568results about "Laser output parameters control" patented technology

The invention relates to the technical field of laser temperature control, in particular to a temperature control method and system for a multi-environment VCSEL laser, and the method comprises the steps: collecting the temperature of the VCSEL laser at each moment, and the current of a thermoelectric refrigerating unit used for carrying out the temperature control of the VCSEL laser at each moment; determining the temperature fast adjustment intensity and the temperature oscillation characteristic value of the VCSEL laser at each temperature control moment; obtaining a steady state adjustment value of the VCSEL at each temperature control moment; determining the magnetic field interference suppression intensity of the VCSEL laser at each temperature control moment; and correcting a first threshold value and a second threshold value of the integral separation PID control algorithm, determining a switching coefficient of an integral item in the integral separation PID control algorithm, and performing temperature control on the VCSEL at each temperature control moment. Therefore, the temperature control precision of the VCSEL laser is improved.

The invention relates to the technical field of laser control, in particular to a light spot consistency control method and system for DFB lasers, and the method comprises the steps: obtaining the current and temperature of each DFB laser at each moment in each control period; calculating the burr saliency, the temperature rise drift coefficient, the temperature drop drift coefficient and the heat source interference value of each DFB laser in each control period; and determining expansion and contraction factors of a positive universe and a negative universe in the fuzzy control algorithm, and controlling the temperature of the DFB laser in real time so as to control the light spot consistency of the DFB laser. According to the method and the device, by selecting the proper telescopic factor and dynamically adjusting the discourse domain range of the fuzzy control algorithm, the response speed of temperature control of the DFB laser is improved, the temperature of the DFB laser is controlled more accurately, and light spot consistency control is realized.

The invention provides a patterned photonic crystal laser and a preparation method thereof, the laser comprises a substrate, and a first mask layer, a photonic crystal layer and a second mask layer which are sequentially deposited on the substrate, a light emitting area is etched in the central area of the second mask layer, and transparent conductive layers are deposited on the surface of the second mask layer and the light emitting area; a p-annular electrode is arranged on the surface of the transparent conductive layer on the second mask layer, and an n-annular electrode is arranged below the substrate; the photonic crystal layer is composed of a nanorod array and a polymer filled in gaps of nanorods; holes distributed in a patterned array are etched in the surface of the first mask layer, and nanorods are epitaxially grown in hole areas; the nanorod is formed by sequentially depositing a substrate contact layer, a first waveguide layer, a multi-quantum well layer, a second waveguide layer, a coating layer and a component gradient layer. According to the invention, through collaborative design optimization of all the layers, emission of laser with specific wavelength and preparation of a laser emitting laser with single longitudinal mode, narrow linewidth and stable wavelength are realized.

The invention discloses an on-chip time-frequency transmission system and method based on an octave optical comb and an electro-optical modulation optical comb, and the method comprises the steps: constructing a chip-based optical reference cavity through the technologies of vacuum optical cement, photoresist backflow and the like, and achieving an on-chip ultra-stable laser through a phase modulator and a reflection separation optical path; an on-chip laser source pumping micro-ring resonant cavity is utilized to generate an octave optical frequency comb, frequency multiplication is carried out on the on-chip laser source pumping micro-ring resonant cavity and an additional laser source to realize detection and locking of carrier envelope offset frequency (fceo), frequency beating is carried out on the on-chip laser source pumping micro-ring resonant cavity and the on-chip ultra-stable laser device to realize frequency beating (fbeam) locking, and the laser source is utilized to generate an electro-optical modulation optical frequency comb through a circulating phase modulator to realize frequency beating and locking of the on-chip ultra-stable laser device. And the optical time frequency is locked with the locked octave optical comb, is sent to a far end after polarization control and light amplification, and simultaneously receives an electro-optical modulation optical comb at the far end and performs linear light sampling, so that the transmission of the optical time frequency is realized. The optical fiber or space optical link time-frequency transmission device can realize optical fiber or space optical link time-frequency transmission, and has the advantages of low overall noise, high transmission precision, compact structure, small size, low power consumption and the like.

The invention provides a topological polygonal laser. According to the device, a topological non-trivial domain formed by two-dimensional gyromagnetic photonic crystals is combined with a trivial domain, and an out-of-plane magnetic field externally applied to a sublattice A is started to open an energy band gap, so that a multi-position angular state is realized. The two-dimensional gyromagnetic photonic crystal opens or closes an out-of-plane magnetic field externally applied to the sub-lattice A so as to realize opening and closing of the angular state of the topological angular state laser. The topological multi-angular-state laser is realized by taking the two-dimensional gyromagnetic photonic crystal as a platform, and the topological multi-angular-state laser has the advantages that switching of angular states can be realized without changing the structure, and the laser is topologically protected and has topological robustness.

A self-calibrating driver circuit (100, 300, 400, 500, 700) for a laser diode is disclosed. The circuit comprises a configurable current source (105, 305, 405, 505), a current mirror (115, 315, 415) configured to mirror a current from the configurable current source to a first transistor (120, 320, 420, 520, 720) and to a second transistor (125, 325, 425, 725), and a control circuit (140, 340, 440). The control circuit is configured to monitor a current through the first transistor at a first time, and to configure the current source based on the current through the first transistor to provide a desired current to the second transistor for driving the laser diode at a subsequent second time. A radiation-emitting device comprising one or more of the self-calibrating driver circuits and at least one radiation-emitting element is also disclosed.

The invention relates to the technical field of semiconductor lasers, in particular to a semiconductor laser with an adjustable time domain. According to the time-domain-adjustable semiconductor laser, a mutual injection coupling region and a gain region are arranged on a semiconductor laser chip, the mutual injection coupling region comprises multiple sections of interval units, and the ratio of the length of a saturable absorber region to the length of the gain region in a resonant cavity is controlled by adjusting the absorption / gain characteristics of the interval units. And a plurality of pulse generation mechanisms are switched to adjust the pulse width. On the premise that the structural complexity of the semiconductor laser is reduced, large-range adjustment of laser pulses can be achieved.

The invention discloses an automatic wavelength tuning method and system for a tunable laser based on particle swarm optimization, and is applied to the technical field of wavelength tuning of semiconductor tunable lasers. According to the method, a particle swarm optimization (PSO) algorithm is taken as a core, multi-target iterative search optimization is carried out on initial current-wavelength data, and in a tuning initialization stage, a system firstly carries out coarse scanning on three paths of current of a left reflecting grating region, a right reflecting grating region and a phase modulation region of a sampling grating distributed Bragg reflection laser; manual intervention is not needed, the system can complete efficient configuration screening in a given target wavelength range, the intelligent level of the tuning system is remarkably improved, good automation capacity and expansibility are achieved, scanning of a large number of invalid data and tedious operation procedures in the traditional tuning process are avoided, and the tuning efficiency is improved. And meanwhile, a high-quality current-wavelength lookup table can be quickly constructed, and the method has wide engineering application prospects in optical communication, sensing and other scenes.

A semiconductor laser (1) comprising a semiconductor body (2) with an active region (20) for generating radiation (8) and an optical interaction structure (3) with structural elements (30) is specified, wherein at least some of the structural elements (30) are arranged at different nominal center distances (35) to each other such that, during operation of the semiconductor laser (1) at a given operating point, local temperature differences in the optical interaction structure (3) reduce differences between the optical path lengths (39) that are assigned to the nominal center distances (35) of these structural elements (30). Furthermore, a method for manufacturing a semiconductor laser (1) is described.

The invention relates to the technical field of laser, in particular to a high-signal-to-noise-ratio modulation transfer spectrum frequency stabilization light path system. The system comprises a laser, an optical isolator, a first half-wave plate, a first polarization splitting prism, an optical fiber coupler, a second half-wave plate, a second polarization splitting prism, a first reflecting mirror, an electro-optical modulator, a second reflecting mirror and a third polarization splitting prism, wherein the first half-wave plate is used for adjusting the power of frequency stabilization light; the second half-wave plate is used for adjusting the power ratio of pump light to probe light; a first quarter-wave plate, a second quarter-wave plate, an atomic gas chamber and a photoelectric detector; after the output of the laser is isolated by the optical isolator, the first half-wave plate and the first polarization splitting prism are matched to adjust the frequency stabilization total beam power to about 5mW; the pump light is modulated by the electro-optical modulator, the probe light and the pump light reversely interact in the atomic gas chamber in an anti-phase circular polarization state, and the signal-to-noise ratio of a modulation transfer signal and the stability of a frequency stabilization system are remarkably improved.

The utility model provides a laser control device and wafer detection equipment. The laser control device comprises a laser, incident laser is emitted to a to-be-detected workpiece along an incident light path, and the incident laser forms reflected laser on the to-be-detected workpiece along a reflected light path; the light on-off element is arranged on the incident light path and used for controlling on-off of the incident laser; and the detection element is arranged on the reflected light path, is linked with the light on-off element and is used for detecting the reflected laser so as to enable the light on-off element to act. The laser control device comprises a laser device, a light on-off element and a detection element, reflected laser is detected through the detection element, on-off of an incident light path is controlled through the light on-off element, when the incident laser exceeds a working area, the incident laser can be shielded, propagation of the incident laser is blocked, potential safety hazards are eradicated, propagation of the reflected laser can be blocked, and the laser control efficiency is improved. Potential safety hazards of laser reflection are eliminated, and stability of laser output by the laser can be ensured.

This specification discloses a converter element and light emitting devices including the converter element. The converter element is monolithic with at least two layers, where one layer is more porous than the other layer. The converter element may be integrated with a reflector layer, such as by metallization. The layer of the converter structure that is denser and having a smoother surface may be the one that is metallized, while the more porous layer is closer to the laser. The porosity enhances light extraction while the smoother surface decreases a loss of reflectivity at the reflector-phosphor interface. The converter element may be used in a laser based light emitting device.

The invention belongs to the technical field of single-photon emitters, and relates to a radiation-enhanced single-photon emitter and a preparation method thereof. The radiation-enhanced single-photon emitter comprises an hBN thin layer and an emitter; the emitter is disposed over the hBN thin layer, and the emitter is located within a range of 10 nm over the surface of the hBN thin layer. By using the hyperbolic dispersion characteristic of the hBN thin layer, the enhancement of the Purcell and the enhancement of the photon coupling output power can be realized in a broadband range. The single-photon emitter solves the problems that in an existing single-photon emitter, the photon Pelsel effect is enhanced, and the photon coupling output efficiency is low. Therefore, the application range of the material in photonics and quantum optics is expanded. Compared with an existing single-photon emitter, the single-photon emitter is simple in structure, does not need a complex manufacturing process, and reduces the manufacturing cost.

The invention discloses an on-chip integrated high-power U-band multi-wavelength high-speed laser chip, which relates to the technical field of chip processing, and specifically comprises a P-Si substrate, an epitaxial transition buffer layer, a buffer layer structure, a laser gain region, a waveguide structure, a grating structure region and a ridge waveguide structure. Multi-wavelength high-speed laser is realized on a single chip, beam combination and amplification are realized, different inclined waveguides are adopted to correspond to different grating periods and light emitting wavelengths, multiple target wavelengths can be realized on the single chip through calculation, the laser can simultaneously output four wavelengths of 1621nm, 1641nm, 1661nm and 1681nm by reasonably setting the inclination angles of the ridge waveguides, and the performance of the laser can realize 100G long-distance transmission. A traditional discrete optical device is replaced; the epitaxial P-type substrate and the coplanar electrode are adopted to effectively reduce the series resistance and the heating power consumption of the device, and the multi-path combined high-speed laser is further amplified through the SOA.

The invention relates to the technical field of lasers, in particular to a narrow-linewidth frequency conversion laser which comprises a DFB laser, a first end of the DFB laser is used for outputting initial fundamental frequency light; the lithium niobate outer cavity comprises a spot size converter, a transmission waveguide provided with a phase shift part, a first multi-mode interference coupler, upper and lower speech channel micro-rings, a second multi-mode interference coupler and a periodically poled waveguide which are connected in sequence, and the upper and lower speech channel micro-rings and a Bragg grating of the DFB laser form a resonant cavity; the upper and lower speech channel micro-rings reflect a part of the received light back to the DFB laser to realize self-injection locking and output the other part of the received light to the second multimode interference coupler, the fundamental frequency light passes through the periodically polarized waveguide to realize frequency conversion, and the output end of the periodically polarized waveguide outputs frequency-doubled light; the lithium niobate outer cavity further comprises two comb-shaped electrodes which are symmetrically arranged on the two sides of the periodically poled waveguide. The performance of the narrow-linewidth frequency conversion laser can be improved at least.

A lithium niobate (LN) external cavity includes a Vernier mirror structure which includes two or more microresonators where: one or more or all of the Vernier microresonators are tuned by the electro-optic Pockels effect of LN, with tuning electrodes integrated with the resonators, and one of the Vernier microresonators could be tuned by the thermo-optic effect, with a local heater integrated with the resonator. One or more or all of the Vernier microresonators include a section or the whole resonator that is periodically poled to achieve quasi-phase matching for nonlinear frequency conversion directly inside the laser cavity. The lithium niobate (LN) external cavity also includes a phase shifter whose phase is tuned by the electro-optic Pockels effect of LN. A Sagnac loop mirror is placed at the end of the device to function as the output end mirror of the laser cavity.

The invention discloses a novel laser mode hopping compensation method. The method comprises the following steps that S1, a constraint bent groove for limiting a steel ball to move under KHz-level vibration is designed; s2, detecting a mode hopping phenomenon and parameters in laser output; s3, outputting a round-trip optical path adjustment amount and a curved groove Y-axis sinkage amount based on the mode hopping parameters obtained in the S2; s4, the corresponding position of the constraint bent groove designed in the S1 is polished and optimized based on the adjustment amount obtained in the S3; and S5, iteratively executing compensation until the laser output has no mode hopping. The invention is characterized by providing a novel mode-hopping compensation external cavity semiconductor laser system and a compensation method which are especially suitable for a TDLAS-WMS technology and can accurately sense the type and concentration of gas to be detected.

A semiconductor laser chip (1) comprising a semiconductor body with a sequence of semiconductor layers (2) having an active region (20) for generating radiation is specified, wherein the semiconductor body has a resonator region (3) with the active region (20) and a diode region (4) spaced apart from the resonator region (3), wherein the active region (20) of the resonator region (3) and the diode region (4) are connected antiparallel to each other with respect to their forward direction. Furthermore, a semiconductor laser arrangement (10) with a semiconductor laser chip (1) is specified.

A light emitting device includes: a light emitting unit that includes plural light emitting elements; a transfer unit that transfers a signal for setting a light emitting element to turn into an on state among the plural light emitting elements; and a low-pass filter provided between a reference potential terminal of the transfer unit and an external reference potential.

A frequency sweep control method and apparatus are provided. The method includes: outputting a first optical signal of a first laser unit, where a first frequency sweep range of the first optical signal is determined based on a first reference light emitting frequency and a first frequency variation upper limit; and switching to output a second optical signal of a second laser unit when a first frequency variation of the first optical signal is greater than or equal to a first threshold, where a second frequency sweep range of the second optical signal is determined based on a second reference light emitting frequency and a second frequency variation upper limit, and the first threshold is less than the first frequency variation upper limit.

The invention relates to a semiconductor external cavity frequency doubling green laser and a preparation method, and belongs to the technical field of semiconductor lasers. On the basis of a conventional 1064nm semiconductor laser, laser is directly irradiated on a frequency doubling crystal, and meanwhile, a resonant cavity is formed by coating a cavity surface of the semiconductor laser and an output end of the frequency doubling crystal, so that a structure of a gain medium in a laser for obtaining green light in an original pumping mode is canceled, the complexity and the cost of the laser are greatly reduced, and the laser is more compact and more compact. And the batch condition is realized. And meanwhile, by adjusting the wavelength of the semiconductor laser and matching with the frequency doubling crystal, laser output with the wavelength of 510-540 nm can be realized, and the cost of the laser with the green light wave band can be effectively reduced.

In the field of ultrastable laser technology, tuning an ultrastable laser maintains its performance indicators without increasing additional lock noise and out-of-loop drift. [Solution] One acoustic-optic modulator and one electro-optic modulator are introduced separately, and the laser device, frequency shift unit, PDH frequency stabilization control unit, and ultra-stable cavity are integrated. [Effects] By changing the frequency of the acousto-optic modulator, high-precision tuning of the ultra-stable laser can be achieved. By changing the frequency of the electro-optic modulator, wide-range tuning of the ultra-stable laser can be achieved, enabling wide-range, high-precision, and dead-zone-free frequency tuning.

There is provided an external cavity laser, including: a photonic integrated platform including a gain chip providing a gain medium and at least one reflector chip, the photonic integrated platform including first and second functional layers made of different materials; a resonant cavity optically coupled to the gain medium and including a first and a second micro-ring resonators (MRR) in a Vernier configuration, the first MRR and second MRR extending within respective ones of the first and second functional layers made of different materials and having corresponding group indices, the first and second MRRs having different radii selected in view of said corresponding group indices; and a tuning mechanism for tuning a spectral response of at least one of the first and second MRR.

The present invention concerns a tunable Dense Wavelength Division Multiplex (DWDM) intra cavity laser device having a first optical wave guide having a first optical grating section, a second optical wave guide having a second optical grating section, an active gain section spatially separated from the second optical grating section and a phase section, and a DWDM-filter having an intra-cavity ring resonator located between the first optical wave guide and the second optical wave guide for coupling optical waves between the first and second optical wave guides. The tunable laser device is tunable in a discrete manner depending on a length of the ring resonator that is selected such that the free spectral range of the ring resonator matches a predetermined fixed wavelength spacing grid.

The application discloses a phase-sensitive pre-amplification method based on an electro-absorption modulated laser, and is applied to a star-ground laser communication system receiving end. A distributed feedback laser in the electro-absorption modulated laser amplifies weak pump light after long distance transmission, and generates idler light under the nonlinear effect of a laser cavity; an electro-absorption modulator in the electro-absorption modulated laser detects phase error information between signal light, pump light and idler light, and constructs an optical injection phase-locked loop through a feedback loop, so that stable control of the three-wave phase relationship is realized. Under the phase stability condition, the output light of the electro-absorption modulated laser is fed into a later-stage nonlinear medium to complete phase-sensitive pre-amplification. The phase-sensitive pre-amplification method based on the electro-absorption modulated laser has the advantages of simple structure and easy integration, can realize pump light amplification, idler light generation and phase error suppression under the condition of weak pump light, and effectively improves the receiving sensitivity performance of the star-ground laser communication system.

The invention particularly relates to an optical time-frequency high-isolation distribution device and method based on a microarray laser beam splitting lens. The device comprises a laser driving current source, a time-frequency signal source, a laser, a laser beam splitting array system, a photoelectric detection system and a conditioning and purifying circuit. The method comprises the following steps: adopting a direct-current signal as a laser driving current, and adopting a time-frequency signal source to generate a time-frequency signal with frequency f as a modulation signal; modulating laser output by a laser device by using the modulation signal, and loading the modulation signal to the laser; the modulated laser beam realizes temperature-insensitive beam splitting through the laser beam splitting array system; and the split laser beams are respectively detected by a photoelectric detection system, and direct current removal, filtering, amplification and output are carried out by adopting a conditioning and purifying circuit. According to the invention, by adopting an electric-optical-electric conversion mode, low additional phase noise and high isolation time frequency signal distribution can be realized.

An optical device includes a generator, a light emitter, a modulator, an optical amplifier, a current source, a storage, and a controller. The generator generates an electric signal of a multilevel amplitude modulation method. The light emitter emits laser light. The modulator modulates the laser light using the electric signal and outputs an optical signal. The optical amplifier optically amplifies the modulated optical signal according to a drive current. The current source adjusts the drive current to be supplied to the optical amplifier. The storage previously stores an information with respect to input-output characteristics of the optical signal in the optical amplifier relative to drive current value of the drive current. The controller acquires, from the storage, the input-output characteristics corresponding to the drive current value of the drive current supplied to the optical amplifier and controls the electric signal based on the acquired input-output characteristics.

This invention discloses a Littrow-type cavity length-compensated mode-hopping-free continuously tunable semiconductor laser, comprising a laser diode (1), a collimating lens (2), and a diffraction grating (3). Mode-hopping-free continuous tunability is achieved through a micro-elastic material base (4). The micro-elastic material base (4) is hollowed out to create a movable block (401) that can be driven by a piezoelectric ceramic (5), an isosceles triangular groove (404), and a pair of waist arms (406), enabling micro-displacement and micro-angle changes in the waist arms (406), thereby achieving continuous tunability of the output laser. This invention achieves mode-hopping-free continuous tunability of the laser output through an innovative combination of a special mechanical structure and the frequency selection characteristics of the grating. The structure is compact and highly stable, ultimately resulting in a mode-hopping-free continuously tunable external cavity semiconductor laser that meets the requirements of high-end precision measurement.

The invention discloses a photonic crystal surface emitting laser based on electro-optical effect modulation and an emission angle and wavelength regulation and control method thereof, and belongs to the field of laser devices. The photonic crystal surface emitting laser comprises a substrate layer, an isolation layer and an active LiNbO3 layer; the isolation layer is a SiO2 isolation layer or an air isolation layer, and the air isolation layer is formed by etching the SiO2 isolation layer through a SiO2 etching agent; the active LiNbO3 layer is made of erbium-doped LiNbO3 or ytterbium-doped LiNbO3, and periodic holes are etched in the surface of the active LiNbO3 layer to form the photonic crystal layer. The photonic crystal surface emitting laser is prepared by using the active electro-optical effect material, the electro-optical effect material is combined with the photonic crystal surface emitting laser, and the emission angle and the emission wavelength are regulated and controlled through the electro-optical effect of LiNbO3 and the diffraction effect of the photonic crystal.

Method for characterizing a batch of gain chips, each having a first reflective face and a second transparent face, the method comprising, for each gain chip: positioning the gain chip (99) with the second face facing towards a reflective diffraction grating (6); supplying the gain chip (99) with a plurality of first and second values of supply current so that the gain chip (99) emits a respective first light beam (60) for each first value of supply current and a respective second light beam (60') for each second value of supply current; making impinge each first light beam (60) on the reflective diffraction grating (6) in a first angular position so as to generate a respective first zero-order diffracted beam (61) and a respective first first-order diffracted beam (62) entering the gain chip (99), and each second light beam (60') on the reflective diffraction grating (6) in a second angular position so as to generate a respective second zero-order diffracted beam (63) and a respective second first-order diffracted beam (64) not entering the gain chip (99); measuring a respective first value of optical power of each first zero-order diffracted beam (61), and a respective second value of optical power of each second zero-order diffracted beam (63); associating each first value of optical power with the respective first value of supply current, and each second value of optical power with the respective second value of supply current; as a function of pairs of first values of supply current and of optical power and as a function of a first predetermined mathematical correlation, calculating a respective differential quantum efficiency, and, as a function of pairs of second values of supply current and of optical power and as a function of a second predetermined mathematical correlation, calculating a respective modal gain coefficient and a respective carrier density at transparency; verifying that the respective differential quantum efficiency, the respective modal gain coefficient, and the respective carrier density at transparency satisfy a respective predetermined selection criterion.