed in a surface of a waveguide in the laser. The recess provides a region of free space propagation within the waveguide which preferentially selects the lowest order mode. A mode selective RF excited CO2 slab laser, having a stable resonator in the waveguide dimension and a negative branch unstable resonator in the non-waveguide dimension, is constructed and the position and size of the recess is considered to provide low order mode selection.

Abstract: An apparatus is provided that includes a laser that produces light at a first wavelength, an optical element that converts the light at the first wavelength received at an input end thereof into light at a second wavelength, and an optical interface proximate the input end of the optical element that directs light at the second wavelength through the optical element toward an output end of the optical element.

Abstract: A cladding is provided at an outer periphery of a solid-core doped with rare earth ions, and a metal layer is formed to be adjacent to the cladding to provide an optical fiber for a fiber laser device. The metal layer having an inner metal layer and an outer metal layer is disposed along an entire length of the optical fiber for a fiber laser device. An exciting light is incident to the optical fiber for a fiber laser device, and the exciting light is reflection-excited to emit a high power laser oscillation light. A monitoring current is constantly flown into the metal layer. When the disconnection of the optical fiber for a fiber laser device is detected based on the monitoring current, the energization of the optical fiber for a fiber laser device is stopped.

Abstract: An optical semiconductor device includes an optical semiconductor element, a metal pattern and at least one thermal conductive material. The optical semiconductor element has a first optical waveguide region and a second optical waveguide region. The second optical waveguide region is optically coupled to the first optical waveguide region and has a heater for changing a refractive index of the second optical waveguide region. The metal pattern is provided on an area to be thermally coupled to a temperature control device. The thermal conductive material couples the metal pattern with an upper face of the first optical waveguide region of the optical semiconductor element. The thermal conductive material is electrically separated from the first optical waveguide region.

Abstract: A laser chamber is provided that increases power, initiation, and discharge efficiency over single chamber lasers by providing a multi-fold laser chamber, protrusions, discharge segmentation and inversion techniques.

Abstract: An optical continuum source is formed that is used to generate both a continuum and one or more light peaks outside the bandwidth of the continuum. In particular, one or more fiber Bragg gratings exhibiting a resonant wavelength less than the short wavelength edge (or greater than the long wavelength edge) of a predetermined continuum are inscribed into a section of highly nonlinear fiber (HNLF) and used to generate the additional light peaks. Gratings may also be formed for areas along the fiber where the continuum spectral power density is essentially “zero”. It has been discovered that the use of a Bragg grating generates phase matching with the propagating optical signal, thus resulting in the creation of the additional peaks.

Abstract: A phase plate and lens modify light beams emitted by an array of lasers to form an efficient illumination source for a MEMS light modulator array. The phase of the electric field emitted by the lasers is modified such that the after passing through a lens the beam profile at the lens focal plane has an approximately rectangular shape appropriate for illuminating a light modulator array. The phase plate may be constructed from a glass plate with rectangular notches etched in it or with rectangular ridges formed on it. Furthermore a light source, such as a laser, may be coupled to an adiabatically tapered optical waveguide in which a phase adjusting block is introduced in analogy to notches in a bulk phase plate. Phase modified light beams output from the waveguide system have similar focusing properties to those passing through a bulk phase plate.

Abstract: A near-field light emitting device includes a deflecting unit that deflects electromagnetic waves propagated through a core toward a base. A propagating unit arranged on the base emits near-field light from an outlet. By providing a magnetic head on a side opposite to the base, a distance between the magnetic head and an intensity center of the near-field light can be minimized. The deflecting unit is formed comparatively thick, therefore, the electromagnetic wave is caused to enter the propagating unit at such an angle that causes a surface-propagating wave to be generated highly efficiently.

Abstract: Photodarkening in active fiber or waveguide devices (e.g. lasers, amplifiers, and incoherent sources such as ASE sources) can be reduced by altering the dopant concentration along the length of the doped fiber. A fiber or waveguide device includes two or more intentionally doped fiber or waveguide sections having different concentrations of one or more dopants. The dopants provide optical gain responsive to pump radiation provided to the fiber device by a pump source. A first optical intensity in a first of the fiber or waveguide sections is greater than a second optical intensity in a second of the fiber or waveguide sections. A first dopant concentration in the first fiber or waveguide section is lower than a second dopant concentration in the second fiber or waveguide section. Thus the dopant concentration is reduced in sections of the fiber or waveguide device having a higher optical intensity. The optical intensity can be due to pump radiation and/or signal radiation.

Abstract: An optical semiconductor device includes an optical semiconductor element, a metal pattern and at least one thermal conductive material. The optical semiconductor element has a first optical waveguide region and a second optical waveguide region. The second optical waveguide region is optically coupled to the first optical waveguide region and has a heater for changing a refractive index of the second optical waveguide region. The metal pattern is provided on an area to be thermally coupled to a temperature control device. The thermal conductive material couples the metal pattern with an upper face of the first optical waveguide region of the optical semiconductor element. The thermal conductive material is electrically separated from the first optical waveguide region.

Abstract: To provide a semiconductor laser diode and a semiconductor optical amplifier and an optical communication device incorporating the semiconductor laser diode or the semiconductor optical amplifier which enable low power consumption and high optical output. A semiconductor laser diode according to an embodiment of the present invention is a semiconductor laser diode 100 comprised of an active waveguide, the active waveguide including a first waveguide 11a that supplies a plurality of modes including a fundamental mode; and a second waveguide 12a that is wider than the first waveguide 11a and supplies a multimode, wherein the fundamental mode is provided as an oscillation light oscillated from the active waveguide.

Abstract: An RF excited gas laser including an offset V-shaped laser cavity. The laser includes a first and second ceramic body portions with the laser cavity at least partially defined by the ceramic body portions. At least one internal gas reservoir is also at least partially defined by the first and second body portions, with the internal gas reservoir being in gas communication with laser cavity by way of at least one gas communication slot. The RF laser further includes at least two electrode slots formed in the exterior of the ceramic body portions and an electrode at least partially received in the electrode slots.

Abstract: Laser diodes are formed with an outcoupling grating between two separate distributed Bragg reflectors. The devices have gain regions located between the reflector gratings for pumping the active region. The outcoupling grating couples light out of the waveguide normal to the surface if the grating spacings are equal to an integer number of wavelengths of the light within the cavity. If the gratings are not such an integer number, the light is coupled out of the cavity off the normal.

Abstract: A lighting system includes a microwave resonator (2) for generating a standing microwave in the internal space, and a gas cell (6) enclosing a medium is disposed in the internal space of the microwave resonator 2. The lighting system excites the medium in the gas cell (6) by the standing microwave to generate light. The gas cell (6) is replaceably mounted on the microwave resonator (2). The generated light is output to the outside of the microwave resonator (2) through a light lead-out hole (26). Thereby, it is possible to provide a lighting system (including a gas laser) capable of emitting light efficiently with a compact and inexpensive device configuration and of achieving a long life. Moreover, it can also be used as a lighting system in the THz-wave region by enclosing the medium for generating light in the far-infrared region in the gas cell (6).

Abstract: A laser-induced optical wiring apparatus includes a substrate, first and second light-reflecting members provided on the substrate separately from each other, an optical waveguide provided on the substrate for optically coupling the first and second light-reflecting members to form an optical resonator, a first optical gain member provided across the optical waveguide and forming a laser oscillator along with the first and second light-reflecting members, and a second optical gain member provided across the optical waveguide separately from the first optical gain member, and forming another laser oscillator along with the first and second light-reflecting members.

Abstract: A device contains at least one leaky waveguide layer, and has a transparent substrate, having a higher refractive index. The leakage loss of the waveguide exceeds the modal gain needed to initiate waveguide lasing. The leaky emission is going into the substrate at a certain angle, is reflected from the substrate back surface, and returns towards the leaky waveguide layer exhibiting constructive or destructive interference. As the leakage emission is returned to the active medium, the low threshold current density lasing is possible. As the leakage angle is defined for a given wavelength, interference enables lasing only at certain wavelengths making it possible to realize wavelength-selectivity. The lobes of the output emission can be made arbitrarily narrow by increasing the thickness of the substrate and the exit angle of the lobes is controlled by the leakage angle of the waveguide.

Abstract: The present invention provides semiconductor lasers having an Active-Photonic-Crystal (APC) structure that allows scaling of the coherent power by using a waveguide having a periodic structure that selects operation in a single spatial mode from large-aperture devices. The lasers include an active medium that includes an array of quantum box ministacks, each ministack containing 2 to 5 vertically stacked, coupled quantum boxes.

Abstract: A semiconductor laser comprises two optical cavities, each comprising an optical waveguide bounded by two partially reflecting elements. The two optical waveguides are disposed on a substrate to form a substantially V-shaped geometry with substantially no cross-coupling at the open end and a predetermined cross-coupling at the closed end for achieving an optimal single-mode selectivity of the laser. The first cavity has a length such that its resonant wavelengths correspond to a set of discrete operating channels. The second cavity has a slightly different length so that only one resonant wavelength coincides with one of the resonant wavelengths of the first cavity over the operating spectral window. The lasing action occurs at the common resonant wavelength. In operation, at least a portion of the optical waveguide in each of the first and the second cavities are forward biased to provide substantially equal round-trip optical gains.

Abstract: A semiconductor laser diode that internally converts one or more short wavelength “pump” beams to an output beam at a longer wavelength using nonlinear optical frequency conversion in the semiconductor. Modal phase matching of the pump and output beams in a semiconductor waveguide allows the conversion process to proceed with high efficiency.

Abstract: After forming domain inverted layers 3 in an LiTaO3 substrate 1, an optical waveguide is formed. By performing low-temperature annealing for the optical wavelength conversion element thus formed, a stable proton exchange layer 8 is formed, where an increase in refractive index generated during high-temperature annealing is lowered, thereby providing a stable optical wavelength conversion element. Thus, the phase-matched wavelength becomes constant, and variation in harmonic wave output is eliminated. Consequently, with respect to an optical wavelength conversion element utilizing a non-linear optical effect, a highly reliable element is provided.

Abstract: A PLC-based wavelength-tunable WDM-PON system with an optical wavelength alignment function, the WDM-PON system comprises: a PLC platform formed on a silicon substrate; a semiconductor chip comprising an active region generating light and a passive region located in front of the active region for vertically coupling the light generated in the active region; a planar lightwave circuit (PLC) waveguide; one portion of a PLC platform where the semiconductor chip is surface mounted; waveguide Bragg grating (WBG) formed at a predetermined location of the PLC waveguide; a directional coupler transferring an optical power by permitting the passive region to approach the PLC waveguide; a heater terminal, which is formed on the WBG; and a V-groove for attaching an optical fiber to another end of the PLC waveguide. Accordingly, a WDM-PON system having a function of realizing a cost-effective optical wavelength alignment can be provided.

Abstract: A narrow linewidth fluorescent emitter can incorporate a chromophore into a microcavity that can support low-order optical modes.

Abstract: The present invention is related to a method and device for precision and passive alignment such as precision and passive alignment technology for low cost array fibre access components. A laser carrier is passively aligned to an MT-interface using alignment structures on a replicated carrier. The laser carrier is based on a self-aligned semiconductor laser, flip-chip mounted on a silicon substrate with planar polymeric waveguides.

Abstract: A method and apparatus for optimizing the numerical aperture (NA) of a laser active core. The laser active core comprises at least a first and second cladding pair. The first and second cladding pair have at least one NA value. At least one of the first and second cladding pair is doped with a dopant to change the first NA value to a second NA value.

Abstract: A slab laser includes two elongated electrodes arranged spaced apart and face-to-face. Either one or two slabs of a solid dielectric material extend along the length of the electrodes between the electrodes. A discharge gap is formed either between one of the electrodes and one dielectric slab, or between two dielectric slabs. The discharge gap is filled with lasing gas. A pair of mirrors is configured and arranged to define a laser resonator extending through the gap. An RF potential is applied across the electrodes creating a gas discharge in the gap, and causing laser radiation to circulate in the resonator. Inserting dielectric material between the electrodes increases the resistance-capacitance (RC) time constant of the discharge structure compared with the RC time constant in the absence of dielectric material.

Abstract: A semiconductor laser device comprises an n-type cladding layer 103 made of n?type (Al0.3Ga0.7)0.5In0.5P, an undoped active layer 104 and a first p-type cladding layer 105 made of p?type (Al0.3Ga0.7)0.5In0.5P. These layers are successively stacked in bottom-to-top order. The active layer 104 has a multi-quantum well structure composed of a first optical guide layer of undoped Al0.4Ga0.6As, a layered structure in which well layers of undoped GaAs and barrier layers of undoped Al0.4Ga0.6As are alternately formed, and a second optical guide layer of undoped Al0.4Ga0.6As. The first optical guide layer, the layered structure and the second optical guide layer are successively stacked in bottom-to-top order.

Abstract: A laser beam generating unit has a semiconductor laser unit having a plurality of beam emitting portions located in the shape of a matrix, and a plurality of optical fibers for individually transmitting laser beam emitted from the beam emitting portions. An optical fiber bundle is formed by binding a plurality of the optical fibers on a side where laser beam emits, and laser beam is emitted through a taper adaptor provided on the side where laser beam emits. Then, laser beam can be transmitted by the optical fibers at a good condition, and can be collected by a beam transmitting path of the adaptor having the thinner diameter with high efficiency and the power density can be raised.

Abstract: Continuously tunable and precisely wavelength-switchable fiber lasers combine fiber Bragg gratings and the transmissive filtering properties of high finesse fiber Fabry-Perot filters. This laser arrangement adapts to multiple wavelength ranges based on the selections of fiber Bragg grating and gain medium and their arrangement to create a wavelength-modulatable and simultaneously rapidly wavelength-switchable narrow linewidth all-fiber laser design. This laser arrangement further results in narrow-linewidth outputs with fast switching speeds between the selected wavelengths.