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2861 results about "Gain" patented technology

In laser physics, gain or amplification is a process where the medium transfers part of its energy to the emitted electromagnetic radiation, resulting in an increase in optical power. This is the basic principle of all lasers. Quantitatively, gain is a measure of the ability of a laser medium to increase optical power.

Monitoring image processing method and system for high-precision target tracking

The invention discloses a monitoring image processing method and system for high-precision target tracking, and belongs to the technical field of monitoring processing, and the method specifically comprises the steps: collecting polarization data of incident light in a monitoring scene, and generating a physical attribute signature of a light source; carrying out space-time clustering analysis on pixel points of which the variable quantity exceeds an environment illumination baseline in the monitoring scene to form a physical boundary of an illumination mutation region; obtaining motion trail data of the target vehicle, and generating a motion trail space area of the target vehicle; marking an overlapping region of the physical boundary of the illumination abrupt change region and the motion trail space region as a dynamic interference source influence region; if the predicted position of the target vehicle is located in the dynamic interference source influence area, calling an exposure control parameter and a gain control parameter corresponding to the physical attribute signature, calculating a focusing control parameter according to the scene depth of the predicted position, and loading the focusing control parameter to a sensor control unit; according to the method, the problem of target key frame loss caused by AE / AF delay under dynamic illumination is effectively solved.
Owner:ZHONGSHAN PUBLIC SECURITY BUREAU SANXIANG BRANCH

Temperature regulation and control device and method for semiconductor laser

The invention relates to the technical field of semiconductor lasers, in particular to a temperature regulation and control device and method for a semiconductor laser, and the method comprises the steps: obtaining different types of monitoring curves, and analyzing the complex change characteristics of operation temperature and operation power according to the monitoring curves, so as to determine a heat accumulation effect index; determining the degree of efficiency loss caused by the heat accumulation effect by analyzing the correlation among the operation temperature change, the operation power change and the threshold current change and combining the heat accumulation effect index; then determining a temperature regulation and control demand coefficient by analyzing the temperature feedback control precision condition and the thermal dynamic characteristic of the semiconductor laser and combining the efficiency loss degree; and finally, a default proportional gain value in the PID control module is adjusted by using the temperature regulation and control demand coefficient to obtain an adjusted proportional gain value so as to carry out temperature regulation and control on the semiconductor laser, which is beneficial for the temperature regulation and control device to respond to the change of the working environment of the laser in time.
Owner:SHENZHEN ZHONGKE OPTICAL SEMICON TECH CO LTD

VGA-based 5G miniature optical transceiver module self-calibration method

The invention discloses a VGA (Video Graphics Array)-based 5G miniature optical transceiver module self-calibration method, which belongs to the technical field of optical transceiver module self-calibration, and comprises the following steps: S1, establishing a self-calibrated benchmark reference value through an initialization module and collecting environment parameters and benchmark optical parameters; s2, dynamically collecting and receiving optical power and environment change data, and judging whether deviation exceeds a threshold value or not to trigger model retraining by collecting actual operation data of environment parameters and driving parameters and combining a neural network model prediction target value; integration of a new data set and re-fitting of a non-linear relation enable the model to continuously adapt to the influence of long-term factors; key parameters such as a gain coefficient or a temperature compensation curve of a proportional-integral-differential control algorithm are dynamically corrected, long-term precision and reliability of a self-calibration system are guaranteed, and the problem of calibration failure caused by failure of a static model is avoided.
Owner:ZHENJIANG XIPUXIN PHOTOELECTRIC TECH CO LTD

Method and device for measuring three-dimensional size of large-size part based on machine vision

The invention relates to the technical field of large-size part three-dimensional measurement, and discloses a large-size part three-dimensional size measurement method and device based on machine vision, and the method comprises the steps: obtaining a material reflection characteristic reference data set and original point cloud data; according to the reference data set, laser power and gain are adjusted in a self-adaptive mode, and optimized scanning parameters are obtained; and performing denoising, feature extraction, region segmentation and plane fitting according to the optimized parameters and the original point cloud to obtain a high-precision geometric dimensioning result. According to the invention, high-precision, high-stability and high-efficiency three-dimensional size measurement can be realized on a large-size part made of a complex material and having a curved surface, and the three-dimensional size measurement method is obviously superior to a traditional scheme.
Owner:WUXI TUCHUANG INTELLIGENT TECH CO LTD

Quasi-continuous thulium-doped fiber laser capable of synchronously suppressing relaxation oscillation and self-pulse

The invention provides a quasi-continuous thulium-doped fiber laser capable of synchronously suppressing relaxation oscillation and self-pulse, relates to the technical field of fiber laser, and is used for simultaneously realizing suppression of a self-pulse effect and a relaxation oscillation peak. Comprising a continuous driving module, a pulse driving module, a semiconductor laser pumping source, a high-reflectivity fiber bragg grating, a low-reflectivity fiber bragg grating, a beam combiner, a thulium-doped gain fiber, a passive fiber, a cladding pumping stripper and a laser output port, the continuous pump light and the pulse pump light are respectively driven by the continuous driving module and the pulse driving module to output continuous pump light and pulse pump light; the high-reflectivity fiber bragg grating and the low-reflectivity fiber bragg grating form a resonant cavity structure, the thulium-doped gain fiber serves as a gain medium of the thulium-doped fiber laser and absorbs pump light to generate population inversion, laser oscillation is formed by combining the resonant cavity of the laser, relaxation oscillation suppression is achieved, and meanwhile longitudinal mode distribution of the laser is effectively disrupted.
Owner:SHENZHEN TECH UNIV

Vehicle-mounted laser radar point cloud real-time target detection method and system

The invention relates to the technical field of vehicle-mounted radar detection, and discloses a vehicle-mounted laser radar point cloud real-time target detection method and system, and the method comprises the steps: collecting an image sequence through a vehicle-mounted polarization camera, obtaining a light entropy gradient spectrum of a tunnel entrance and exit region, recognizing a gradient abrupt change point, and predicting a light entropy abrupt change interval; generating a dual-channel gain weight matrix to receive an original point cloud; then, a dispersion area is identified, dispersion point clouds are marked, a space-time motion equation is constructed to predict ossification point clouds to obtain complete point clouds, finally, artifacts in an artifact vortex area are identified and removed, and a final detection result is obtained; according to the method, the problems of laser radar point cloud local saturation distortion and vehicle false detection caused by sudden change of strong light at the tunnel entrance and exit are effectively solved, and safe and reliable operation of applications such as automatic driving is guaranteed.
Owner:NANJING ANTONGJIE TECH IND CO LTD

Unmanned aerial vehicle obstacle avoidance method fusing vision and laser in weak light environment

The invention relates to the technical field of unmanned aerial vehicle autonomous obstacle avoidance, and discloses an unmanned aerial vehicle obstacle avoidance method fusing vision and laser in a weak light environment, and the method comprises the following steps: obtaining a visible light image, depth information, sparse laser point cloud and real-time illumination intensity; processing the image and the point cloud data, and fusing to generate the position, size and category of the obstacle; based on the obstacle information, constructing a risk assessment model, and assessing a flight situation risk level; according to the risk level, generating an obstacle avoidance behavior sequence including speed, height and scanning adjustment; based on the obstacle avoidance behavior sequence, the flight path of the unmanned aerial vehicle is updated and flight is controlled; during flight, the visual depth and the laser point cloud are utilized to iterate and self-calibrate the external parameters of the sensor online. According to the method, the exposure time and the gain are adaptively adjusted, the sparse point cloud is acquired in combination with the laser radar, and deep processing and fusion are performed on the image and the point cloud data in the multi-scale cross-modal fusion network, so that the perception performance of a single sensor in a weak light environment is effectively overcome.
Owner:BEIJING SUSHI INFORMATION TECH CO LTD

Path planning method and device based on photon pulse reinforcement learning network

The invention discloses a path planning method and device based on a photon pulse reinforcement learning network, and relates to the field of photon pulse reinforcement learning networks, and the method comprises the steps: adjusting the phase of each phase shifter in an explicit MZI network according to a multi-level pulse neural network, and configuring a weight matrix; carrying out pulse signal loading on the light source by using a light modulator to obtain an input signal; obtaining a plurality of linear calculation results by using the weight matrix and the input signal through an interference effect and a coupling effect; inputting the plurality of linear calculation results into the DFB-SA laser, and obtaining a nonlinear activation result by adjusting the injection current of a gain region of the laser and the reverse bias voltage of a saturation region of the laser; and taking the nonlinear activation result as a new input signal, and returning to the step of obtaining a plurality of linear calculation results by using the weight matrix and the input signal until calculation of all levels in the pulse neural network is completed, so that path planning which is high in speed, low in power consumption and easy to configure is realized.
Owner:XIDIAN UNIV

Data acquisition and analysis system for laser interference measurement and method thereof

The invention relates to a data acquisition and analysis system and method for laser interference measurement, and aims to solve the problem of limited measurement precision caused by asynchronous signal acquisition, imperfect environmental interference compensation and algorithm errors of the existing system. The system comprises a photoelectric conversion unit, a signal conditioning unit, a high-speed synchronous acquisition unit, a real-time processing unit and an error compensation module. The photoelectric conversion unit adopts a four-quadrant PIN photodiode array to receive interference light signals and convert the interference light signals into analog electric signals; the signal conditioning unit performs gain adjustment and bandwidth limitation on the signal; the high-speed synchronous acquisition unit realizes femtosecond-level synchronous acquisition of signals; the real-time processing unit performs phase solution and eliminates harmonic errors based on an improved arc tangent algorithm; and the error compensation module fuses temperature sensor data and accelerometer data to realize thermal drift and vibration compensation.
Owner:张翼

Preparation method of low-power-consumption photonic integrated device and corresponding device of low-power-consumption photonic integrated device

The invention discloses a low-power-consumption photonic integrated device preparation method and a corresponding device, and relates to the technical field of semiconductor optoelectronic integrated devices.The device comprises a substrate, a cantilever beam type grating layer, two gain layers, two modulator layers, a wrapping layer and an electric contact layer, the two gain layers and the two modulator layers are symmetrically distributed, and the wrapping layer and the electric contact layer form a shallow ridge waveguide structure. The two symmetrically-distributed gain layers and the middle cantilever beam type grating layer jointly form a double-end resonant cavity structure, the structure shares a unified grating and a thermal tuning platform to achieve continuous, synchronous and high-precision control over cavity mode wavelengths, and balanced modulation and phase synchronization of double-end output are achieved in cooperation with the symmetrically-integrated high-speed modulator layers on the two sides. According to the technical scheme, the gain layer, the grating layer and the modulator layer are symmetrically integrated on the same substrate, the alignment error of a multi-cavity structure is reduced, synchronous scanning, low drift and strong anti-interference high-quality laser output can be obtained, meanwhile, efficient thermal tuning is conducted through the cantilever beam type grating layer, and power consumption is remarkably reduced.
Owner:WUHAN GUOKE OPTICAL SEMICON TECH CO LTD

External cavity tunable laser linewidth compression system for realizing wavelength phase locking based on mutual injection of gain chips

The invention discloses an external cavity tunable laser linewidth compression system for realizing wavelength phase locking based on mutual injection of gain chips. The external cavity tunable laser linewidth compression system comprises a red light semiconductor laser main gain chip, a first collimation optical system, a blazed grating, a tuning rotating mirror, a reflector, a power supply driving system and a double-path feedback amplification system, the double-path feedback amplification system comprises a first secondary gain chip, a second secondary gain chip, a second collimation optical system, a third collimation optical system and a polarization-free beam splitter prism; and the red light semiconductor laser main gain chip, the first secondary gain chip and the second secondary gain chip are all connected with the power supply driving system. Therefore, the technical problems of low output infrared light power, poor stability and narrow mode-hopping-free tuning range in the prior art are solved, and high-power, narrow-linewidth, high-stability and large-range mode-hopping-free continuous tuning red light output can be realized.
Owner:HUAZHONG UNIV OF SCI & TECH

Low-divergence-angle narrow-linewidth high-power semiconductor laser

The invention discloses a low-divergence-angle narrow-linewidth high-power semiconductor laser. Relates to the technical field of semiconductor lasers, in particular to a low-divergence-angle narrow-linewidth high-power semiconductor laser. According to the invention, the parabolic waveguide structure is etched in the light field expansion area, and the metal reflector is introduced to realize a novel light field expansion and metal reflector integrated structure, and the transverse divergence angle of a laser mode is reduced through the expansion structure at the tail end of the waveguide. The laser comprises a laser gain area, a light field expansion area and a spectrum purification area at the tail of the light field expansion area. The laser gain region, the light field expansion region and the spectrum purification region at the tail part of the light field expansion region are made of the same laser epitaxial material in the longitudinal direction, the laser gain region is adjacent to the light field expansion region along the horizontal light emitting direction, and the light field expansion region is adjacent to the spectrum purification region at the tail part of the light field expansion region along the horizontal light emitting direction; the longitudinal direction is the direction from the substrate to the contact layer.
Owner:CHANGCHUN UNIV OF SCI & TECH +1

Chip-integrated mode-locked lasers based on thin-film nonlinear waveguides

PendingUS20250364772A1Laser detailsLaser optical resonator constructionSignal waveNonlinear waveguide
A chip-scale mode-locked laser including a cavity including a gain medium for amplifying signal electromagnetic radiation (signal) through stimulated emission, the signal comprising a signal wavelength; and a passive or active mode-locking device to enforce pulse formation in the laser. The mode-locking device includes a thin-film waveguide having a thickness on the order of the signal wavelength so as to confine and guide the signal along the thin-film waveguide, and a material comprising a second-order nonlinear susceptibility to enable active or passive mode-locking of the signal. The mode-locking device leads to generation of pulses of the signal outputted from the mode-locked laser.
Owner:CALIFORNIA INST OF TECH

Coherent light high-speed transmission signal processing method based on depth joint compensation

The invention belongs to the technical field of signal processing, and particularly relates to a coherent light high-speed transmission signal processing method based on deep joint compensation, which comprises the following steps of: performing fine frequency offset and inter-carrier interference joint preprocessing on a coherent light receiving sampling sequence; obtaining a pre-processing output sequence and at least one estimation parameter derived from fine frequency offset and inter-carrier interference combined pre-processing; inputting the preprocessing output sequence into a diffusion type score guide joint compensation network module to obtain a deep joint compensation sequence; performing online judgment and decoding on the deep joint compensation sequence, and adaptively updating internal parameters of the diffusion type score guide joint compensation network module when a preset adaptive updating condition is met; according to the invention, the symbol residual error can be obviously reduced, the forward error correction gain can be improved, and the stability and robustness of the system under high-order modulation, high symbol rate and long-distance link scenes can be enhanced.
Owner:SHENZHEN BIYANG OPTICAL COMM TECH CO LTD

External synchronous picosecond-level jitter macro-energy picosecond pulse laser output method and device

PendingCN120709822ALaser detailsSemiconductor amplifier structurePicosecond pulsed laserHigh energy
The invention discloses a method and a device for outputting large-energy picosecond pulse laser with external synchronization picosecond-level jitter. The device comprises a high-precision time sequence controller, a semiconductor picosecond pulse seed source, an optical isolator and a high-gain and high-stability regenerative amplifier. The semiconductor picosecond pulse seed source outputs low-energy picosecond-level (10-12J, pJ) and low-jitter picosecond-level (10-12s, ps) picosecond pulse seeds under the trigger of a time sequence controller of a high-precision external clock, the picosecond pulse seeds enter the high-gain high-stability regenerative amplifier through the optical isolator, and the high-gain high-stability regenerative amplifier outputs high-energy picosecond-level (10-12s, ps) picosecond pulse seeds under the control and adjustment of the high-precision time sequence controller. The picosecond pulse seed is locked to be regenerated and amplified in the regenerative amplifier, and the energy of the picosecond pulse seed with low energy and low jitter at a picofocus (pJ) level is amplified to uJ-mJ (10 <-6 > J-10 <-3 > J), so that low jitter and large energy output of laser pulses and trigger signals are realized, and application development of high-precision laser ranging, laser communication, time-frequency transmission and the like is effectively promoted.
Owner:SHANGHAI ASTRONOMICAL OBSERVATORY CHINESE ACAD OF SCI

High-power picosecond pulse train laser with programmable sub-pulse energy and method

The invention discloses a high-power picosecond pulse train laser with programmable sub-pulse energy and a method, and relates to the related technical field of lasers, the high-power picosecond pulse train laser comprises a mode-locked fiber laser, an acousto-optic modulator and a solid amplification chain which are sequentially arranged along an optical transmission path; the mode-locked fiber laser generates a mode-locked picosecond pulse sequence; the acousto-optic modulator performs pulse selection and pulse string grouping on the mode-locked picosecond pulse sequence, and performs pre-programming shaping on sub-pulse energy in a pulse string according to set intensity distribution to generate a pre-shaped pulse string; the solid amplification chain comprises at least one stage of solid amplifier, and the solid amplifier comprises a dichroscope, a laser gain crystal, a coupling optical assembly and an LD pumping source; and the dichroscope is used for focusing the pre-shaped pulse string amplified at the previous stage and the LD pump light transmitted by the coupling optical assembly into the laser gain crystal. Independent programmable regulation and control of the energy of each sub-pulse in the pulse string are realized, and the energy distribution of each sub-pulse in the pulse string can be flexibly adjusted.
Owner:SHANDONG UNIV

Multi-mode reconfigurable diamond solar-blind ultraviolet photoelectric transistor and preparation method thereof

The invention discloses a multi-mode reconfigurable diamond solar-blind ultraviolet photoelectric transistor and a preparation method thereof, and aims to solve the problem of separation of sensing, storage and calculation frameworks of an existing artificial vision system. According to the diamond solar blind ultraviolet photoelectric transistor, a terminal is arranged on the surface of a diamond substrate, a first metal film layer is deposited on the upper surface of the diamond substrate to serve as a first contact electrode, the first contact electrode is Schottky contact, and a second contact electrode is a metal probe. The second contact electrode is in needle point contact with the upper surface of the diamond substrate, a second metal film layer is deposited on the lower surface of the diamond substrate to serve as a third contact electrode, and the third contact electrode is Schottky contact. According to the reconfigurable diamond solar blind ultraviolet photoelectric transistor, different functions of an avalanche detector, an optical memory, visual synapse and the like are integrated in one device, and large gain rising of the diamond detector and multi-mode intelligent sensing of a single device are achieved.
Owner:HARBIN INST OF TECH +2

Multifunctional comprehensive scintillation crystal and semiconductor material energy spectrum test system

The invention relates to the field of crystal detection, and discloses a multifunctional comprehensive scintillation crystal and semiconductor material energy spectrum test system, which comprises a crystal adaptation module for judging the type and size of a placed crystal through an optical identification and parameter matching mechanism, and a signal acquisition module for amplifying, filtering and digitally processing an acquired signal, the signal correction module is used for correcting waveform distortion and baseline drift through a dynamic gain adjustment algorithm of a low-noise pre-amplifier and a multi-channel pulse analyzer; the data analysis module is used for generating an energy spectrum curve according to input signals and calculating energy resolution, counting rate, light attenuation time or carrier mobility, and the environment calibration module is used for dynamically evaluating shading degree, environment light, temperature and electromagnetic interference through an optical sensor and a temperature and humidity detector in the camera obscura and outputting updated calibration parameters. The method has the advantages of improving the detection efficiency, precision and consistency.
Owner:BEIJING MICROARIS PHOTOELECTRIC TECH CO LTD

Range adaptive detection method and system based on light source and gain cooperative adjustment

The invention belongs to the technical field of environmental monitoring, and particularly relates to a range adaptive detection method and system based on light source and gain cooperative adjustment. The method comprises the following steps: setting a detection system to be in a small-range working state; signal acquisition is carried out, and a signal value after analog-to-digital conversion is obtained; judging whether the signal value reaches a saturation threshold value or not; determining a combination of new light source intensity and new sensor gain according to a pre-stored calibration parameter table; adjusting the light source intensity of the detection system to Inew, and adjusting the sensor gain to Gnew; after adjustment, new signal acquisition and conversion are carried out to obtain a new signal value, a pre-stored calibration parameter table is inquired to obtain a corresponding compensation coefficient based on the currently used combination of Inew and Gnew, and a compensated real concentration value is calculated and output. According to the invention, the core contradiction that the measurement precision and the measuring range are difficult to consider in a wide concentration range in the traditional fixed-measuring-range detection technology is fundamentally solved.
Owner:TIANJIN TONGYANG TECH DEV

High-Power Optical Gain Waveguides

High-power, integrated optical amplifiers are described in which gain waveguides of the amplifiers are designed to improve power performance by reducing power saturation effects in the amplifier. The gain waveguides can change, in at least one aspect, along the length of the gain waveguide to reduce gain saturation. Multi-mode optical beams and / or multi-stage amplification can also be employed to reduce gain saturation.
Owner:BEACON PHOTONICS INC

Polariton device, polariton system, method of manufacturing polariton device, and method of controlling polariton device

Provided are a polariton device, a polariton system, a method of manufacturing the polariton device, and a method of controlling the polariton device. The polariton device includes a cavity including a gain layer including a ferroic material that undergoes a phase transition into an asymmetrical crystal structure in response to an external stimulus, an upper reflective layer formed on top of the cavity, a lower reflective layer formed below the cavity, and a Rabi frequency controller configured to control a Rabi frequency of the polariton device by providing a stimulus to the gain layer.
Owner:DAEGU GYEONGBUK INSTITUTE OF SCIENCE AND TECHNOLOGY

Signal processing method and system for long-distance follow-up laser seeker

The invention provides a signal processing method and system for a long-distance follow-up laser seeker, and belongs to the technical field of signal processing. Target surface center coordinates, a light spot image sequence and a synchronous echo pulse waveform sequence of the seeker are obtained; the speckle energy entropy and the centroid drift distance are obtained by calculating the information entropy and the centroid displacement of the target light spot image, and the pulse width parameter is extracted from the echo waveform. And constructing the three parameters into a laser feature vector, and inputting the laser feature vector into a pre-trained reflecting surface classification model so as to identify the surface material type of a laser irradiation point in real time. And determining a group of optimal follow-up control gain sets from the material gain mapping relation according to the surface material type, and dynamically reconstructing a follow-up control loop by using the optimal follow-up control gain sets. And the sight angle error of the light spot mass center and the target center is calculated, and the adjusted control loop is used for calculating the error to generate an accurate driving instruction signal, so that the tracking stability and the tracking precision of the target are improved.
Owner:BEIJING GK XINYI TECH

Heterogeneous Photonic Circuits

Heterogeneous photonic circuits comprise a gain section optically coupled to a photonics section. The gain section can include at least one gain waveguide which can be formed from a III-V semiconductor material to provide optical gain. The gain waveguide can be coupled to optical components in the photonics section to form an integrated pump module. The photonics section can include a light-generating photonic circuit, which can comprise at least one waveguide doped with a rare-earth ion or transition-metal ion. Output from the integrated pump module and / or the light-generating photonic circuit can be tunable. Tuning can be implemented with feedback control.
Owner:BEACON PHOTONICS INC

Preparation method and structure of photonic integrated device

ActiveCN120742484AOptical waveguide light guideElectro-absorption modulatorGrating
The invention discloses a preparation method and a structure of a photonic integrated device, and the method comprises the steps: sequentially dividing a substrate into a front modulator region, a rear modulator region, a front grating region, a gain region and a rear grating region, and growing a first active layer after manufacturing a selected region epitaxial mask pattern in the gain region, the method comprises the following steps of: growing a first active layer in a front modulator region after mask etching operation, growing a second active layer in a front modulator region after mask etching operation, growing a third active layer in a grating region after mask etching operation, finally performing grating manufacturing, and completing manufacturing of a cladding layer, an electric contact layer, an inverted table shallow ridge waveguide structure, an electric isolation trench and an electrode. According to the method, integration of multiple materials is achieved through one-time selective area epitaxial growth and one-time butt joint growth, the material growth frequency is reduced, and the manufacturing cost is saved; the gain region and the rear modulator region realize forbidden band width offset through selective region epitaxial material growth, and multi-wavelength tuning and efficient modulation are realized through fluorescence wavelength difference design of each region, so that a solution can be provided for integration of a wide-wavelength tunable laser and a double-electro-absorption modulator.
Owner:WUHAN GUOKE OPTICAL SEMICON TECH CO LTD

Active optical resonator for frequency conversion

An optical parametric oscillator and method for generating coherent signal light involve a resonant optical cavity for coherent signal light, and in the cavity a non-parametric gain element for amplifying the coherent signal light to only partially compensate for passive optical roundtrip losses, thereby obtaining lower effective roundtrip losses. A parametric gain element is arranged in the cavity, for converting coherent pump light into coherent signal light through an instantaneous nonlinear optical interaction. The parametric oscillator has means for adjusting an intracavity optical power of the coherent pump light above a threshold value, where the parametric gain is balancing the effective roundtrip losses, thus inducing sustained oscillations of the signal light in the optical cavity. The non-parametric gain element is configured to have a limited non-parametric gain over a gain bandwidth of the parametric gain element, which is less than the passive optical roundtrip losses in the gain bandwidth.
Owner:UNIV LIBRE DE BRUXELLES

Scanning high-resolution double-optical-comb spectrum system based on Raman gain modulation

The invention discloses a scanning high-resolution double-optical-comb spectrum system based on Raman gain modulation. The method is suitable for real-time spectrum detection with a wide spectrum range and high spectral resolution. The system comprises a single-frequency laser and driver, an optical coupler, a mode-locked laser, a rare earth doped amplifier, a wavelength division multiplexer, a Raman gain fiber, a sample to be tested, a photoelectric detector, a data processor and a wavemeter. The single-frequency laser couples part of light to the wavemeter, and the remaining light is divided into two paths to be coupled with the two amplified mode-locked lasers to enter the Raman gain optical fiber for Raman gain modulation and is converted into high-mutual-dryness double optical combs. The double combs pass through a to-be-measured sample in a combined manner, and interference signals are measured by the photoelectric detector and received by the data processor. And meanwhile, the processor sends a tuning signal to the single-frequency laser driver, so that the double combs scan in a wide spectrum range to obtain high-resolution spectrum information. Electrical feedback locking is not needed, and high-precision spectrum acquisition with megahertz resolution in a terahertz range can be completed within a few minutes.
Owner:SHANGHAI INST OF OPTICS & FINE MECHANICS CHINESE ACAD OF SCI

Miniaturized medium-long wave infrared solid-state laser using thulium-doped laser to directly pump ZGP crystal

The invention relates to a miniaturized medium-long wave infrared solid-state laser in which a thulium-doped laser directly pumps a ZGP crystal, the thulium-doped laser takes two laser diodes with the central emission wavelength of 793 nm as pumping sources, two Tm: YAP crystals with the same parameters are cascaded and placed in a U-shaped resonant cavity to serve as laser gain media, and an acousto-optic Q crystal controls intra-cavity loss in the resonant cavity, so that the thulium-doped laser directly pumps the ZGP crystal. Pulse laser with the wavelength of 1.94 m is output; the 1.94 m pulse thulium laser serves as pump light and passes through the ZGP-OPO module, and 2.8 m signal light and 6.2 m idler frequency light are obtained. The Tm laser outputs 1.94 m laser through primary oscillation to directly serve as a pump source, the ZGP-OPO outputs medium-long wave infrared laser in a nonlinear mode, the overall light path structure of the medium-long wave laser is simplified, and the electro-optical conversion efficiency is improved.
Owner:SHANGHAI INST OF OPTICS & FINE MECHANICS CHINESE ACAD OF SCI

Water surface reflected light suppression method and system in laser radar water level measurement

The invention belongs to the technical field of laser radars, and discloses a water surface reflected light suppression method and system in laser radar water level measurement, and the method comprises the steps: employing a multispectral fusion and dynamic polarization modulation technology, precisely filtering the interference of water surface reflected light, matching with a time-frequency domain combined filtering algorithm, and deeply analyzing signal features. An intelligent environment sensing mechanism monitors environment changes in real time, a machine learning model accurately predicts the trend of reflected light, system parameters such as laser transmitting power and receiving end gain are adjusted in advance, measurement errors are reduced, the water level measurement precision of the laser radar is greatly improved, and the water level measurement precision of the laser radar is greatly improved. The system reliability and stability are remarkably enhanced, the scheme is excellent in performance under severe conditions such as strong light by means of the capability of dynamically adapting to complex environment changes, the modular design of the system facilitates integration with an existing laser radar system, expansibility and compatibility are good, and the system can quickly adapt to equipment of different specifications and models.
Owner:YUNNAN TUOMEI DECORATION ENGINEERING CO LTD

Multi-chip vertical external cavity surface emitting laser

The invention relates to the technical field of lasers, in particular to a multi-chip vertical external cavity surface emitting laser which comprises a chip set, a first prism, a second prism and an output coupling mirror which are sequentially arranged along a preset central axis. The chipset comprises N gain chips, and the N gain chips output N sub light beams; the N sub-beams pass through the first prism, the sub-beams emitted from the first prism converge towards a preset central axis, the sub-beams are incident to the second prism before convergence and are combined into a resonant beam through the second prism, the resonant beam resonates in a resonant cavity formed by the output coupling mirror and the chip set, and the output coupling mirror and the chip set form a resonant cavity; the output laser is emitted from the output coupling mirror; wherein N is greater than 1. The invention is beneficial for solving the problems that the power of a single chip is limited, the beam combining efficiency is low, only incoherent beam combining can be realized, and a multi-chip beam combining structure is complex.
Owner:CHANGCHUN INST OF OPTICS FINE MECHANICS & PHYSICS CHINESE ACAD OF SCI

Broadband wide-angle scanning array antenna based on metasurface lens

The invention discloses a broadband wide-angle scanning array antenna based on a metasurface lens, belongs to the technical field of phased-array antennas, solves the problem of how to improve the scanning range and gain of the phased-array antennae, and is characterized in that the metasurface lens with phase gradient is loaded above the phased-array antenna on the basis of not changing the structure of the original phased-array antenna. The beam scanning range of the phased-array antenna is expanded, and the performance such as gain is improved; according to the invention, an original phased-array antenna does not need to be modified and redesigned, additional active devices do not need to be added, new components do not need to be introduced into an original system, the system cost is effectively reduced, the system size is reduced, and the antenna is suitable for scenes, such as unmanned aerial vehicles and low-altitude aircrafts, which have strict requirements on the size and the weight.
Owner:CHINA ELECTRONIC TECH GRP CORP NO 38 RES INST