Tue, 12 Apr 2016 08:00:00 EDTA semiconductor laser produces infrared radiation suitable for jamming a heat seeking missile, wherein a wavelength of the radiation is in a range of 2-5 microns, and the laser has a semiconductor lasing medium of Pb1-xSexPb1-xSnxSe or Ga0.84In0.16As0.14Sb0.86. These materials can be doped to provide a p/n junction, wherein the laser is excitable by electric current passing through the p/n junction. The third one of these materials can be constructed also as a uniform undoped slab which is excitable optically. Cooling of the lasing medium is accomplished by use of a lithium heat sink thermally coupled to the lasing medium by a diamond thermal diffuser which conducts heat from the relatively small region of the laser to spread out the thermal energy along a relatively large surface of the heat sink. Modulation circuitry is connected to the excitation apparatus to provide a pulse train of the radiation.
Tue, 26 May 2015 08:00:00 EDTA light source for a photonic integrated circuit may comprise a reflection coupling layer formed on a substrate in which an optical waveguide is provided, at least one side of the reflection coupling layer being optically connected to the optical waveguide; an optical mode alignment layer provided on the reflection coupling layer; and/or an upper structure provided on the optical mode alignment layer and including an active layer for generating light and a reflection layer provided on the active layer. A light source for a photonic integrated circuit may comprise a lower reflection layer; an optical waveguide optically connected to the lower reflection layer; an optical mode alignment layer on the lower reflection layer; an active layer on the optical mode alignment layer; and/or an upper reflection layer on the active layer.
Tue, 26 May 2015 08:00:00 EDTA silicon-based thermal energy transfer apparatus that aids dissipation of thermal energy from a heat-generating device, such as an edge-emitting laser diode, is provided. In one aspect, the apparatus comprises a silicon-based base portion having a first primary surface and a silicon-based support structure. The silicon-based support structure includes a mounting end and a distal end opposite the mounting end with the mounting end received by the base portion such that the support structure extends from the first primary surface of the base portion. The support structure includes a recess defined therein to receive the edge-emitting laser diode. The support structure further includes a slit connecting the distal end and the recess to expose at least a portion of a light-emitting edge of the edge-emitting laser diode when the edge-emitting laser diode is received in the support structure.
Tue, 26 May 2015 08:00:00 EDTImproved brightness and feedback multi-emitter laser diode modules and methods are provided. A plurality of laser diode emitters emit broad-area light beams in a beam direction. In cross-section, each beam is broad in its slow axis and narrow in its fast axis. Groups of downstream optical components collimate, shape, stack and direct the beams along a light path towards a beam spot (which may be fiber-coupled). After collimating, stacking and directing, the beams are Fourier transformed in the fast-axis through a lens feature having a fast-axis focal length less than about 3 millimeters. In some embodiments, the fast-axis focal length is between about 0.1 and 2.0 millimeters. Astigmatism may be introduced between the fast axis and the slow axis in the beams upstream of the lens feature and in accordance with the fast axis focal length of the lens feature. The emitters may receive feedback including wavelength locking feedback.
Tue, 26 May 2015 08:00:00 EDTDisclosed is an ASE-free continuously tunable external resonator laser in which reduction in tuning range and decrease in output are suppressed. The external resonator laser comprises: a fixed support body which has a half mirror that partially reflects incident light and partially transmits incident light fixed therein; and a rotatory support body which is rotatably supported by the fixed support body by way of a shaft, and which has a laser chip that emits light, a collimator lens that collimates light emitted from the laser chip, and a diffraction grating that diffracts light emitted from the laser chip, fixed therein.
Tue, 26 May 2015 08:00:00 EDTThere is provided a surface emitting laser allowing a direction of a far-field pattern (FFP) centroid to be inclined from a normal direction of a substrate providing the surface emitting laser, comprising: a substrate; a lower reflecting mirror, an active layer, an upper reflecting mirror stacked on the substrate; and a surface relief structure located in an upper portion of a light emitting surface of the upper reflecting mirror, the surface relief structure being made of a material allowing at least some beams emitted from the surface emitting laser to be transmitted therethrough, a plurality of regions having a predetermined optical thickness in a normal direction of the substrate being formed in contact with other region in an in-plane direction of the substrate, and a distribution of the optical thickness in the in-plane direction of the substrate is asymmetric to a central axis of the light emitting regions.
Tue, 26 May 2015 08:00:00 EDTA device including one or more layers with lateral regions configured to facilitate the transmission of radiation through the layer and lateral regions configured to facilitate current flow through the layer is provided. The layer can comprise a short period superlattice, which includes barriers alternating with wells. In this case, the barriers can include both transparent regions, which are configured to reduce an amount of radiation that is absorbed in the layer, and higher conductive regions, which are configured to keep the voltage drop across the layer within a desired range.
Tue, 26 May 2015 08:00:00 EDTThe invention provides a laser converter for converting a laser radiation of shorter wavelength to a laser radiation of longer wavelength using a single stage conversion. The laser converter comprises a laser diode for emitting a laser radiation in a first wavelength range, a cylindrical microlens for transferring and focusing the laser radiation to a laser chip and the laser chip for absorbing the laser radiation and emitting the laser radiation in a second wavelength range.
Tue, 26 May 2015 08:00:00 EDTNovel methods and systems for miniaturized lasers are described. A photonic crystal is bonded to a silicon-on-insulator wafer. The photonic crystal includes air-holes and can include a waveguide which couples the laser output to a silicon waveguide.
Tue, 26 May 2015 08:00:00 EDTVarious embodiments of a photonic device and fabrication method thereof are provided. In one aspect, a device includes a substrate, a current confinement layer disposed on the substrate, an absorption layer disposed in the current confinement layer, and an electrical contact layer disposed on the absorption layer. The current confinement layer is doped in a pattern and configured to reduce dark current in the device. The photonic device may be a photodiode or a laser.
Tue, 26 May 2015 08:00:00 EDTA GRINSCH laser having an asymmetric configuration wherein the optical confinement is weighted more to the n-doped multilayer section than to the p-doped multilayer section. The GRINSCH laser can emit laser light at a wavelength λ=976 nm over a broad area with a beam power of 11.4 W at a 12 A bias current at a temperature of 20° C. Fabry-Perot and distributed Bragg reflector GRINSCH laser configurations are disclosed.
Tue, 26 May 2015 08:00:00 EDTA method to tune an emission wavelength of a laser diode (LD) finely is disclosed. The method first controls a temperature of the etalon filter in T1 or T2, where the transmittance of the etalon filter becomes 40 to 50%, assuming a height between the peak and the bottom of the periodic transmittance to be 100%, at the grid wavelength λ1 or λ2, respectively. Then, the temperature of the LD is adjusted such that the intensity of light emitted from the LD and transmitted through the etalon filter becomes 40 to 50%.
Tue, 26 May 2015 08:00:00 EDTA tunable laser source that includes multiple gain elements and uses a spatial light modulator in an external cavity to produce spectrally tunable output is claimed. Several designs of the external cavity are described, targeting different performance characteristics and different manufacturing costs for the device. Compared to existing devices, the tunable laser source produces high output power, wide tuning range, fast tuning rate, and high spectral resolution.
Tue, 26 May 2015 08:00:00 EDTA pulsed smaser includes at least one optical resonator and an optical pump. The at least one optical resonator includes opposing mirrors, a solid state gain medium having a masing frequency in a range of from about 50 GHz to about 1 THz, and a Q-switch, wherein the solid state gain medium and the Q-switch are optically arranged between the opposing mirrors. The optical pump is arranged to provide optical pump power to the solid state gain medium. The optical pump and the Q-switch are configured to generate pulsed masing in the solid state gain medium at the masing frequency at room temperature to provide output electromagnetic radiation at the masing frequency.
Tue, 26 May 2015 08:00:00 EDTAn exemplary illumination source for an inspection system includes a pulsed seed laser having a wavelength of approximately 1104 nm and a continuous wave, Raman seed laser having a wavelength of approximately 1160 nm. An optical coupler can combine outputs of the pulsed seed laser and the continuous wave, Raman seed laser. Pre-amplification stages can receive an output of the optical coupler. A power amplifier can receive an output of the pre-amplification stages. A sixth harmonic can be generated using the amplified, combined wavelength. Systems for inspecting a specimen such as a reticle, photomask or wafer can include one of the illumination sources described herein.
Tue, 26 May 2015 08:00:00 EDTA method for providing a feedback circuit for a three dimensional projector. First and second input devices and a sensor for determining the rotational speed of the second input device are provided. A control device for controlling the rotational speed of the second input device and a phase locked loop (PLL) are provided. A phase reference signal is created based on the signal rate of the first input device. A phase signal is created based on the rotational speed of the second input device. The PLL compares the phase reference signal and the phase feedback signal to determine whether the first input device and the second input device are synchronized. A signal is sent to the control device for the second input device to change the rotational speed of the second input device in response to determining that the first input device and the second input device are not synchronized.
Tue, 19 May 2015 08:00:00 EDTA vertical geometry light emitting diode is disclosed that is capable of emitting light in the red, green, blue, violet and ultraviolet portions of the electromagnetic spectrum. The light emitting diode includes a conductive silicon carbide substrate, an InGaN quantum well, a conductive buffer layer between the substrate and the quantum well, a respective undoped gallium nitride layer on each surface of the quantum well, and ohmic contacts in a vertical geometry orientation.
Tue, 19 May 2015 08:00:00 EDTFrequency standards based on mode-locked fiber lasers, fiber amplifiers and fiber-based ultra-broad bandwidth light sources, and applications of the same.
Tue, 19 May 2015 08:00:00 EDTA fiber coupled semiconductor device and a method of manufacturing of such a device are disclosed. The method provides an improved stability of optical coupling during assembly of the device, whereby a higher optical power levels and higher overall efficiency of the fiber coupled device can be achieved. The improvement is achieved by attaching the optical fiber to a vertical mounting surface of a fiber mount. The platform holding the semiconductor chip and the optical fiber can be mounted onto a spacer mounted on a base. The spacer has an area smaller than the area of the platform, for mechanical decoupling of thermally induced deformation of the base from a deformation of the platform of the semiconductor device. Optionally, attaching the fiber mount to a submount of the semiconductor chip further improves thermal stability of the packaged device.
Tue, 19 May 2015 08:00:00 EDTAn optical gain architecture includes a pump source and a pump aperture. The architecture also includes a gain region including a gain element operable to amplify light at a laser wavelength. The gain region is characterized by a first side intersecting an optical path, a second side opposing the first side, a third side adjacent the first and second sides, and a fourth side opposing the third side. The architecture further includes a dichroic section disposed between the pump aperture and the first side of the gain region. The dichroic section is characterized by low reflectance at a pump wavelength and high reflectance at the laser wavelength. The architecture additionally includes a first cladding section proximate to the third side of the gain region and a second cladding section proximate to the fourth side of the gain region.
Tue, 19 May 2015 08:00:00 EDTSinglet oxygen metastables can be formed. A catalytic coating is formed on an interior surface of a flow reactor, and an oxygen containing species is flowed into the flow reactor to produce singlet oxygen metastables by a chemical reaction in the presence of the catalytic coating.
Tue, 19 May 2015 08:00:00 EDTA communication module according to the present invention includes a substrate, a laser element and a light receiving element provided on a front surface of the substrate and separating from each other, a transparent resin package collectively sealing the laser element and the light receiving element, and a diffusion unit provided to be opposed to a light emitting surface of the laser element at a prescribed distance for diffusing a laser beam emitted by the laser element, while the distance T between the laser element and the light receiving element satisfies the following formula (1): T≧t1·tan θ+(t1+t2)·tan θ′ . . . (1) (in the formula (1), t1 represents the distance between the light emitting surface of the laser element and the diffusion unit, θ represents the maximum angle of emission of the laser element, t2 represents the difference between the height from the front surface of the substrate up to the light emitting surface and the height up to alight receiving surface of the light receiving element, and θ′ represents the maximum diffusion angle of the diffusion unit.)
Tue, 19 May 2015 08:00:00 EDTA third-order distributed feedback laser has an active medium disposed on a substrate as a linear array of segments having a series of periodically spaced interstices therebetween and a first conductive layer disposed on a surface of the active medium on each of the segments and along a strip from each of the segments to a conductive electrical contact pad for application of current along a path including the active medium. Upon application of a current through the active medium, the active medium functions as an optical waveguide, and there is established an alternating electric field, at a THz frequency, both in the active medium and emerging from the interstices. Spacing of adjacent segments is approximately half of a wavelength of the THz frequency in free space or an odd integral multiple thereof, so that the linear array has a coherence length greater than the length of the linear array.
Tue, 19 May 2015 08:00:00 EDTA semiconductor laser includes a semiconductor nanowire of a first conductivity type provided over a substrate, a light emitting layer provided around the semiconductor nanowire and insulated at an upper end and a lower end thereof, a cladding layer of a second conductivity type different from the first conductivity type, the cladding layer being provided at an outer periphery of the light emitting layer, a first electrode electrically coupled to an end portion of the semiconductor nanowire, a second electrode electrically coupled to an outer periphery of the cladding layer, a first reflection mirror provided at a one-end portion side of the semiconductor nanowire, and a second reflection mirror provided at the other end portion side of the semiconductor nanowire.
Tue, 19 May 2015 08:00:00 EDTTensile strained germanium is provided that can be sufficiently strained to provide a nearly direct band gap material or a direct band gap material. Compressively stressed or tensile stressed stressor materials in contact with germanium regions induce uniaxial or biaxial tensile strain in the germanium regions. Stressor materials may include silicon nitride or silicon germanium. The resulting strained germanium structure can be used to emit or detect photons including, for example, generating photons within a resonant cavity to provide a laser.
Tue, 19 May 2015 08:00:00 EDTA method for fabricating a group-III nitride semiconductor laser device stably supplies laser cavity mirrors having a low lasing threshold current through the use of a semi-polar plane. A blade 5g is forced down through a first region ER1 to keep the first region ER1 squeezed between a support member H2 and a movable member H1 together with a part of a protective sheet TF in contact with the first region ER1 while the tension generated in the area of the protective sheet TF in contact with the first region ER1 with the movable member H1 increases until the semi-polar principal surface SF at an end face EG1 of the first region ER1 tilts by a deflection angle THETA from the semi-polar principal surface SF of a second region ER2, and a force is thereby generated in the first region ER1 in a direction opposite to the direction of travel of the blade 5g toward the first region ER1. For example, an angle ALPHA is within the range of 71 degrees to 79 degrees, and the deflection angle THETA is within the range of 11 to 19.
Tue, 19 May 2015 08:00:00 EDTA method for generation of electromagnetic radiation has the following method steps: generation of electromagnetic radiation at a useful frequency,division of the electromagnetic radiation into a useful beam and a secondary beam,frequency shift of the electromagnetic radiation of the secondary beam,control of the useful frequency as determined by a manipulated variable, wherein the manipulated variable is derived from the frequency-shifted radiation of the secondary beam.
Tue, 19 May 2015 08:00:00 EDTAn apparatus comprising an optical medium, a power splitter coupled to the optical medium, a first delay line coupled to the power splitter such that the power splitter is positioned between the first delay line and the optical medium, a first comb reflector coupled to the first delay line such that the first delay line is positioned between the first comb reflector and the power splitter, and a second comb reflector coupled to the power splitter but not the first comb reflector and not the first delay line. A method comprising receiving an optical signal, splitting the optical signal into a first split optical signal and a second split optical signal, delaying the first split optical signal, tuning the delayed first split optical signal, tuning the second split optical signal, and delaying the tuned second split optical signal.
Tue, 19 May 2015 08:00:00 EDTA method for quasi-synchronous tuning of wavelength or frequency of grating external-cavity semiconductor laser and a corresponding semiconductor laser are provided. A grating or mirror is rotated around a quasi-synchronous tuning point (Pq) as rotation center, so as to achieve the frequency selections by grating and resonance cavity in quasi-synchronous tuning, wherein the angle of the line between the quasi-synchronous tuning point (Pq) and a conventional synchronous tuning point (P0) with respect to the direction of light incident on the grating is determined according to the angle difference between the incidence angle and diffraction angle of light on the grating. According to present invention, approximately synchronous tuning of laser is achieved with a simple and flexible design.
Tue, 19 May 2015 08:00:00 EDTA high power fiber laser system emitting a substantially diffraction limited beam with a Gaussian intensity profile includes a single mode (“SM”) neodymium fiber pump source outputting a SM pump light; a seed laser operative to emit a SM signal light at a wavelength greater than that of the pump light; a SM DWM receiving and multiplexing the SM pump and signal lights. The disclosed system further includes a booster fiber amplifier which is configured with a frustoconically-shaped ytterbium (“Yb”) doped core receiving the pump and signal lights and configured with a small diameter input end which supports only a SM and a large diameter output end which is capable of supporting the SM and high order modes (:HOM”). The booster further has a cladding surrounding and coextending with the core, the core being configured for having intensity profiles of respective SMs of pump and signal lights overlap one another so that an overlap integral substantially equals to one (1) along an entire length of the core. The SM of the light signal extracts substantially the entire energy from the pump mode leaving the HOMs without amplification necessary to affect a quality of the diffraction limited beam of the system in a MW peak power range and hundreds of watt average power range.
Tue, 19 May 2015 08:00:00 EDTAn EUV light generation system includes a driver laser comprising a master oscillator such as a semiconductor laser, a spatial filter, gas slab amplification devices, relay optical systems, and high-speed axial-flow amplifiers. The slab amplification devices include beam adjusting optical units disposed, respectively, at input and output sides of the slab amplifiers SA to convert the beam profile and/or polarization direction and/or an elongated direction of the beam profile with the slab amplifiers is parallel to a free space axis AF of the slab waveguides, i.e. parallel to the discharge electrodes.
Tue, 19 May 2015 08:00:00 EDTA terahertz light generation device 1 comprises a resonator structure 12 for intensifying incident light and outputting the intensified light and laser oscillation units 10, 11 for feeding the incident light into the resonator structure 12. The incident light comprises first and second incident light components having polarization states different from each other and frequencies different from each other. The laser oscillation units 10, 11 feed the resonator structure 12 with the first and second incident light components at an angle inclined from a principal surface in the resonator structure 12. The resonator structure 12 outputs light having a frequency corresponding to the difference between the respective frequencies of the first and second incident light components.
Tue, 19 May 2015 08:00:00 EDTA heat dissipation device of a light engine for a projector has a housing, a fan module, a light engine and a heat sink. The light engine is positioned in the housing and connected to the heat sink. The heat sink is positioned out of the housing. The housing has a fan-enclosed flow channel attached on an outer surface of the housing. The fan module is guided by the fan-enclosed flow channel to the heat sink to enhance heat dissipation efficiency of the light engine for the projector.
Tue, 12 May 2015 08:00:00 EDTAn intra-cavity frequency doubled OPS-laser includes a laser-resonator terminated by a plane mirror and a mirror-structure of an OPS-chip. The resonator is folded by three fold-mirrors. The fold-mirrors are supported on a vibration-isolation plate supported by isolation posts above a base-plate. The plane mirror and the mirror-structure of the OPS-chip are mounted back to back on opposite parallel surfaces of a mounting block. The mounting-block is supported on the base-plate and extends through an aperture in the vibration-isolation plate. Movement of the vibration-isolation plate with respect to the base-plate does not change the resonator length.
Tue, 12 May 2015 08:00:00 EDTThe invention relates to an optical resonator, laser apparatus and a method of generating a laser beam inside an optical resonator. The optical resonator (100) includes an optical cavity (102) and an optical element (104.1, 104.2) at either end thereof, operable to sustain a light beam (108) therein, characterized in that each optical element (104.1, 104.2) is a phase-only optical element operable to alter a mode of the beam (108) as it propagates along the length of the optical resonator (100), such that in use the beam (108) at one end of the optical resonator (100) has a Gaussian profile while the beam (108) at the other end of the optical resonator (100) has a non-Gaussian profile.
Tue, 12 May 2015 08:00:00 EDTA manufacturing method for an excimer laser that includes a reflective Echelle diffraction grating includes obtaining information of a wavelength of a light source, a blazed order, a repetitive pitch of the grating, a material of the grating, and a predefined orientation ratio B/A that is a ratio between that a diffraction efficiency A of the blazed order and a diffraction efficiency Bb of an order lower by one order than the blazed order, and determining an initial value of a blaze angle based upon these pieces of information.
Tue, 12 May 2015 08:00:00 EDTA method of manufacturing an optical semiconductor device including: forming a mesa structure including a first conductivity type cladding layer, an active layer and a second conductivity type cladding layer in this order on a first conductivity type semiconductor substrate, an upper most surface of the mesa structure being constituted of an upper face of the second conductivity type cladding layer; growing a first burying layer burying both sides of the mesa structure at higher position than the active layer; forming an depressed face by etching both edges of the upper face of the second conductivity type cladding layer; and growing a second burying layer of the first conductivity type on the depressed face of the second conductivity type cladding layer and the first burying layer.
Tue, 12 May 2015 08:00:00 EDTThe specification and drawings present an apparatus and a method for protecting lasers or other sources of high optical power from damage due to external sources of contamination using a concept of a sacrificial optical component and automatic laser shutdown based on a pressure indication of a substantial damage to the sacrificial optical component such as puncturing through that component.
Tue, 12 May 2015 08:00:00 EDTThe invention relates to solid state light source, a use of a driver circuit for driving a light emitting element (150) of a solid state light source, a method for driving a light emitting element (150) of a solid state light source and a corresponding computer program. The invention provides that for a large amount of an AC period the light emitting element (150) is directly supplied with the AC input directly forwarded by the driver circuit, wherein nevertheless it is prevented that power exceeding a desired level reaches the light emitting element (150). The invention is aimed at a realization with simplified components and/or reduced costs in comparison to known techniques.
Tue, 12 May 2015 08:00:00 EDTA temperature-compensated laser driving circuit for driving a laser component is provided. The temperature-compensated laser driving circuit includes: a temperature compensation circuit, configured to generate a second current based on a first current and a temperature-independent current; and a modulation current generating circuit, configured to generate a modulation current based on the second current, and calibrate optical power output of the laser component based on the modulation current. The first current is proportional to the absolute temperature. The second current and the first current have a slope relative to the absolute temperature respectively, and the slope of the second current relative to the absolute temperature is larger than of the slope of the first current relative to the absolute temperature.
Tue, 12 May 2015 08:00:00 EDTAn interposer (support substrate) for an opto-electronic assembly is formed to include a thermally-isolated region where temperature-sensitive devices (such as, for example, laser diodes) may be positioned and operate independent of temperature fluctuations in other areas of the assembly. The thermal isolation is achieved by forming a boundary of dielectric material through the thickness of the interposer, the periphery of the dielectric defining the boundary between the thermally isolated region and the remainder of the assembly. A thermo-electric cooler can be used in conjunction with the temperature-sensitive device(s) to stabilize the operation of these devices.
Tue, 12 May 2015 08:00:00 EDTImplementing a layered hyperbolic metamaterial in a vertical cavity surface emitting laser (VCSEL) to improve thermal conductivity and thermal dissipation thereby stabilizing optical performance. Improvement in the thermal management and power is expected by replacing the distributed Bragg reflector (DBR) mirrors in the VCSEL. The layered metamaterial structure performs the dual function of the DBR and the heat spreader at the same time.
Tue, 12 May 2015 08:00:00 EDTA conduction cooled high power semiconductor laser and a method for fabricating the same are provided. The conduction cooled high power semiconductor laser comprises a heat sink (2) and one or more semiconductor laser units (1). The semiconductor laser unit consists of a laser chip (3), a substrate (4) bonded to the laser chip for heat dissipation and electrical connection, and an insulation plate (5) soldered to the substrate for insulation and heat dissipation. The semiconductor laser unit is soldered on the heat sink with the insulation plate therebetween. The semiconductor laser unit may be tested, aged, and screened in advance, and thereby the yield of the lasers can be improved and the manufacturing costs can be reduced. The laser has desirable heat dissipation performance, high reliability, and is applicable to high temperature and other complex and volatile environments.
Tue, 12 May 2015 08:00:00 EDTThe laser mount arrangement can have a laser bar and a driver positioned adjacent to one another and secured against a connection face of a heat sink base. The heat sink base is connected to and forms a first electrical connection between the laser bar and the driver. A second electrical connection is also provided between the laser bar and the driver opposite the heat sink base, which can be in the form of a flexible metal sheet with a narrow upward fold. This arrangement can provide a low inductance path for the current.
Tue, 12 May 2015 08:00:00 EDTThe existing diodes in an LED or laser diode package are used to measure the junction temperature of the LED or laser diode. The light or laser emissions of a diode are switched off by removing the operational drive current applied to the diode package. A reference current, which can be lower the operational drive current, is applied to the diode package. The resulting forward voltage of the diode is measured using a voltage measurement circuit. Using the inherent current-voltage-temperature relationship of the diode, the actual junction temperature of the diode can be determined. The resulting forward voltage can be used in a feedback loop to provide temperature regulation of the diode package, with or without determining the actual junction temperature. The measured forward voltage of a photodiode or the emissions diode in a diode package can be used to determine the junction temperature of the emissions diode.
Tue, 12 May 2015 08:00:00 EDTA microlaser system includes an optical source, a microlaser, an actuator switch, and a photovoltaic power source. The microlaser, which includes a control element, is optically pumped by at least a portion of light emitted by the optical source. The actuator switch is configured to be activated by a triggering event. Furthermore, the photovoltaic power source is coupled in a series connection with the actuator switch and the control element, the series connection configured to connect the photovoltaic power source to the control element of the microlaser when the actuator switch is activated by the triggering event.
Tue, 12 May 2015 08:00:00 EDTA multi-color harmonic synthesized laser system for laser processing and a laser processing method using multi-color harmonic synthesized laser are disclosed. The multi-color harmonic synthesized laser system includes a laser source for providing a single laser wave, a converter for converting the single laser wave into a plurality of harmonic waves with different frequencies, and a modulating unit for modulating amplitudes and relative phases of the harmonic waves to form a plurality of modulated harmonic waves, so as to synthesize the modulated harmonic waves as a single synthesized laser wave, wherein the single synthesized laser wave is focused on an object to perform a laser processing. The converter includes a plurality of non-linear crystals for converting the single laser wave into a fundamental harmonic wave and a plurality of multi-frequency harmonic waves. The harmonic waves are coherent and collinear, and the phases of the harmonic waves are related to one another.
Tue, 12 May 2015 08:00:00 EDTImplementations and examples of fiber lasers based on fiber laser cavity designs that produce self-similar pulses (“similaritons”) to achieve a pulse spectral bandwidth greater than a gain spectral bandwidth based on a spectral broadening fiber segment and a spectral filter to ensure the proper similariton conditions.
Tue, 12 May 2015 08:00:00 EDTAn optical active fiber is configured with an asymmetrically-shaped core having at least one long axis and a shortest axis which extends transversely to the long axis. The outmost cladding of the active fiber is configured with a marking indicating the orientation of the short axis. The marking allows for bending the fiber so that the shortest axis extends along and lies in the plane of the bend thereby minimizing distortion of a mode which is guided by the asymmetrically-shaped core as light propagates along the bend.
Tue, 12 May 2015 08:00:00 EDTEmbodiments relate to an all fiber passively Q-switched laser. The laser includes a large core doped gain fiber having a first end. The large core doped gain fiber has a first core diameter. The laser includes a doped single mode fiber (saturable absorber) having a second core diameter that is smaller than the first core diameter. The laser includes a mode transformer positioned between a second end of the large core doped gain fiber and a first end of the single mode fiber. The mode transformer has a core diameter that transitions from the first core diameter to the second core diameter and filters out light modes not supported by the doped single mode fiber. The laser includes a laser cavity formed between a first reflector positioned adjacent the large core doped gain fiber and a second reflector positioned adjacent the doped single mode fiber.