Abstract: A widely tunable laser is described where a compound semiconductor gain chip is coupled to a waveguide filter fabricated on silicon. The filter has two resonators with different free-spectral-ranges, such that Vernier tuning between the filters can be used to provide a single wavelength of light feedback into the gain chip, where the wavelength is adjustable over a wide range. The coupling between the gain chip and the filter is realized through a microlens whose position can be adjusted using micromechanics and locked in place.

Abstract: An optical measurement device includes a light source unit including a first laser light source configured to emit a laser beam having a first wavelength and a second laser light source configured to emit a laser beam having a second wavelength, a measurement wave number setting unit, and a light source adjustment unit configured to adjust at least one of the first wavelength and the second wavelength such that a difference between or a sum of a first wave number corresponding to the first wavelength and a second wave number corresponding to the second wavelength matches a measurement wave number set through the measurement wave number setting unit.

Abstract: A novel broadly tunable optical parametric oscillator is described for use in numerous applications including multi-photon microscopy. The optical parametric oscillator includes at least one sub-picosecond laser pump source configured to output a pump signal having a wavelength of about 650 nm or less and at least one type II optical parametric oscillator in optical communication with the pump source and configured to generate a single widely tunable pulsed optical signal. In one application, an optical system is in optical communication with the optical parametric oscillator and configured to direct at least a portion of the optical signal to a specimen, and at least one analyzing device is configured to receive a signal from the specimen in response to the optical signal.

Abstract: A method to tune an emission wavelength of a wavelength tunable LD is disclosed. The wavelength tunable LD includes two regions each providing micro heaters to modify the refractive index of micro regions provided with power. The method periodically detects a difference between the emission wavelength and the target wavelength. This wavelength difference is converted into power next supplied to respective micro heaters independently.

Abstract: The present disclosure relates to a compact external cavity tunable laser apparatus. The laser apparatus includes a substrate, an external cavity tunable reflecting unit that reflects laser light entering from the outside on the substrate and selects and varies a wavelength of the reflected laser light, an optical fiber that outputs the laser light on the substrate; and an highly integrated light source that integrates the laser light input from the external cavity tunable reflecting unit using inclined input and output waveguides, a curved waveguide, and a straight waveguide to output the integrated laser light to the optical fiber in order to match an optical axis formed with the external cavity tunable reflecting unit with an optical axis formed with an optical fiber.

Abstract: A laser apparatus may include a master oscillator, an optical unit provided in a beam path of a laser beam from the master oscillator, a beam adjusting unit provided upstream from the optical unit in a beam path of the laser beam and configured for adjusting at least one of a beam path and a wavefront of the laser beam, a first detection unit provided between the beam adjusting unit and the optical unit in a beam path of the laser beam and configured for detecting the laser beam, a second detection unit provided downstream from the optical unit in a beam path of the laser beam and configured for detecting the laser beam, and a controller configured for controlling the beam adjusting unit based on outputs from the first and second detection units.

Abstract: A laser comprises a front mirror (FM), a gain section coupled to the FM, a phase section coupled to the gain section such that the gain section is positioned between the phase section and the FM, and a back mirror (BM) comprising an interferometer and coupled to the phase section such that the phase section is positioned between the BM and the gain section. A method comprises splitting a first light into a second light and a third light, reflecting the second light to form a second reflected light, reflecting the third light to form a third reflected light, and causing the second reflected light and the third reflected light to interfere and combine to form a combined light to narrow a reflectivity peak spectrum width.

Abstract: A method for wavelength tunable output from a broadband spectrum using a quasi phase-matched optical parametric amplifier/difference frequency generator (CQPM OPA/DFG)-based apparatus involves changing the relative timing of a pump pulse with respect to a seed pulse. The temporal variation varies the location of the spatial/temporal overlap of the spectrally narrow pump pulse over the spectrally broad seed spectrum occurring within the CQPM nonlinear medium. This overlap position determines the portion of the seed pulse that is phase-matched as the signal in the OPA or the seed for DFG. Piezo-electric fiber stretchers may be employed to vary the relative pulse timing and enables tuning of the output from the OPA or DFG without the use of any moving parts. Associated apparatus is disclosed.

Abstract: Described herein is a laser (1) having a cavity for supporting oscillation of an electromagnetic signal to provide lasing action. A gain element (5) provides a source of stimulated emission for amplifying the oscillating signal. The laser also includes a wavelength selective element (7), which includes a reflecting element and a polarization modifying element. The reflecting element selectively defines a predetermined wavelength and the polarization modifying element selectively modifies the polarization of the signal component at the predetermined wavelength so as to provide high selectivity. The wavelength selective element (7) rotates the signal polarization at the predetermined wavelength into an orthogonal state. A polarization filter (9) filters out the signal components having wavelengths not corresponding to the predetermined wavelength and a polarization rotation element (11) again rotates the polarization of the signal into an orthogonal state.

Abstract: Provided is a wavelength variable laser device wherein an SOA is simplified. The wavelength variable laser device includes: an optical filter formed on a PLC; an SOA that supplies light to the optical filter; a light reflecting section that returns the light transmitted through the optical filter to the SOA via the optical filter; optical waveguides which are formed on the PLC and connect the SOA, the optical filter, and the light reflecting section; a wavelength variable section that changes a wavelength of the light transmitting through the optical filter; and a phase variable section that changes a phase of the light propagated on the optical waveguides.

Abstract: A beam-stabilized laser system using optical frequency conversion in a nonlinear optical crystal is disclosed. An optimal phase-matching angle in the crystal depends on both wavelength and temperature. If the crystal temperature changes, the optimal phase-matching direction will change as well. A different wavelength can be selected so that the optimal phase-matching occurs along the original beam path and returns the output beam to the original direction. Thus, a central wavelength of the laser beam illuminating the nonlinear optical crystal can be slightly adjusted to compensate for the pointing drift. Since the illuminating wavelength can normally be tuned much faster than the crystal temperature, a more agile and responsive pointing stabilization can be achieved.

Abstract: An apparatus includes a laser that generates a predetermined wavelength when the laser operates at room temperature, the predetermined wavelength being offset from a specific wavelength. The laser has a controlled wavelength range due to a wavelength drift, the wavelength range having a first wavelength as the upper boundary and a second wavelength as the lower boundary, the first wavelength is generated when the laser operates at a first temperature of an ambient and the second wavelength is generated when the laser operates at a predetermined temperature higher than a second temperature of the ambient. The apparatus includes a heater that heats the laser such that a wavelength in the controlled wavelength range that is generated by the laser when heated by the heater from the second temperature is longer than a short wavelength that is generated by the laser centered on the specific wavelength that operates at the second temperature; and a control circuit configured to turn on the heater.

Abstract: A method and device are provided for fast, continuous tuning of an optical source. A first pump signal with a first pump frequency is input into a mixer along with a first seed signal having a first seed frequency. Within the mixer, the first pump signal and the first seed signal generate at least one idler having an idler frequency defined as two times the pump frequency minus the seed frequency. Shifting the pump signal across a frequency range at a sweep rate causes the idler frequency to be shifted by two times the frequency range at two times the sweep rate. The shifted at least one idler is mixed with the shifted pump signal to generate a first mix product that has two times the sweep rate and frequency range of the pump signal.

Abstract: A modular ultrafast pulse laser system is constructed of individually pre-tested components manufactured as modules. The individual modules include an oscillator, pre-amplifier and power amplifier stages, a non-linear amplifier, and a stretcher and compressor. The individual modules can typically be connected by means of simple fiber splices.

Abstract: The present application provides an optical comb source in which the comb is produced by seeding a gain switched Fabry-Pérot laser with light from a single mode laser, whilst at the same time driving the Fabry-Pérot laser with a DC bias and RF signal.

Abstract: The invention relates to an external cavity wideband tunable laser with dual laser gain media coupled by a polarization beam combiner. The laser comprises a first laser gain medium, a first laser cavity end mirror arranged on the first laser gain medium, a first intracavity collimating lens, an active optical phase modulator, a tunable acousto-optic filter, an intracavity reflection mirror, an etalon and a total reflection mirror which are arranged on the opposite side of the tunable acousto-optic filter from the intracavity reflection mirror inside a laser cavity.

Abstract: A laser device (100) includes a laser (110; 210; 310; 410; 510) in turn including at least one Distributed Bragg Reflector (DBR) section (111), at least one phase section (112) and at least one gain section (113), further including a laser control element (150), a feedback control element (140) and a frequency noise discriminator (130,131), which feedback control element is arranged to feed a variable feedback signal to at least one of the at least one DBR section and the at least one phase section of the laser, so that the output laser frequency is altered in response to a variation in the feedback signal or the combination of respective feedback signals, whereby the feedback signal or combination of respective feedback signals is varied as a function of the detected frequency fluctuation so as to counteract the detected frequency fluctuation.

Abstract: Described herein is a tunable optical filter (1). The filter includes a phase manipulation layer in the form of a liquid crystal material (3) and a diffractive layer in the form of a diffraction grating (5) sandwiched between an upper glass layer (7) and lower silicon layer (9). Grating (5) includes a grating structure (11) etched therein for angularly diffracting an input optical signal into a plurality of constituent wavelength components according to wavelength. Material (3) includes a two-dimensional array of independently addressable pixels (13), each pixel configured for receiving a drive signal and, in response to the drive signal, selectively modifying the phase of the wavelength components incident onto each pixel to directionally steer the components along respective angularly separated paths. By suitable steering of the wavelength components, at least one wavelength component is coupled along a predetermined collection path to an optical system such as a laser cavity.

Abstract: A cable television transmitter includes a substrate including a silicon material, control electronics disposed in the substrate, and a gain medium coupled to the substrate. The gain medium includes a compound semiconductor material. The cable television transmitter also includes an optical modulator optically coupled to the gain medium and electrically coupled to the control electronics, a waveguide disposed in the substrate and optically coupled to the gain medium, a first wavelength selective element characterized by a first reflectance spectrum and disposed in the substrate, and a second wavelength selective element characterized by a second reflectance spectrum and disposed in the substrate. The cable television transmitter further includes an optical coupler disposed in the substrate and joining the first wavelength selective element, the second wavelength selective element, and the waveguide and an output mirror.

Abstract: Systems, methods and computer-accessible mediums for providing a radiation(s) can be provided. For example, a hardware arrangement can be configured to provide the radiation(s) that can have a wavelength(s) that continuously changes over time and over a predetermined bandwidth with a predetermined envelope in a single sweep. The hardware arrangement can include a gain arrangement and a controller arrangement, and the controller arrangement can be configured to electronically control the gain arrangement such that the wavelength(s) provided by the hardware arrangement (i) spans a subset of the predetermined bandwidth, or (ii) changes a wavelength dependent distribution in the single sweep.

Abstract: A system (10, 20) and method including a wavelength tuning mechanism and a laser path length tuning mechanism for reducing discontinuities in a sweep range. A processor (14) is coupled to a wavelength monitoring device (18) and the tuning mechanisms. The processor analyzes data from the wavelength monitor to adjust the wavelength tuning and cavity length tuning at discontinuities in the wavelength sweep to reduce the discontinuities.

Abstract: A wavelength-tunable light source includes light sources having differing variable wavelength regions, where light sources having adjacent wavelength regions are distributed to different systems. The light sources are each set such that an end portion of the variable wavelength region of the light source overlaps an end portion of the variable wavelength region of another light source. A control unit selects and drives a first light source of a first system, varies a wavelength of the first light source, selects a second light source that is of a second system among the different systems and that has a wavelength region overlapping the variable wavelength region of the first light source, drives the second light source concurrently with the first light source and subsequently switches to the output light of the second light source, causing wavelength variation and executing continuous wavelength variation over a wide range.

Abstract: A spatially modulated waveguide Bragg grating mirror is suspended over a substrate by plurality of fingers extending laterally away from the waveguide centerline. The positions of the fingers are coordinated with the positions of crests and valleys of amplitude or phase modulation of the Bragg grating, to avoid disturbing the Bragg grating when it is tuned by heating. When the Bragg grating is heated, the heat flows through the fingers creating a quasi-periodic refractive index variation along the Bragg grating due to quasi-periodic temperature variation created by the heat flow from the grating through the supporting fingers. Due to coordination of the positions of supporting fingers with positions of the crests and valleys of modulation, the optical phase coherence is maintained along the Bragg grating, so that the spectral lineshape or filtering property of the Bragg grating is substantially preserved.

Abstract: A widely tunable multi-mode semiconductor laser containing only two electrically active sections, being an optical gain section and a tunable distributed Bragg reflector section adapted to reflect at a plurality of wavelengths, wherein the gain section is bounded by the tunable distributed Bragg reflector section and a broadband facet reflector, and wherein the tunable distributed Bragg reflector section comprises a plurality of discrete segments capable of being selectively tuned, wherein the reflection spectra of one or more segments of the tunable distributed Bragg reflector section can be tuned lower in wavelength to reflect with the reflection spectrum of a further segment of the tunable distributed Bragg reflector section to provide a wavelength range of enhanced reflectivity. An optical transmitter comprising a light source that is such a widely tunable multi-mode semiconductor laser.

Abstract: A monolithically integrated, tunable semiconductor laser with an optical waveguide, comprising epitaxial layers on a substrate and having first and second reflectors bounding an optical gain section and a non-driven region, wherein at least one of the reflectors is a distributed Bragg reflector section configured to have a tunable reflection spectrum, wherein control electrodes are provided to at least the optical gain section, and the distributed Bragg reflector section, and wherein the non-driven region has a length of at least 100 ?m, is without an electrical contact directly contacting onto the epitaxially grown side of the non-driven region, and the non-driven region is without a reflective Bragg grating within the epitaxial layers of the non-driven region.

Abstract: A Fabry-Pérot tunable filter device is described with reflecting elements separated by an optical path length to form an optical resonator cavity. A first actuator means is directly or indirectly coupled with a first reflecting element. And the first actuator means is configured to modulate the optical path length between first and second reflecting elements by a modulation amplitude to thereby sweep the optical resonator cavity through a band of optical resonance frequencies with a sweep frequency of 70 kHz or more. And the mechanical coupling between selected elements of the arrangement is sufficiently low such that when operated at the sweep frequency, the selected elements act as a system of coupled oscillating elements. In addition or alternatively, the first actuator means is directly or indirectly coupled with the first reflecting element so as to substantially drive the first reflecting element only.

Abstract: This description relates to an apparatus, a method of manufacturing, and a method of tuning optical and/or electrical parameters of semiconductor devices and materials, thin film materials, or other devices. In one example, a laser is tuned to produce an adjustable output wavelength by coupling the laser to a tuning material or base such as, for example, a piezoelectric base using a suitable attachment method. The laser includes of a tunable material that is sensitive to stress and/or strain. Stress and/or strain applied to the laser from the tuning material results in an electronically variable output wavelength. As an example, applying a voltage to a piezoelectric base that serves as a tuning material can cause the base to expand or contract, and the expansions and contractions from the base are coupled to the tunable material of the laser, thus varying the wavelength of the output light from the laser.

Abstract: A light radiating device capable of reducing production costs and preventing sealing defects for a display device, and a method of fabricating an organic light emitting diode (OLED) display device using the same are provided. The light radiating device includes a light source to generate light and a light modifier, including a transmissive region and a non-transmissive region, that define an exposure region on a substrate. The method includes applying a frit to at least one of a first substrate having a pixel region and a second substrate, plasticizing the frit, and aligning the first substrate, the second substrate, and a light radiating device to define an exposure region on the at least one of the first substrate and the second substrate, and radiating the light to the frit to couple the first substrate and the second substrate.

Abstract: A diode laser assembly including a plurality of diode bars disposed on a generally flat base plate and being oriented to emit a plurality of laser beams in a first direction. A reflector is spaced in the first direction from each of the diode bars in the first. Each reflector has at least two reflecting surfaces, one for reflecting the laser beams into a second direction different from the first direction and the other for reflecting the laser beams into a third direction different from the first and second directions to produce a spatially combined laser beam. Each reflector is moveable relative to one another and to the diode bars for adjusting the individual laser beams within the spatially-combined laser beam for optimizing the quality of the spatially combined laser beam.

Abstract: A high-speed, single-mode, high power, reliable and manufacturable wavelength-tunable light source operative to emit wavelength tunable radiation over a wavelength range contained in a wavelength span between about 950 nm and about 1150 nm, including a vertical cavity laser (VCL), the VCL having a gain region with at least one compressively strained quantum well containing Indium, Gallium, and Arsenic.

Abstract: Various implementations of the invention compensate for “phase wandering” in tunable laser sources. Phase wandering may negatively impact a performance of a lidar system that employ such laser sources, typically by reducing a coherence length/range of the lidar system, an effective bandwidth of the lidar system, a sensitivity of the lidar system, etc. Some implementations of the invention compensate for phase wandering near the laser source and before the output of the laser is directed toward a target. Some implementations of the invention compensate for phase wandering in the target signal (i.e., the output of the laser that is incident on and reflected back from the target). Some implementations of the invention compensate for phase wandering at the laser source and in the target signal.

Abstract: In some embodiments, the instant invention provides for a system that includes at least the following components: (i) an Alexandrite laser pumping subsystem; where the Alexandrite laser pumping subsystem is configured to: 1) produce wavelengths between 700 and 820 nm, and 2) produce a pump pulse having: i) a duration between 1 to 10 milliseconds, and ii) an energy measuring up to 100 Joules; where the Alexandrite laser pumping subsystem includes: 1) an optical fiber, and 2) a Lens system, (ii) a Thulium doped Yttrium Aluminum Garnet (Tm:YAG) laser subsystem; where the Tm:YAG laser subsystem includes: 1) a Tm:YAG gain medium, 2) a rod heat sink, and 3) at least one cooling device, (iii) a wavelength selecting device, where the wavelength selecting device is configured to deliver a wavelength between 1.75 microns to 2.1 microns; and where the system is configured to produce a high energy conversion efficiency.

Abstract: A method for generating high power electromagnetic radiation based on double-negative metamaterial (DNM), includes providing electrons of an electron beam moving in a vacuum close to an interface between the DNM and the vacuum at a predetermined average speed larger than a phase velocity of an electromagnetic wave propagating in the DNM so as to generate coherent high power radiation. The method can be applied but not limited to high power and compact Terahertz radiation sources and Cherenkov particle detectors and emitters.

Abstract: A method for wavelength tunable output from a broadband spectrum using a quasi phase-matched optical parametric amplifier/difference frequency generator (CQPM OPA/DFG)-based apparatus involves changing the relative timing of a pump pulse with respect to a seed pulse. The temporal variation varies the location of the spatial/temporal overlap of the spectrally narrow pump pulse over the spectrally broad seed spectrum occurring within the CQPM nonlinear medium. This overlap position determines the portion of the seed pulse that is phase-matched as the signal in the OPA or the seed for DFG. Piezo-electric fiber stretchers may be employed to vary the relative pulse timing and enables tuning of the output from the OPA or DFG without the use of any moving parts. Associated apparatus is disclosed.

Abstract: The tunable light source structure proposed in the present invention has an advantage in that a limitation on a typical technology not simultaneously satisfying high-speed tuning and wide range tuning is overcome and thus it is possible to simultaneously satisfy high-speed tuning slower than or equal to several ns and 100 nm-level wide range tuning. Also, a driving method is simpler than that of a typical technology, a stable operation is possible, and it is possible to lower a manufacturing cost of all modules including a driving circuit. In implementing the SLD and the AMZI-FP that are key components of the tunable light source structure of the present invention, an Si or polymer optical waveguide as well as III-group to V-group materials (GaAs, InP and GaSb) may also be employed.

Abstract: The multi-wavelength laser is a ring laser source working at room temperature. The laser has an inner cavity disposed in an outer cavity. A pair of circulators disposed in the inner cavity is configured to assure counter-propagation of light between the inner cavity and the outer cavity. A gain-clamped semiconductor optical amplifier (GC-SOA) is formed by combining a SOA and a Fiber Fabry-Perot Tunable Filter (FFP-TF) with the circulator pair. This configuration in the laser cavity results in an improvement in terms of transient gain excursions by applying an optical feedback. This attribute of the GC-SOA enables realizing a stable multi-wavelength laser source.

Abstract: Techniques, devices and systems for optical communications based on wavelength division multiplexing (WDM) that use tunable multi-wavelength laser transmitter modules.

Abstract: A tunable optical system with hybrid integrated semiconductor laser is provided. The optical system includes a silicon-on-insulator (SOI) substrate; a first optical waveguide tunable comb filter formed at the first side of the SOI substrate; a second optical waveguide tunable comb filter with detuned filter response formed at the first side of the SOI substrate; an etched laser pit at the first side of the SOI substrate; a plurality of spacers formed on the bottom surface of the laser pit near the plane of the first side of the SOI substrate; a plurality of bumping pads formed on the bottom surface of the laser pit near the plane of the first side of the SOI substrate; and a laser chip flip-chip bonded at the first side of the SOI substrate supported by the spacers. Heating sections may be provided on the filters to tune the filters.

Abstract: A tunable laser, including: a laser resonant cavity; a laser gain medium; an intra-cavity collimating lens; an acousto-optic tunable filter; a device exciting sound waves in an acousto-optic crystal; a radio frequency signal source providing radio frequency energy for the energy transducer and adjusting the oscillation wavelength of the laser resonant cavity by changing radio signal frequency; an optical phase modulator disposed between the intra-cavity collimating lens and the acousto-optic crystal; an optical etalon disposed between the optical phase modulator and the laser gain medium; a wavelength locker disposed at one of zero-order diffraction optical paths of intra-cavity light; a pigtailed collimator coupling laser output light to an optical fiber; a pumping source exciting the laser gain medium; a phase modulator driver for driving the optical phase modulator; and a signal control processing circuit.

Abstract: Method in which, in order to actuate a wavelength-tunable laser diode in a spectrometer, a power-time function is predetermined instead of a current-time function, wherein the laser diode is tuned periodically over a wavelength range in accordance with the power-time function. For this purpose, a current profile (i) with which the laser diode is actuated is determined from the power-time function and measured values of the voltage (u) present at the laser diode.

Abstract: A laser mux assembly generally includes a back reflector selectively coupled to one of the input ports of an optical multiplexer, such as an arrayed waveguide grating (AWG), and at least one laser emitter coupled to an output port. The laser emitter may include a gain region that emits light across a plurality of wavelengths including, for example, channel wavelengths in an optical communication system. The emitted light is coupled into the output port and the AWG or optical multiplexer filters the emitted light from the laser emitter at different channel wavelengths. The back reflector reflects the filtered light at the respective channel wavelength such that lasing occurs at the channel wavelength(s) of the reflected, filtered light. The laser mux assembly may be used, for example, in a tunable transmitter, to generate an optical signal at a selected channel wavelength.

Abstract: The multi-wavelength laser is a ring laser source working at room temperature. The laser has an inner cavity disposed in an outer cavity. A pair of circulators disposed in the inner cavity is configured to assure counter-propagation of light between the inner cavity and the outer cavity. A gain-clamped semiconductor optical amplifier (GC-SOA) is formed by combining a SOA and a Fiber Fabry-Perot Tunable Filter (FFP-TF) with the circulator pair. This configuration in the laser cavity results in an improvement in terms of transient gain excursions by applying an optical feedback. This attribute of the GC-SOA enables realizing a stable multi-wavelength laser source.

Abstract: In at least one embodiment of the wavelength-tunable light source (1), it comprises an output source (2), which is capable in operation of generating electromagnetic radiation (R). Furthermore, the light source (1) has a wavelength-selective first filter element (5), which is situated downstream from the output source (2). Moreover, the light source (1) contains a first amplifier medium (3), which is situated downstream from the first filter element (5) and is capable of at least partial amplification of the radiation (R) emitted by the output source (2). The light source (1) further comprises at least one wavelength-selective second filter element (6), which is situated downstream from the first amplifier medium (3), the second filter element (6) having an optical spacing (L) to the first filter element (5). The first filter element (5) and the at least one second filter element (6) are tunable via a control unit (11), which the light source (1) has.

Abstract: A method and apparatus for stabilizing the seed laser in a laser produced plasma (LPP) extreme ultraviolet (EUV) light system are disclosed. In one embodiment, the cavity length of the laser may be adjusted by means of a movable mirror forming one end of the cavity. The time delay from the release of an output pulse to the lasing threshold next being reached is measured at different mirror positions, and a mirror position selected which results in a cavity mode being aligned with the gain peak of the laser, thus producing a minimum time delay from an output pulse of the laser to the next lasing threshold. A Q-switch in the laser allows for pre-lasing and thus jitter-free timing of output pulses. Feedback loops keep the laser output at maximum gain and efficiency, and the attenuation and timing at a desired operating point.

Abstract: An integrated circuit includes an optical source that provides an optical signal to an optical waveguide. In particular, the optical source may be implemented by fusion-bonding a III-V semiconductor to a semiconductor layer in the integrated circuit. In conjunction with surrounding mirrors (at least one of which is other than a distributed Bragg reflector), this structure may provide a cavity with suitable optical gain at a wavelength in the optical signal along a vertical direction that is perpendicular to a plane of the semiconductor layer. For example, the optical source may include a vertical-cavity surface-emitting laser (VCSEL). Moreover, the optical waveguide, defined in the semiconductor layer, may be separated from the optical source by a horizontal gap in the plane of the semiconductor layer. During operation of the optical source, the optical signal may be optically coupled across the gap from the optical source to the optical waveguide.

Abstract: An extreme ultraviolet light source apparatus comprises a laser apparatus having a master oscillator outputting one or more longitudinal-mode-laser lights, an amplifier with a molecular gas as an amplifying agency amplifying a longitudinal-mode laser light of which wavelength is included in one of amplifiable lines, and a controller adjusting the master oscillator so that the wavelength of the longitudinal-mode laser light outputted from the master oscillator is included in one of the amplifiable lines, the laser apparatus being used as a driver laser, wherein the laser apparatus irradiates a target material with a laser light for generating plasma, and the extreme ultraviolet light is emitted from the plasma and outputted from the extreme ultraviolet light source apparatus.

Abstract: An optical coherence tomography system utilizes an optical swept laser that has cavity length compensator that changes an optical length of the laser cavity for different optical frequencies to increase the length of the laser cavity for lower optical frequencies. Specifically, a spectral separation between longitudinal cavity modes of the laser cavity is shortened or alternatively lengthened as a passband of a cavity tuning element sweeps through a scanband of the swept optical signal. In some examples, the compensator is implemented as two gratings. In others, it is implemented as a chirped grating device.

Abstract: Compact optical frequency sources are described. The comb source may include an intra-cavity optical element having a multi-material integrated structure with an electrically controllable active region. The active region may comprise a thin film. By way of example, the thin film and an insulating dielectric material disposed between two electrodes can provide for rapid loss modulation. In some embodiments the thin film may comprise graphene. In various embodiments of a frequency comb laser, rapid modulation of the CEO frequency can be implemented via electric modulation of the transmission or reflection loss of an additional optical element, which can be the saturable absorber itself. In another embodiment, the thin film can also be used as a saturable absorber in order to facilitate passive modelocking. In some implementations the optical element may be formed on a cleaved or polished end of an optical fiber.

Abstract: This description relates to an apparatus, a method of manufacturing, and a method of tuning optical and/or electrical parameters of semiconductor devices and materials, thin film materials, or other devices. In one example, a laser is tuned to produce an adjustable output wavelength by coupling the laser to a tuning material or base such as, for example, a piezoelectric base using a suitable attachment method. The laser includes of a tunable material that is sensitive to stress and/or strain. Stress and/or strain applied to the laser from the tuning material results in an electronically variable output wavelength. As an example, applying a voltage to a piezoelectric base that serves as a tuning material can cause the base to expand or contract, and the expansions and contractions from the base are coupled to the tunable material of the laser, thus varying the wavelength of the output light from the laser.

Abstract: This invention relates to opto-electronic systems using semiconductor lasers driven by optical phase-locked loops that control the laser's optical phase and frequency. Feedback control provides a means for precise, wideband control of optical frequency and phase, augmented further by four wave mixing stages and digitally stitched independent optical waveforms for enhanced tunability.