Abstract: An OPO is disclosed capable of rapid frequency tuning by non-mechanical means. The OPO includes a resonant cavity including one or more non-linear crystals in an optical path thereof. A pump laser pulse is transmitted into the resonant cavity simultaneously with a seed beam having a desired wavelength. The output beam from the resonant cavity has the same center wavelength as the seed beam. The wavelength of the seed beam may be modulated at a frequency larger than the pulse rate of the pump laser or larger than the inverse of the pulse duration. The OPO disclosed may be used to perform DIAL analysis wherein intra-pulse modulation of an output beam is used to obtain measurements of absorption at multiple frequencies for each pulse of a pump beam.

Abstract: A filtered laser array assembly generally includes an array of laser emitters coupled between external modulators and an arrayed waveguide grating (AWG). Each of the laser emitters emits light across a plurality of wavelengths including, for example, channel wavelengths in an optical communication system. The AWG filters the emitted light from each of the laser emitters at different channel wavelengths associated with each of the laser emitters. Lasing cavities are formed between each of the laser emitters and a back reflector coupled to an output of the AWG such that laser output from the laser emitters is provided at the respective channel wavelengths of the reflected, filtered light. The external modulators enable high speed modulation of the laser output. The modulated laser output may then be optically multiplexed to produce an aggregate optical signal including multiple channel wavelengths.

Abstract: Semiconductor light-emitting devices; methods of forming semi-conductor light emitting devices, and methods of operating semi-conductor light emitting devices are provided. A semiconductor light-emitting device includes a first laser section monolithically integrated with a second laser section on a common substrate. Each laser section has a phase section, a gain section and at least one distributed Bragg reflector (DBR) structure. The first laser section and the second laser section are optically coupled to permit optical feedback therebetween. Each phase section is configured to independently tune a respective one of the first laser section and second laser section relative to each other.

Abstract: A laser pulse synthesis system is provided. A further aspect of the present system uses a phase-only modulator to measure ultrashort laser pulses. An additional aspect achieves interferences between split subpulses even though the subpulses have different frequencies. Yet another aspect of a laser system employs multi-comb phase shaping of a laser pulse. In another aspect, a laser system includes pulse characterization and arbitrary or variable waveform generation through spectral phase comb shaping.

Abstract: Disclosed are systems and methods for using a semiconductor optical amplifier (SOA) as an optical modulator for pulsed signals. In accordance with the principles of the invention, the SOA can be biased with a negative voltage to suppress transmission and improve modulator extinction and biased with a positive pulsed signal with sufficient amplitude to forward bias the amplifier (SOA), both transmitting the carrier and increasing its amplitude by means of a gain provided by the SOA under forward biased conditions. In addition, the forward bias voltage may be selected to compensate for losses within the SOA.

Abstract: A laser processing machine includes a plurality of collimating lenses to convert a laser beam from a laser oscillator, which have been emerged from a point of emergence of a transmission optical fiber, into parallel rays of light, a condensing lens to condense the laser beam and then radiate it onto a work, and a nozzle positioned on one side of the work remote from the condensing lens. The distance from the point of emergence to the tip of the nozzle remains unchangeable. The collimating lenses are spaced from each other in a direction parallel to an optical axis. A switching device switches the position of each of the collimating lenses in the orthogonal direction so that the center of one of the collimating lenses may be aligned with a center of the laser beam. The collimating lenses have respective focal lengths that are different from each other.

Abstract: The present invention relates to a higher-order dispersion compensation device (210), the device being adapted to cooperate with a pair of optical components (P1, P2), e.g. a pair of prisms, being arranged to compensate first-order dispersion by separating different wavelengths spatially. The compensation device (210) has the form of a phase plate, wherein the phase change for each wavelength is adjusted by designing the height (h) at the corresponding position (x) of the plate so as to substantially compensate for higher-order dispersion. The invention is advantageous for obtaining a higher-order dispersion compensation device which is relatively simple to construct and use making it a quite cost-effective device. The invention also relates to a corresponding optical system and method for compensating dispersion where this is important, e.g. in a multiple-photon imaging system.

Abstract: A laser processing system quickly and flexibly modifies a processing beam to determine and implement an improved or optimum beam profile for a particular application (or a subset of the application). The system reduces the sensitivity of beam shaping subsystems to variations in the laser processing system, including those due to manufacturing tolerances, thermal drift, variations in component performance, and other sources of system variation. Certain embodiments also manipulate lower quality laser beams (higher M2 values) to provide acceptable shaped beam profiles.

Abstract: Disclosed is a method for driving a wavelength-swept light source that includes an optical resonator in which an optical gain medium for emitting light, a wavelength selection element for selecting a wavelength of light emitted from the optical resonator, and an optical intensity modulation element for modulating intensity of light within the optical resonator are arranged and that is configured to sweep the wavelength of the emitted light. The method includes driving the optical intensity modulation element and the wavelength selection element in synchronization with each other to keep an instantaneous spectral width of the emitted lights constant.

Abstract: A laser system capable of phase and/or amplitude manipulation of the output pulses is provided. In another aspect, a laser system includes a self-referenced pulse characterization method. A further aspect uses spectral amplitude modulation to isolate spectral bands by scanning one or more transmission slits or openings, and measuring and/or calculating the first derivative of a phase (group delay) across an entire spectrum. A single-beam pulse shaper-based technique for spectrometer-free measurement and compensation of laser pulse phase distortions is also provided in an additional aspect.

Abstract: Embodiments of the present disclosure provide optical connection techniques and configurations. In one embodiment, an opto-electronic assembly includes a first semiconductor die including a light source to generate light, and a first mode expander structure comprising a first optical material disposed on a surface of the first semiconductor die, the first optical material being optically transparent at a wavelength of the light, and a second semiconductor die including a second mode expander structure comprising a second optical material disposed on a surface of the second semiconductor die, the second material being optically transparent at the wavelength of the light, wherein the second optical material is evanescently coupled with the first optical material to receive the light from the first optical material. Other embodiments may be described and/or claimed.

Abstract: A coherent light source apparatus comprises a first optical system, which has a first light emission region formed by a coherent light source, and which projects light from the first light emission region to form a second light emission region, a light deflection unit which deflects light flux in connection with formation of the second light emission region; a second optical system, which forms a third light emission region in response to the light flux which has been deflected by the light deflection unit, a light mixing unit for mixing a component of an incident light angle and that of a position thereof, and a light deflection unit drive circuit for receiving a periodic optical deflection synchronization signal, thereby driving the light deflection unit, wherein the light deflection unit operates to continuously change a direction in which the light flux is deflected while synchronizing with the optical deflection synchronization signal.

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 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.

Abstract: A laser apparatus includes an external cavity laser (ECL) where the optical signal is modulated by an electrical modulation signal for modulating in frequency the laser output signal. The modulation in frequency produces a modulation of intensity (power) of the laser output signal, also denoted amplitude modulation (AM). A method of controlling the AM amplitude of a signal emitted by an ECL includes a gain medium, a phase element with variable transmissivity induced by the modulation, and a spectrally selective optical filter that selects and keeps the AM amplitude below a certain desired value or minimizes such value. A control method and a laser apparatus are also described in which the reduction of the AM component of the output power is achieved by acting on the gain of the gain medium of the ECL.

Abstract: A laser system can include a laser and a laser output modulator to modulate the output of the laser.

Abstract: Techniques and devices for providing optical locking of optical resonators and lasers.

Abstract: A device for amplifying a laser beam is provided. The device includes at least one amplifier chamber in which a laser-active material is provided, at least one transmitting optical member delimiting the amplifier chamber and being arranged at a tilt angle, ?, with respect to a plane oriented perpendicularly with respect to an optical axis of the laser beam, and at least one detection unit. The laser beam is reflected by the transmitting optical member into a back reflected laser beam, and the detection unit is arranged such that it detects the back reflected laser beam.

Abstract: An integrated optical modulator and laser device includes a laser section, a modulator section for modulating the intensity of a laser beam produced by the laser section, and a separation section located between the laser section and the modulator section. The laser section includes a first anode electrode and a first cathode electrode. The modulator section includes a second anode electrode and a second cathode electrode. A lower cladding layer is integral to the laser section, the modulator section, and the separation section and the width of the lower cladding layer is narrowest in the separation section.

Abstract: A system includes a modulatable source and matched modal filter. The modulatable source is associated with a plurality of source modes to provide a generated signal. The matched modal filter is coupled to the modulatable source to receive the generated signal. Filter modes are to match the source modes. The matched modal filter is coupleable to a link fiber to provide a signal to the link fiber. The filter modes are to match a subset of link fiber modes to couple the plurality of filter modes to the link fiber.

Abstract: Provided is a wavelength-tunable external cavity laser module. The wavelength-tunable external cavity laser module includes: a gain medium generating light; an optical waveguide combined with the gain medium and including a Bragg grating and a thin film heater adjusting a temperature of the Bragg grating; and a high frequency transmission medium delivering a high frequency signal to the gain medium, wherein the high frequency transmission medium controls an operating speed of the light.

Abstract: Technology for detecting an optical data signal carried in a combined optical signal that comprises a carrier optical signal modulated by the optical data signal and also comprises ASE noise. The proposed optical data detector/receiver is provided with an SHG device adapted to generate a second harmonic optical signal of the carrier optical signal modulated by the data signal. In the signal, generated by the SHG, the ASE noise will be essentially reduced.

Abstract: Devices and techniques for frequency conversion of radio frequency (RF) or microwave signals based on photonic processing.

Abstract: The present invention provides a system and method for creating a coherent optical comb comprising a plurality of lasers, each laser providing an optical output channel; means for combining each optical channel output; a modulator for modulating the combined optical channel outputs, to provide a modulated signal; means for feeding back said modulated signal to said plurality of lasers, such that each laser output channel is phase and/or frequency locked with respect to at least one other of said plurality of lasers. A discrete optical comb is obtained without the need for excessively high power laser outputs and only employs a single (optional) wavelength locker for all channels.

Abstract: Apparatus, systems, and methods having a frequency comb of large spacing can be used in a variety of applications. In various embodiments, a frequency comb is generated from a slave laser by injecting an optical output from a drive laser into the slave laser. One or more parameters of the drive laser and/or the slave laser can be adjusted such that a frequency comb can be generated at a multiple of the repetition rate of the drive laser. Additional apparatus, systems, and methods are disclosed.

Abstract: A laser device including a plurality of oscillating means for oscillating a plurality of laser lights being continuous lights and having frequencies different from each other, respectively, multiplexing means for multiplexing, after amplifying or without amplifying, the respective laser lights oscillated from the respective oscillating means at a predetermined position to generate a multiplexed light, and phase control means for controlling the phase of each of the laser lights so that a peak in output of the multiplexed light repeatedly appears at predetermined time intervals at the predetermined position (so that the same pulse temporal waveform repeatedly appears at predetermined time intervals).

Abstract: An algorithm to drive a semiconductor laser diode (LD) is disclosed. The algorithm assumes that the modulation current to keep the extinction ratio in constant has temperature dependence represented by an exponential function under the average output power of the LD is kept constant by an auto-power-control (APC). When a tracking error exists and the approximation by an exponential function is turned out in failure, the algorithm adds a correction to the exponential function determined by a difference between a practically measured modulation current and another modulation current calculated from a value determined for a bared LD.

Abstract: A photonic integrated circuit (PIC) having multiple Mach-Zehnder (MZ) modulators with different lengths is provided. The modulator lengths are selected to provide optimal performance for each optical path provided on the PIC.

Abstract: The present invention relates to laser ablation microlithography. In particular, we disclose a new SLM design and patterning method that uses multiple mirrors per pixel to concentrate energy to an energy density that facilitates laser ablation, while keeping the energy density on the SLM mirror surface at a level that does not damage the mirrors. Multiple micro-mirrors can be reset at a very high frequency, far beyond current DMD devices.

Abstract: A laser apparatus may include: a master oscillator configured to output a pulsed laser beam at a repetition rate, the master oscillator including at least one semiconductor laser apparatus; at least one amplifier configured to amplify the pulsed laser beam from the master oscillator, the at least one amplifier being configured to include at least one gain bandwidth; and a controller for controlling a parameter affecting an output wavelength of the pulsed laser beam from the master oscillator such that a wavelength chirping range of the pulsed laser beam from the master oscillator overlaps at least a part of the at least one gain bandwidth.

Abstract: An optical semiconductor device in which light having a wavelength of 1.25 ?m or greater is waveguided, includes: a first waveguide of embedded type that includes a semiconductor and is lattice-matched with InP, the first waveguide having a region having a first constant width equal to or greater than 1.50 ?m and a first region narrower than the region; and a second waveguide of embedded type that includes another semiconductor having a refractive index different from that of the first waveguide, the second waveguide having a region having a second constant width smaller than 1.50 ?m and a second region wider than said region. The first waveguide and the second waveguide are joined at an intermediate waveguide portion. The intermediate waveguide portion includes the first region and the second region and a joining plane on which the first region and the second region are joined. The joining plane has a width equal to or smaller than 1.35 ?m.

Abstract: A non-linear FM pulse compression system includes a non-linear FM transmitter adapted to receive an input signal and transmit an output signal. The non-linear FM transmitter is adapted to modulate the frequency of the output signal by at least one of the following: increasing the frequency of the output signal as a logarithmic function of the frequency of samples in the input signal; modulating the frequency of the output signal in inversely proportional relationship to the frequency of samples in the input signal; and modulating the frequency of the output signal according to a random permutation of the frequency of the input signal. At least one antenna interfaces with the non-linear FM transmitter. A non-linear FM receiver interfacing with the at least one antenna. The non-linear FM receiver is adapted to auto-correlate the output signal with a return signal.

Abstract: A light source wavelength modulator includes a substrate made of a material with a high light transmittance and a thermal conduction effect, a wavelength modulation layer formed on the substrate and made of a wavelength modulation material, and patternized or multilayered, and further having a spacer between the wavelength modulation layer and its corresponding light source for achieving the best light source wavelength modulation, such that a portion of light spectrum of an original solar light or LED having no response or poor response to the light receiver is converted into a range of the best application efficiency for improving the utility efficiency of the light source. The white light emitted from the LED is gone through a wavelength modulation to enhance the light emitting color rendering, conversion efficiency and using life.

Abstract: Provided is a laser module. The laser module comprises: a substrate; an gain unit oscillating a laser light on the substrate; an external resonance reflecting unit total-reflecting the laser light at an external of the substrate adjacent to one side of the gain unit; and an inner resonance reflecting unit reflecting the laser light to the external resonance reflecting unit at the substrate between the modulating unit and gain unit and outputting the laser light to the modulating unit.

Abstract: A laser device of an equal-energy pulse synchronous with motion includes: a resonant cavity, outputting a plurality of pulses with stable pulse-width and energy; a beam switch modulator, selectively enabling one of the pulses to pass; a beam energy modulator, adjusting the energy of the pulse according to a power feedback signal; an optical power sensor, sensing the energy and the pulse-width of the pulse; a motion controller, providing processing motion information; an optical feedback controller, outputting the power feedback signal to the beam energy modulator according to the energy of the pulse and the processing motion information; a trigger controller, measuring a time difference between time when the pulse is triggered and time when the optical power sensor detects the pulse, and correcting a turn-on time point of the beam switch modulator. The processing quality is therefore stabilized, and the device is applicable to various laser industrial processes.

Abstract: The present invention relates to a laser apparatus with a structure for realizing a fast response in carrying out a start and an end of output of pulsed laser light while effectively suppressing damage to an optical amplifying medium. The laser apparatus is provided with a seed light source, an optical amplification section, a pulse modulator, a pump power controller, and a main controller. The pulse modulator receives an output start instruction and an output end instruction fed from the main controller and controls a start and an end of output of seed light from the seed light source. The pump power controller receives a pump trigger signal fed from the main controller and increases or decreases a power of pump light supplied to the amplification section.

Abstract: A circuit assembly controlling an optical system to generate optical pulses is provided. The optical system includes a seed light source optically coupled to an amplitude modulator. The circuit assembly includes a control circuit which generates a pulsed seed drive signal for driving the seed laser source, as well as logic signals defining successions of ON and OFF states and having a predetermined relative timing relationship. One or more of the logic signals is delayed by a corresponding programmable delay line to adjust the relative timing relationship between the logic signals. A logic gating module combines the logic signals according to one or more logical rule, thereby providing a modulator drive signal. Using this circuit assembly, the optical system outputs an optical pulse at each ON state of the modulator drive signal synchronized with the passage of one of the seed optical pulses through the amplitude modulator.

Abstract: Two pulsed lasers (14) or sets of lasers propagate beams of pulses (20) having orthogonally related polarization states. A beam combiner (24) combines the orthogonal beams to form a combined beam propagating along a common beam path (16) to intersect an optical modulator (30) that selectively changes the polarization state of selected pulses of either beam to provide a composite beam (18) including similarly polarized pulses from the orthogonal beams. The composite polarized beam has a composite average power and a composite repetition rate that are greater than those provided by either laser. The optical modulator can also selectively control the polarization states of pulses from either laser to pass through or be blocked by a downstream polarizer (32). Additional modulators may facilitate pulse shaping of the pulses. The system is scalable by addition of sets of single lasers or pairs of lasers with beam combiners and modulators.

Abstract: A pulse width modulation method for controlling the output power of a pulsed gas discharge laser powered by a pulsed RF power supply comprises delivering a train of digital pulses to the RF power supply. Each pulse in the train has an incrementally variable duration. The power supply is arranged to deliver a train of RF pulses corresponding in number and duration to the train of digital pulses received. The average power in the RF-pulse train can be varied by incrementally varying the duration of one or more of the digital pulses in the digital pulse train. The train of RF pulses is used to power a gas discharge laser. The gas discharge laser outputs a pulse train corresponding to the RF pulse train.

Abstract: A method to control an LD (laser diode) is disclosed. The method compares the operating temperature of the LD with a transition temperature. When the former temperature exceeds the latter, the modulation current is set based on the bias current, which is independently determined by the APC loop. On the other hand, the operating temperature is less than the transition temperature; the modulation current is determined by the operating temperature.

Abstract: There is provided an output coupler modulated laser. The laser includes an optical resonator for light to circulate within, a gain medium housed within the optical resonator and a pump. An output coupler included in the optical resonator is responsive to a control signal to generate a modulated optical signal at a laser output port, and a complementary signal at a through port to retain circulating light within the optical resonator. The output coupler and the pump are jointly controllable to maintain the power level of the circulating light substantially at a selected, steady state level, and to decouple the modulation response of the laser from the intrinsic response of the circulating light due to interaction with the gain medium. The output coupler is configurable for simple amplitude modulation, Phase-Shift Keying (PSK), Quadrature Amplitude Modulation (QAM), and is suitable for use with high-finesse, micron or millimeter scale resonators.

Abstract: Whispering gallery mode resonator based devices as photonic RF or microwave receivers.

Abstract: The present invention discloses a method and device for the bias control of an MZ modulator. The method comprises: during startup of an MZ modulator, inputting a linearly changing bias control voltage to the bias electrode of the MZ modulator and obtaining the output optical power of the MZ modulator so as to determine a bias control voltage corresponding to a preset operating point; then enabling a communication electrical signal to be input to the radio frequency electrode of the MZ modulator, carrying out an amplitude modulation on the communication electrical signal by a low-frequency sinusoidal pilot signal, and inputting the determined bias control voltage to the bias electrode simultaneously; and sampling the output optical signals of the MZ modulator, comparing the sampled optical signal with the pilot signal, and adjusting the bias control voltage input to the bias electrode according to the result of the comparison.

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 provides, in at least one embodiment, a scheme which is effective in suppressing detrimental coherence effects such as random backscatter. In a fiber laser having a master oscillator power amplifier design, inserting a decorrelator in between the master oscillator and a first power amplifier or inserting a decorrelator in between the first power amplifier and a second power amplifier to reduce random backscatter, which allows for much more energy to be stored and higher gain without the risk of catastrophic optical damage, thus increasing the peak power that can be delivered as useful laser power. Backscattering can be further reduced by having the master oscillator depolarized, injection locked, and spectrally broadened to reduce the coherence length of the master oscillator.

Abstract: A control system and apparatus for use with an ultra-fast laser is provided. In another aspect of the present invention, the apparatus includes a laser, pulse shaper, detection device and control system. A multiphoton intrapulse interference method is used to characterize the spectral phase of laser pulses and to compensate any distortions in an additional aspect of the present invention. In another aspect of the present invention, a system employs multiphoton intrapulse interference phase scan. Furthermore, another aspect of the present invention locates a pulse shaper and/or MIIPS unit between a laser oscillator and an output of a laser amplifier.

Abstract: The invention relates to a beat signal generating device for use in a Terahertz system, comprising a first monomode laser for generating radiation of a first wavelength; a second monomode laser for generating radiation of a second wavelength different from the first wavelength; a first and a second output port; a phase modulating unit for modifying both the phase of radiation generated by the first laser and the phase of radiation generated the second laser, wherein the beat signal generating device is configured in such a way that the radiation generated by the first laser is transmitted through the second laser and superposed with the radiation generated by the second laser at the second output port, and the radiation generated by the second laser is transmitted through the first laser and superposed with the radiation generated by the first laser at the first output port, such that a first beat signal will be emitted at the first output port and a second beat signal will be emitted at the second output

Abstract: An optical module providing higher reliability during high-speed light modulation and a lower bit error rate when built into a transmitter (transceiver). An optical module contains a taper mirror for surface emission of output light, an optical modulator device, and an optical modulation drive circuit, and the optical modulator device and the optical modulation drive circuit are mounted at positions so as to enclose the taper mirror.

Abstract: This disclosure is directed to widen an adjustable range of the spectral linewidth of laser light output from a laser apparatus. This laser apparatus may include: (1) an excitation source configured to excite a laser medium in a laser gain space, (2) an optical resonator including an output coupler arranged on one side of an optical path through the laser gain space and a wavelength dispersion element arranged on the other side of the optical path through the laser gain space, and (3) a switching mechanism configured to switch a beam-width magnification or reduction factor by placing or removing at least one beam-width change optical system for expanding or reducing a beam width in or from an optical path between the laser gain space and the wavelength dispersion element or by inverting orientation of the at least one beam-width change optical system in the optical path.

Abstract: A lock in pinned photodiode photodetector includes a plurality of output ports which are sequentially enabled. Each time when the output port is enabled is considered to be a different bin of time. A specified pattern is sent, and the output bins are investigated to look for that pattern. The time when the pattern is received indicates the time of flight A CMOS active pixel image sensor includes a plurality of pinned photodiode photodetectors that use a common output transistor. In one configuration, the charge from two or more pinned photodiodes may be binned together and applied to the gate of an output transistor.