Abstract: A free electron laser system includes an undulator having a first and second series of magnets. The first and second series of magnets are substantially parallel to and spaced apart from each other to define a laser cavity between the magnets. An electron source emits an electron beam through the laser cavity. The magnets in the first and second series can have varying polarities. The magnets can be electromagnets with random phase distribution.

Abstract: A swept wavelength light source is provided, the light source includes a semiconductor gain device operable to provide amplification, an optical retarding device, the retarding device having a block of material, a beam path with a well-defined beam path length being defined for light within the block of material produced by the gain device, a wavelength selector, and the gain device, the retarding device and wavelength selector being mutually arranged on the base so that a resonator is established for light portions emitted by the gain device and selected by wavelength selector; this does not exclude the presence of further elements contributing to the resonator, such as additional mirrors (including resonator end mirrors), lenses, polarization selective elements, other passive optical components, etc.; wherein the beam path in the retarding device is a part of a beam path of the resonator.

Abstract: A photonic crystal surface emission laser includes an active layer, and a photonic crystal layer made of a plate-shaped slab provided with modified refractive index area having a refractive index different from that of the slab, the modified refractive index areas being arranged on each of the lattice points of a first rhombic-like lattice and a second rhombic-like lattice in which both diagonals are mutually parallel and only one diagonal is of a different length, wherein ax1, ax2, ay, and n satisfy the following inequality: ? 1 a x ? ? 1 - 1 a x ? ? 2 ? ( 1 a x ? ? 1 + 1 a x ? ? 2 ) 2 + ( 2 a y ) 2 ? 1 n .

Abstract: In one embodiment, a semiconductor laser includes a semiconductor laminated body formed in a ring shape and first and second electrodes. The semiconductor laminated body includes an active layer, first and second cladding layers formed on both sides of the active layer, first and second contact layers formed on the first and second cladding layers, and first and second modified layers. The first and second modified layers are formed by selectively modifying the inner peripheral sidewalls and the outer peripheral sidewalls of the first and second cladding layers so as to have a refractive index lower than the refractive indexes of the first and second cladding layers. The first and second contact layers are electrically connected to the first and second electrodes.

Abstract: Long semiconductor laser cavities are placed in relative short length chips through the use of total internal reflection (TIR) surfaces formed through etched facets. In one embodiment, a laser cavity is formed along the perimeter edges of a rectangular semiconductor chip by using three 45° angled TIR facets to connect four legs of a ridge or buried heterostructure (BH) waveguide that defines the laser cavity. In other embodiments, even more TIR facets and waveguide legs or sections are employed to make even longer laser cavities in the shape of rectangular or quadrilateral spirals. These structures are limited in the spacing of adjacent waveguide sections, which if too small, can cause undesirable coupling between the sections. However, use of notches etched between the adjacent sections have been shown to decrease this coupling effect.

Abstract: A high power source of electro-magnetic radiation having a multi-purpose housing is disclosed. The multi-purpose housing includes an interior filled with a material forming at least a light source and further comprising a reflector which can envelope a laser rod surrounded by light sources for providing light excitation to the laser rod. A material defining outer surfaces of the light sources extends out to and defines outer surfaces of the reflector. A high-reflectivity coating is disposed over an outer surface of the reflector, as is a protective coating. Also disposed over an outer surface of the reflector can be an optional heat sink, with cooling being performed by an optional arrangement of forced-air traveling over the heat sink. The light sources may be light source pumps, and the high-reflectivity coating may be formed to envelop the reflector.

Abstract: A radiation source that provides high order harmonic radiation (HHG radiation) in an UV or XUV wavelength range comprising a resonant cavity that guides laser light pulses that includes at least two cavity mirrors, a first non-linear medium that provides the HHG radiation by harmonic generation based on an interaction of the laser light pulses with the first non-linear medium, wherein the first non-linear medium is arranged in the resonant cavity in an environment of reduced pressure, and a second non-linear medium arranged in the resonant cavity and adapted for at least one of amplifying the laser light pulses and phase locking longitudinal modes of the laser light pulses in the resonant cavity.

Abstract: A laser light source having a semiconductor laser light source which emits a laser beam, a laser medium excited by the semiconductor laser light source to emit light, two reflectors configured to work as a resonator to confine the light emitted by the laser medium, and a holder which holds the laser medium, wherein stress is generated in the laser medium formed of a ceramic material situated in the resonator so as to control a polarization direction of the light emitted by the laser medium.

Abstract: A light emitting device includes first and second cladding layers and an active layer therebetween including first and second side surfaces and first and second gain regions, a second side reflectance is higher than a first side reflectance, a first end surface part of the first gain region overlaps a second end surface part of the second gain region in an overlapping plane, the first gain region obliquely extends from the first end surface to a third end surface, the second gain region obliquely extends from the second end surface to a fourth end surface, a first center line connecting the centers of the first and third end surfaces and a second center line connecting the centers of the second and fourth end surfaces intersect, and the overlapping plane is shifted from the intersection point toward the first side surface.

Abstract: A laser light source (100) according to the present invention includes a laser resonator (150) including a fiber (107) containing a laser active medium and a fiber grating (105, 160) coupled to each of two ends of the fiber (107); an pumping laser light source (104) for emitting pump light into the laser resonator (150); a driving current supply circuit (102) for supplying a pulse-like driving current to the pumping laser light source (104); and a wavelength conversion element (101) for converting a wavelength of laser light which is output from the laser resonator. The laser resonator (150) generates laser light including a principal pulse and a plurality of superimposing pulses which are superimposed on the principal pulse, in accordance with incidence of the pump light; and converted light having the wavelength of each of the principal pulse and the superimposing pulses shortened is generated by the wavelength conversion element (101).

Abstract: A method includes: positioning a laser in the cavity in an end of a slider, wherein the laser has an output facet positioned adjacent to a first wall of the cavity to define a first gap between the output facet and the first wall of the cavity, and filling at least a portion of the first gap adjacent to the output facet. An apparatus including a slider including a cavity in a trailing end of the slider, a laser positioned in the cavity and having an output facet positioned adjacent to a first wall of the cavity to define a first gap between the output facet and the first wall of the cavity, and a sealing material filling at least a portion of the first gap adjacent to the output facet is also provided.

Abstract: An external-cavity one-dimensional multi-wavelength beam combiner that performs wavelength beam combining along a stacking dimension of a laser stack formed of a plurality of laser arrays, each laser array configured to generate optical radiation having a unique wavelength, and each of the plurality of laser arrays including one or more laser emitters arranged along an array dimension of the laser stack. The multi-wavelength beam combiner includes an optical imaging element configured to image each of the laser emitters along a slow axis of the laser emitters, an optical focusing element arranged to intercept the optical radiation from each of the plurality of laser arrays and combine the optical radiation along a stacking dimension of the laser stack to form a multi-wavelength optical beam, and a diffraction element positioned at a region of overlap of the optical radiation to receive and transmit the multi-wavelength optical beam.

Abstract: A compact laser in accordance with an exemplary embodiment in the present disclosure includes a compact resonator structure using a non-planar resonator geometry of bulk components. The laser further includes a laser gain medium and a pump source integrated within an optical path of the resonator. Some embodiments contain modifications to the resonator structure for integration of the laser gain medium, for controlling the output from the laser, and/or for controlling the physical and operational parameters of the laser. Some embodiments contain modifications to the laser gain medium or other bulk components of the resonator to integrate these bulk components within the resonator structure.

Abstract: The present invention relates to a solid dye resonator, and to a solid dye laser hand piece comprising same. The solid dye resonator comprises: solid dye; a high-reflection mirror; an output coupler; a first mounting plate on which the high-reflection mirror is mounted; a second mounting plate which is spaced apart from the first mounting plate and which has a surface on which the output coupler is mounted; a driving motor mounted on the first mounting plate, such that a motor shaft is directed toward the second mounting plate; and a rotary shaft interposed between the first mounting plate and the second mounting plate, and connected to the motor shaft of the driving motor such that the rotary shaft interlockingly rotates with the rotation of the driving motor.

Abstract: A composite optical waveguide 1 includes a first optical waveguide 9 comprising a silica-based core and a second optical waveguide 11 comprising an Si-based core. The second optical waveguide 11 is joined to the first optical waveguide 9. The length of the first optical waveguide 9 corresponds to a permissible propagation loss of the second optical waveguide 11. The second optical waveguide 11 includes a sharply curved portion 13 having a radius smaller than the minimum bend radius of the first optical waveguide 9.

Abstract: A compact solid state laser that generates multiple wavelengths and multiple beams that are parallel, i.e., bore-sighted relative to each other, is disclosed. Each of the multiple laser beams can be at a different wavelength, pulse energy, pulse length, repetition rate and average power. Each of the laser beams can be turned on or off independently. The laser is comprised of an optically segmented gain section, common laser resonator with common surface segmented cavity mirrors, optically segmented pump laser, and different intra-cavity elements in each laser segment.

Abstract: A method for introducing light into a waveguide formed on the upper surface of a microelectronics substrate, by means of a distributed feedback laser device formed by the association of an SOI-type structure having a portion forming said waveguide, of a stack of III-V semiconductor gain materials partially covering the waveguide, and of an optical grating, wherein the grating step is selected so that the optical power of the laser beam circulates in a loop from the III-V stack to the waveguide.

Abstract: A light-emitting device having a ring optical resonator and capable of laser oscillation by a novel structure realized by working out the mechanism of light emission. The light-emitting device having a ring optical resonator fabricated on a base is characterized in that the optical resonator has a core made of a semiconductor and serving to propagate light and a clad formed on at least the base side of the core in the stack direction out of the base side and the opposite side of the core, at least the ring inner and outer peripheral surfaces of the core are covered with a transparent body having an index of refraction lower than that of the space or the clad, and a part of the ring inner and outer peripheral surfaces of the clad are covered with a transparent body having an index of refraction lower than that of the space or the clad.

Abstract: An external cavity laser assembly (10) that generates a light beam (12) includes a gain medium (14) and a diffraction grating (24). The gain medium (14) has a growth direction (14C), a fast axis (14A), a first facet (34A), and a second facet (34B) that is spaced apart from the first facet (34A). The gain medium (14) emits from both facets (34A) (34B). Further, a beam polarization (30) of the light beam (32) emitting from the second facet (34B) is perpendicular to the growth direction (14C) and the fast axis (14A). The grating (24) includes a plurality of grating ridges (24A) that are oriented parallel to the beam polarization (30). Moreover, each of the grating ridges (24A) can have a substantially rectangular shaped cross-sectional profile.

Abstract: The multi-channel optical device includes multiple laser cavities that each reflects a different light channel back and forth between reflective components. One of the reflective components is common to all of the laser cavities in that the common reflective component receives the channels from each of the laser cavities and reflects the received channels. The laser cavities also share a multiplexer that receives the channels reflected by the common reflective device and demultiplexes the channels into demultiplexed channels. A portion of the reflective components are partial return devices that each receives one of the demultiplexed channels. Each of the partial return devices transmits a portion of the demultiplexed channel received by that partial return device. The transmitted portion of the demultiplexed channel exits the laser cavity. Additionally, each of the partial return devices reflects a portion of the demultiplexed channel receive by that partial return device.

Abstract: According to one embodiment, the present application includes a tunable laser configured in a small package. The tunable laser includes a housing with a volume formed by exterior walls. An electrical input interface is positioned at the first end of the housing and configured to receive an information-containing electrical signal. An optical output interface is positioned at the second end of the housing and configured to transmit a continuous wave optical beam. A tunable semiconductor laser is positioned in the interior space and operable to emit a laser beam having a selectable wavelength. A focusing lens assembly is positioned in the interior space along an optical path of the laser beam to operatively couple the laser beam to the optical output interface.

Abstract: A laser amplifier arrangement includes an optical pump source and an axially arranged laser oscillator-amplifier configuration pumped by the pump radiation. The laser oscillator-amplifier configuration includes a laser oscillator excitable by a portion of the pump radiation to emit a laser beam, and a laser amplifier that amplifies the laser beam using the pump radiation. The laser oscillator and laser amplifier are arranged in a substantially coaxial or collinear manner relative to a longitudinal axis of the laser oscillator-amplifier configuration. The pump source includes a first beam source for producing a first pump radiation to pump the laser oscillator, a second beam source for producing a second pump radiation for the laser amplifier, and a pump radiation conducting device, by means of which both the first and the second pump radiation can be lead into the laser oscillator-amplifier configuration substantially in the direction of the longitudinal axis for longitudinal pumping.

Abstract: In the case of a lens array type homogenizer optical system, the incident angle and intensity of a laser beam 1 entering a large-sized lens (long-axis condenser lens 22) of a long-axis condensing optical system, which is provided on the rear side, are changed for every shot by performing laser irradiation while long-axis lens arrays 20a and 20b are reciprocated in a direction corresponding to a long axial direction of a linear beam (X-direction). Therefore, vertical stripes are significantly reduced. Further, the incident angle and intensity of a laser beam 1 entering a large-sized lens (projection lens 30) of a short-axis condensing optical system, which is provided on the rear side, are changed for every shot by performing laser irradiation while short-axis lens arrays 26a and 26b are reciprocated in a direction corresponding to a short axial direction of a linear beam (Y-direction). Therefore, horizontal stripes are significantly reduced.

Abstract: A compact, light weight laser beam combiner includes a pair of concentric annular shells defining an annular cavity of an annular ring resonator having an annular solid laser gain medium disposed therein. The output ends of a plurality of low power and brightness fiber lasers are coupled into the cavity of the resonator such that fiber laser beams cause the gain medium in the resonator cavity to lase and produce an annular beam of laser light. Optical elements of the resonator are operable to feed a first portion of the laser light back through the resonator cavity to support regenerative lasing of the laser medium and to couple off a second portion of the laser light in the form of a circular beam of high power and high brightness laser light. A fluid may be circulated through the resonator cavity to cool the laser medium.

Abstract: One embodiment of a laser resonator comprises one or more laser resonator components, a container and an ozone generator. The laser resonator components include a non-linear crystal, a beam polarization combiner, an optical lens, a mirror and/or an optical grating. The container encloses the one or more laser resonator components. The ozone generator is configured to introduce ozone gas into the container.

Abstract: A surface emitting semiconductor laser includes a substrate, an n-type lower DBR, an n-type cavity extending region formed on the lower DBR, an active region formed on the cavity extending region, and an upper DBR formed on the active region. A difference in refractive index between a relatively high refractive index layer and a relatively low refractive in the upper DBR is smaller than that in the lower DBR.

Abstract: A nitride semiconductor laser element includes a laminate. The laminate includes on a substrate a first conductivity type nitride semiconductor layer, an active layer, and a second conductivity type nitride semiconductor layer, and constitutes a cavity resonator. The laminate includes an element region, an exposed region and an island layer. The element region is a region in which the laser element is formed. The exposed region is a region in which at least the first conductivity type nitride semiconductor layer is exposed on both sides of the element region in the cavity direction, and which is provided continuously in a cavity resonating direction of the laser element. The island layer is separated from the element region by the exposed region, and that is disposed in a corner of the nitride semiconductor laser element.

Abstract: The invention relates to a laser source with an external cavity generating a useful laser beam (Fu), that comprises at least one laser diode DL (10) mounted in an extended optical cavity (30, 82) defined between two reflecting surfaces (92, 48) forming an optical path for a laser beam Fd generated by the laser diode DL, a mode selection filter (44, 86) in the optical path of the cavity for selecting a resonance mode from a range of resonance modes of the laser beam in the cavity.

Abstract: A compact solid state laser that generates multiple wavelengths and multiple beams that are parallel, i.e., bore-sighted relative to each other, is disclosed. Each of the multiple laser beams can be at a different wavelength, pulse energy, pulse length, repetition rate and average power. Each of the laser beams can be turned on or off independently. The laser is comprised of an optically segmented gain section, common laser resonator with common surface segmented cavity mirrors, optically segmented pump laser, and different intra-cavity elements in each laser segment.

Abstract: An optical source including a laser source and a waveguide is provided. The laser source includes a laser cavity having a laser optical path length extending from a DBR grating to a reflective laser output facet, and emits an output beam at a fundamental wavelength. The waveguide includes an input facet and an output face. The waveguide extends along a waveguide optical length from the input facet of the waveguide to the output facet of the waveguide, and the waveguide is optically coupled to the laser source, thereby forming an external cavity having an optical path length extending from the reflective laser output facet to the input facet of the waveguide that is substantially equal to the laser optical path length.

Abstract: A multi-pass optical cell with an actuator for actuating a reflective surface is provided. In one preferred embodiment, an apparatus is provided comprising a first reflective surface, a second reflective surface, and a support structure supporting the first and second reflective surfaces. The support structure positions the first and second reflective surfaces to create an optical cell. The apparatus also comprises a source and a detector, which are positioned such that light emitted from the source is reflected in the optical cell at least one time between the first and second reflective surfaces before reaching the detector. The apparatus further comprises an actuator coupled with and operative to actuate the first reflective surface. In some embodiments, the actuator rotates the first reflective surface. Also, in some embodiments, the multi-pass optical cell is an open path multi-pass optical cell, while, in other embodiments, the multi-pass optical cell is a closed path multi-pass optical cell.

Abstract: Provided is a vertical cavity surface emitting laser that includes a plurality of laminated semiconductor layers including an active layer and that oscillates at a wavelength ?1, wherein a resonator is formed by upper and lower multilayer reflecting mirrors has a structure that generates a longitudinal multimode, and the first active layer is arranged at a position shifted from a standing wave loop of the first longitudinal mode. According to the vertical cavity surface emitting laser capable of suppressing oscillation of the second longitudinal mode with a large gain and capable of single longitudinal mode oscillation based on the first longitudinal mode, the longitudinal mode spacing is narrowed by increasing the length of the resonator for single transverse mode oscillation at a high output, and the single longitudinal mode oscillation is possible even if longitudinal multimode oscillation occurs.

Abstract: A radiation system includes a target material supply configured to supply droplets of target material along a trajectory, and a laser system that includes an amplifier and optics. The optics are configured to establish a first beam path which passes through the amplifier and through a first location on the trajectory, and to establish a second beam path which passes through the amplifier and through a second location on the trajectory. The laser system is configured to generate a first pulse of laser radiation when photons emitted from the amplifier are reflected along the first beam path by a droplet of target material at the first location on the trajectory. The laser system is configured to generate a second pulse of laser radiation when photons emitted from the amplifier are reflected along the second beam path by the droplet of target material at the second location on the trajectory.

Abstract: A multi-wavelength semiconductor laser device includes a block having a rectangular groove with a bottom face and two side faces extending in a predetermined direction; and laser diodes with different light emission wavelengths mounted on the bottom face and the side faces of the groove in the block so that their laser beams are emitted in the predetermined direction.

Abstract: In accordance with the present invention, a compact laser system with nearly continuous wavelength scanning is presented. In some embodiments, the compact laser system can be scanned over a broad range. In some embodiments, the compact laser system can be scanned at high scan rates. In some embodiments, the compact laser system can have a variable coherence length. In particular, embodiments with wavelength scanning over 140 nm with continuously variable scan rates of up to about 1 nm/?s, and discrete increase in scan rates up to about 10 nm/?s, and variable coherence lengths of from 1 mm to about 30 mm can be achieved.

Abstract: Methods and apparatus for improved single-mode selection in a quantum cascade laser. In one example, a distributed feedback grating incorporates both index-coupling and loss-coupling components. The loss-coupling component facilitates selection of one mode from two possible emission modes by periodically incorporating a thin layer of “lossy” semiconductor material on top of the active region to introduce a sufficiently large loss difference between the two modes. The lossy layer is doped to a level sufficient to induce considerable free-carrier absorption losses for one of the two modes while allowing sufficient gain for the other of the two modes. In alternative implementations, the highly-doped layer may be replaced by other low-dimensional structures such as quantum wells, quantum wires, and quantum dots with significant engineered intraband absorption to selectively increase the free-carrier absorption losses for one of multiple possible modes so as to facilitate single-mode operation.

Abstract: A surface-emitting laser device is disclosed that includes a substrate connected to a heat sink; a first reflective layer formed of a semiconductor distributed Bragg reflector on the substrate; a first cavity spacer layer formed in contact with the first reflective layer; an active layer formed in contact with the first cavity spacer layer; a second cavity spacer layer formed in contact with the active layer; and a second reflective layer formed of a semiconductor distributed Bragg reflector in contact with the second cavity spacer layer. The first cavity spacer layer includes a semiconductor material having a thermal conductivity greater than the thermal conductivity of a semiconductor material forming the second cavity spacer layer.

Abstract: In a cavity-dumped, repetitively-pulsed, solid-state laser cavity dumping is protracted over a predetermined time longer than a round-trip time of the resonator of the laser. The cavity dumping is effected by a Pockels cell optical switch. During a dumping period a voltage applied to the Pockels cell falls in a predetermined time. Varying the voltage fall-time varies the duration of pulses provided by the laser, independent of the pulse-repetition frequency.

Abstract: Systems, apparatus, devices and methods for pumping rod shaped solid state lasers with interchangeable arrays of diode laser pump sources that allows for rapid change of the diode laser array pump source without affecting or altering the solid state laser resonator. An embodiment includes a roof top structure having a light scattering reflection roof-top portion, sides with an interior specular reflecting surface and base opposite the top portion. The cavity includes a laser rod within the top portion of the structure positioned between opposing side walls, laser rod optics, and a pump source connected with the base plate to pump the laser rod. The pump cavity can include a mechanism for automating the rapid interchangeability of the pump source.

Abstract: Devices having whispering-gallery-mode (WGM) resonators configured to meet requirements of various applications and facilitate fabrication of such devices.

Abstract: Apparatus and methods for altering one or more spectral, spatial, or temporal characteristics of a light-emitting device are disclosed. Generally, such apparatus may include a volume Bragg grating (VBG) element that receives input light generated by a light-emitting device, conditions one or more characteristics of the input light, and causes the light-emitting device to generate light having the one or more characteristics of the conditioned light.

Abstract: A system and method for optical frequency conversion having asymmetric output include a coherent light apparatus. The coherent light apparatus includes a coherent light source that produces a first coherent light, a frequency converter optically coupled to the coherent light source, and a coupling optic optically coupled between the coherent light source and the frequency converter. The frequency converter converts the first coherent light to a second coherent light at a second frequency and includes an asymmetric frequency converter (AFC) that nonlinearly converts the first coherent light to the second coherent light with the frequency conversion being more efficient in a first direction than in a second direction. A resonant cavity formed about the AFC circulates the first coherent light and transmits the second coherent light propagating in the first direction.

Abstract: The present invention relates to external cavity laser (ECL) apparatuses and manufacturing processes, and more particularly to implementing low noise narrow bandwidth ECLs on planar lightwave circuit (PLC) platforms for harnessing high-performance, high-stability operation from a compact-footprint, low-power packaged device. An ECL device with narrow linewidth and low noise is disclosed, the device comprising a PLC device and a gain chip butt-coupled to each other. The PLC device has a planar Bragg grating (PBG) integrated onto a rectangular waveguide. The PLC device has anti-reflection coatings (ARC) on its input facet and output facet. The waveguide is designed to be selective of a single polarization. The gain chip has high-reflection coating (HRC) on a back facet and an ARC on a front facet. An operating wavelength of the ECL is aligned to a longer wavelength red slope of a reflectivity spectrum of the PBG. The operating wavelength may be tuned thermally, electrically, or thermo-electrically.

Abstract: The present invention relates to an apparatus for reading from and/or writing to holographic storage media, and more specifically to an apparatus for reading from and/or writing to holographic storage media having an improved overlap between one or more reference beams and an object beam or a reconstructed object beam. According to the invention, the apparatus has a common aperture arrangement of a reference beam and an object beam or a reconstructed object beam, wherein the focus of the reference beam is shifted relative to the focus of the object beam or the reconstructed object beam within a focal plane of the object beam or the reconstructed object beam inside or close to the holographic storage medium.

Abstract: Devices having whispering-gallery-mode (WGM) resonators configured to meet requirements of various applications and facilitate fabrication of such devices.

Abstract: A compact solid state laser that generates multiple wavelengths and multiple beams that are parallel, i.e., bore-sighted relative to each other, is disclosed. Each of the multiple laser beams can be at a different wavelength, pulse energy, pulse length, repetition rate and average power. Each of the laser beams can be turned on or off independently. The laser is comprised of an optically segmented gain section, common laser resonator with common surface segmented cavity mirrors, optically segmented pump laser, and different intra-cavity elements in each laser segment.

Abstract: A new broadband source having a discrete set of spectral emission lines having high peak power in each line is provided by placing a gain medium in a reflective cavity comprising reflective front and back surfaces. A cavity feedback factor less than unity is achieved by providing reflectivity of one surface substantially lower than the reflectivity of the other surface such that spontaneous emission in the gain medium is linearly amplified just below the lasing threshold. In an alternative arrangement, a movable external back surface placed at a prescribed distance from the gain medium provides a means to achieve a free spectral range and finesse of the emission lines to match a pitch of a detector array in a SD-OCT system. By simultaneously providing high power to each detector element of the array, sensitivity and imaging speed of SD-OCT system are significantly improved.

Abstract: An edge emitting semiconductor laser includes a semiconductor body, which has a waveguide region. The waveguide region has an active layer for generating laser radiation. The active layer is arranged between a first waveguide layer and a second waveguide layer. The waveguide region is arranged between a first cladding layer and a second cladding layer. The semiconductor body has a main region and at least one phase structure region in which is formed a phase structure for the selection of lateral modes of the laser radiation emitted by the active layer. The phase structure region is arranged outside the waveguide region or formed by a region in which a dopant is introduced or an intermixing structure is produced.

Abstract: A new broadband discrete spectrum light source comprising a gain medium placed in a feedback cavity is disclosed. A design for a feedback cavity including reflectors having raised-edge reflectivity is presented. Bandwidth enhancement is achieved by selectively enhancing the intensity of the discrete emission lines near the band edges of the gain medium spectrum. The bandwidth of a broadband discrete spectrum light source is further enhanced by digitally applying a spectral correction to each detected signal according to a predetermined correction profile. A combined effect of using a broadband discrete spectrum light source and applying spectral correction to the detected signal in an imaging system such as a Spectral Domain Optical Coherence Tomography (SD-OCT) imaging system, results in a desired spectral profile and a bandwidth necessary to achieve higher depth resolution for obtaining high quality diagnostic images.

Abstract: A photonic crystal that can spatially control the resonance efficiency and reduce the leakage of light in transversal directions and a surface emitting laser that can be formed by using such a photonic crystal are provided. The photonic crystal has a first region and a second region having a same periodic structure as fundamental structures thereof and defects are introduced into the periodic structure of the first region, which is arranged around the second region.