225 results about "Multi wavelength laser" patented technology

According to the cable end face multi-level defect detection method based on multi-wavelength laser scanning, defect information of different parts of the cable end face can be efficiently and accurately detected by combining laser scanning of different wavelengths, and a more reliable technical guarantee is provided for safe operation of a power system; a cable end face multi-level defect detection method based on multi-wavelength laser scanning comprises the following steps: step 1, scanning a cable end face through a multi-wavelength laser scanning device to obtain original three-dimensional point cloud data of different levels including a metal wire, a sheath, an insulating layer and the like; 2, Gaussian filtering is carried out on the obtained original three-dimensional point cloud data, scanning noise is eliminated, and three-dimensional point cloud data is generated; step 3, extracting multi-scale defect features; and 4, judging the position, the size, the depth, the type and the potential risk level of the defect in combination with the reflection characteristics and the geometric characteristics, and generating a defect assessment report.

The invention discloses an insulator pollution intelligent identification method and system based on a multispectral laser radar, and belongs to the technical field of external insulation state monitoring and intelligent operation and maintenance of a power system, and the method comprises the steps: S1, employing a multi-wavelength laser radar which comprises at least three emission wavebands and comprises 1550 nm to scan an insulator, and selecting at least three wavebands from {355 nm, 405 nm, 532 nm, 905 nm, 1064 nm and 1550 nm}; distance gating is set according to the measuring range, and the width of a time window is 5 ns to 50 ns so as to suppress corona and background interference; through double calibration of an airborne reference sheet and a ground polarization datum plate, fitting is carried out after registration and calibration, angle response correction is carried out on a DPR, and meanwhile, the angle sensitivity of a weight is constrained in complex index solution, so that the relative fluctuation of an SGT under different visual angles is controlled within 3%, and the relative fluctuation of a DPR is controlled within 3%. Therefore, the problem of inconsistent identification results caused by attitude change and incident angle difference is solved.

The invention belongs to the technical field of laser application, and discloses a feedback type multi-wavelength optical fiber laser shaping and amplifying system which comprises a laser light source, an optical fiber frequency doubling device and a laser shaping and amplifying mechanism. The laser shaping and amplifying mechanism comprises a laser shaping and amplifying branch or more than two laser shaping and amplifying branches which are arranged in sequence; the laser shaping and amplifying branch comprises a feedback type laser shaping device and an optical fiber gain amplifying device; the optical fiber frequency doubling device is used for carrying out selective frequency conversion on fundamental frequency laser output by the laser light source; the feedback laser shaping device is used for carrying out waveform shaping on target wavelength laser; and the optical fiber gain amplification device is used for performing gain amplification on the shaped target wavelength laser. The device has the advantages of being simple in structure and high in expansibility, is suitable for being used in an optical fiber laser application system, and is used for modulating laser frequency, improving multi-wavelength laser waveforms and improving multi-wavelength laser output energy.

Provided is a medical skin treatment device including a control unit for controlling the operation of the skin treatment device; a main body which includes a transfer unit and a power supply unit; and a handpiece which is supplied with power from the power supply unit and controlled by the control unit and one side of which is brought into contact with a patient's skin to irradiate same with laser beams. The handpiece includes at least four different laser diodes; the at least four laser diodes radiate laser beams of four different wavelengths and comprise first laser diodes, second laser diodes, third laser diodes, and fourth laser diodes; the number of the first laser diodes is 30 percentage or less of the total number of the laser diodes; and the number of the fourth laser diodes is 25 percentage or greater of the total number of the laser diodes.

The invention relates to the technical field of lasers, in particular to a multi-wavelength laser structure which comprises a heat sink capable of rotating along a rotating shaft, and the rotating shaft is perpendicular to the top face of the heat sink. The wavelengths corresponding to the gain chips in the plurality of gain chips are different, and the plurality of gain chips are annularly arranged on the top surface of the heat sink around the rotating shaft; the output coupling mirror is positioned on one side, far away from the heat sink, of the plurality of gain chips, and the output coupling mirror is matched with the gain chip opposite to the output coupling mirror to form a laser resonant cavity so as to realize laser output; wherein the heat sink rotates along the rotating shaft to switch the gain chips right opposite to the output coupling mirror, when different gain chips are matched with the output coupling mirror, the wavelengths of the lasers output by the multi-wavelength laser structure are different, and the multi-wavelength laser structure at least facilitates the switching of the wavelengths of the output lasers and the simultaneous output of the lasers of multiple wavelengths by adopting a single laser.

The invention relates to the technical field of optoelectronic devices, in particular to a multi-wavelength laser packaging device and detection equipment, and the multi-wavelength laser packaging device comprises a substrate, a box dam and a light-transmitting material which are sequentially arranged from bottom to top; the multi-wavelength laser packaging device further comprises a reflection component and a plurality of laser chips. The center of the reflection component is arranged at the center of the bottom of a cavity formed by the box dam, and the laser chips are symmetrically arranged on the two sides of the reflection component. The plurality of laser chips are used for emitting laser with at least one wavelength to irradiate an incidence point of the reflecting component; and the reflecting component is used for reflecting laser emitted by each laser chip, emitting the laser to the outside through the light-transmitting material, and converging the laser at a preset fixed distance from the chip. Different-wavelength lasers emitted by a plurality of integrated laser chips are converged at a fixed distance through the reflecting component, so that simultaneous detection of multi-wavelength lasers is realized, and portable design is facilitated.

The invention discloses a spaceborne multi-wavelength laser radar detection cloud particle physical property inversion method. The method comprises the following steps: solving the altitude height and the surface height of each point of an echo signal; de-noising the echo signal; correcting the pre-processed signal to obtain an attenuated backscattering signal and identifying a cloud boundary; establishing a molecular transmittance lookup table, and calculating transmittance and atmospheric molecular parameters; the back scattering coefficient of the cloud is obtained through inversion according to the attenuation back scattering signal, the transmittance lookup table, the aerosol and cloud particle transmittance and the atmospheric molecule parameters; the optical thickness, the extinction coefficient and the like of the cloud are calculated by using the attenuation backscattering signal, the cloud particle and atmospheric molecule transmittance and the atmospheric molecule parameters; calculating the depolarization ratio of the cloud; calculating an integral backscattering coefficient and an integral depolarization ratio of the cloud by using the cloud boundary information; and identifying a cloud particle phase state. The method is characterized in that cloud boundary identification is carried out on spaceborne laser radar echo signals, and cloud optical parameters are solved accurately and efficiently.

The invention relates to the technical field of semiconductor lasers, and particularly provides a tunable narrow-linewidth multi-wavelength laser based on injection locking, which comprises a light source, an optical splitter, a coupler, a photoacoustic frequency shifter and a micro-ring, the optical path of each sub-beam is provided with a photoacoustic frequency shifter and a micro-ring, the photoacoustic frequency shifters are responsible for adjusting the frequency of the sub-beams, the micro-rings and a light source form an injection locking relation and compress the line width of the sub-beams, then all the sub-beams are combined through a coupler, and finally power amplification is conducted through a semiconductor optical amplifier. Through the optical splitter, the photoacoustic frequency shifter and the micro-ring, the single light source system outputs equally-spaced multi-wavelength laser, and the defects of a traditional multi-light-source design are overcome.

The invention discloses a multi-wavelength laser based on a vertical gain cavity, and belongs to the field of semiconductor lasers. Comprising a vertical emission array chip and a silicon-based external cavity chip, the vertical emission array chip is mainly characterized in that light is vertical to the surface of the chip and emits light, the vertical emission array chip comprises at least two vertical emission devices serving as an optical vertical gain area, and the silicon-based external cavity chip comprises a coupler, a phase modulation area, a light reflector, a wavelength division multiplexer and an output area. Mode selection is carried out through the light reflector, light feedback of different wavelengths is achieved, a laser resonant cavity is formed by the light reflector and the vertical emission array chip, and work of multiple single wavelengths is achieved; and finally, wave combination is carried out through a wavelength division multiplexer to form the multi-wavelength laser. The device is high in integration level, good in stability, simple in process and low in cost, and the technical effects of ultra-multiple channels, ultra-narrow linewidth, large output optical power and large-area integration can be achieved at the same time.

A multi-wavelength laser radar system for measuring atmospheric carbon dioxide and water vapor concentrations, the system is composed of a multi-wavelength laser transmitting module and a laser radar receiving module. The present invention allows the use of a laser to output three different wavelength pulse lasers in the 1572nm band to independently measure atmospheric carbon dioxide and water vapor concentrations at the same time. The present invention obtains atmospheric carbon dioxide and water vapor concentrations based on a laser integral path differential absorption method.

A photonic integrated circuit device includes a lasing cavity for resonating at a plurality of discrete wavelengths and an optical feedback cavity operably coupled to the lasing cavity via a front surface of the lasing cavity. The optical feedback cavity has a reflective element for reflecting light, at least partially, back into the lasing cavity to form a resonant Fabry-Perot cavity between the front surface and the reflective element. The optical feedback cavity includes a variable phase shifting element adapted for receiving an input signal to control a phase shift of light propagating in the optical feedback cavity. The amount of light entering the lasing cavity from the optical feedback cavity is low enough to avoid dynamic instability of the lasing cavity. The reduction in light is obtained using an attenuator.

The invention provides an intelligent cashmere doping content judgment system utilizing multi-mode Raman spectrum characteristics, and relates to the technical field of intelligent spectrum analysis. The cashmere doping content intelligent judgment system utilizing the multi-mode Raman spectrum characteristics comprises a data acquisition module, a multi-wavelength laser excitation unit is used for carrying out space scanning on a sample, time sequence Raman spectrums under different polarization configurations are synchronously acquired, and the time sequence Raman spectrums are analyzed; multi-dimensional original data including space coordinates, a time sequence, spectral intensity and a polarization state is formed, and an original multi-modal data set is generated. Through multi-wavelength laser space scanning and polarization time sequence synchronous acquisition, a multi-dimensional original data set containing space coordinates, a time sequence, spectral intensity and a polarization state is constructed, the dimension limitation of a traditional spectrum is broken through, and a three-dimensional convolution kernel is adopted to perform synchronous sliding processing in space and spectrum dimensions, so that the spectrum intensity and the polarization state are obtained. And the spatial distribution rule and multi-mode spectrum correlation characteristics of the doped region are directly captured.

The invention belongs to the technical field of laser protective eyeshades, particularly relates to an engineering field self-regulation laser protective eyeshade based on a sensor technology and artificial intelligence, and is used for solving the problems that an existing protective eyeshade solution cannot adapt to a dynamically changing laser environment, color distortion interferes with user vision and the environmental interference is high. According to the invention, by fusing a sensor technology and an adaptive dynamic control algorithm, the color rendition capability and the anti-interference capability of a visible light wave band are remarkably improved while millisecond-level laser threat response is realized, so that the technical bottlenecks of strong visual and environmental interference and the like of traditional protection equipment in engineering field application are solved; the device is especially suitable for complex construction scenes with high-frequency mechanical vibration and multi-wavelength laser cross operation.

The invention provides multi-wavelength laser composite wood layered cutting equipment which comprises a base, a placing plate, a transmission assembly, a cutting mechanism and a clamping mechanism, the placing plate is arranged on the base, a rotating roller of the placing plate is used for bearing wood, a push plate is driven by a second electric telescopic rod to push the wood, and the cutting mechanism is used for cutting the wood. The cutting mechanism is composed of an electric telescopic rod, a guide rail sliding block, a multi-wavelength laser module and the like, three-dimensional space positioning and multi-wavelength switching can be achieved, the clamping mechanism is matched with wood of different specifications through a two-way adjustable L-shaped clamping plate, and through cooperative work of a mechanical positioning system and multi-wavelength laser, the equipment can achieve multi-wavelength cutting according to the material and thickness of the wood. Laser with different wavelengths such as ultraviolet light, green light and infrared light is automatically switched for layered cutting, the problems that traditional cutting is low in precision, serious in carbonization, insufficient in efficiency and the like are solved, high-precision, high-efficiency and low-energy-consumption wood processing is achieved, and the device can be widely applied to furniture manufacturing.

The invention discloses a multi-wavelength laser collimator based on radial shearing. The multi-wavelength laser collimator comprises a near-field reference, a telescope objective combination, a bifocal objective and an image detector which are sequentially arranged along a light path. Aberration-free imaging of near-field light beams is achieved through a bifocal objective lens, and meanwhile far-field pointing is detected through coaxial shearing interference generated by means of amplitude light splitting. A single non-mobile sampling detection light path and a single detection sensor are used to realize simultaneous acquisition of near-field position information and far-field pointing information of a laser beam; the light spot position deviation and the fringe translation amount are analyzed through a computer, and high-precision collimation is achieved through a feedback control system. And the detection of the angle direction of the laser beams with various wavelengths can be realized by using a radial shearing interference technology. The device breaks through the limitation of traditional double-optical-path collimation, has the characteristics of simple structure, strong anti-interference performance, multi-wavelength applicability and the like, remarkably improves the collimation precision, reduces the cost, and has important application value in the field of laser precision collimation.

The invention provides a method and a system for wirelessly monitoring blockage of a filter screen of a dust remover. The method comprises the following steps: irradiating the surface of a filter screen by multi-wavelength laser to collect optical scattering data of particle accumulation, and extracting scattering angle distribution and intensity change characteristics under different wavelengths; collaborative analysis is carried out on a structured sequential sequence of particle accumulation distribution formed by multi-source scattering, a dynamic correlation mode is captured through scattering mode correlation processing, and an abnormal spectrogram fused with multi-wavelength collaboration is constructed; and mapping the data to a filter screen three-dimensional space coordinate to generate particle stacking density three-dimensional distribution data, generating a blockage position and severity level monitoring result according to a density over-threshold value, and pushing the blockage position and severity level monitoring result to a mobile terminal for display. According to the invention, three-dimensional space positioning and real-time grading alarm of the blockage degree of the filter screen are realized, and the maintenance accuracy of the purifier and the user response timeliness are improved.

The invention discloses a multi-wavelength laser, and relates to the technical field of lasers, and the multi-wavelength laser comprises a first output device, a cladding light filter, a first light source assembly, a composite resonant cavity, a second light source assembly and a second output device which are sequentially connected through a central fiber. Wherein the composite resonant cavity is internally provided with a plurality of sub-cavities which are sequentially connected through a central fiber, and the sub-cavities are used for receiving light source light beams emitted by the first light source assembly and / or the second light source assembly and converting the light source light beams into laser beams with corresponding wavelengths; the first output device is used for receiving and emitting the laser beam generated by the composite resonant cavity, and the second output device is used for receiving and emitting the reflected light in the central fiber. According to the technical scheme, stable output of multiple wavelengths is achieved, the nonlinear effect threshold value is increased, and the higher output power level is achieved.

An opto-acoustic metrology device, such as a picosecond laser acoustic metrology device, includes a laser light source that generates pulsed light with a first wavelength and a supercontinuum generator spectrally broadens the pulsed light. A pump arm receives the pulsed light and generates pump pulses to irradiate a target sample to cause transient perturbation in the target sample. A probe arm receives the pulse light and generates probe pulses to irradiate the target sample to produce reflected probe pulses that are modulated based on the transient perturbation in the target sample. The pump pulses and the probe pulses have different wavelengths or the same wavelengths that are selected from the spectrally broadened pulsed light, e.g., using a filter located before the pump and probe arms or within one of the pump or probe arms. A property of the target sample may be determined based on reflected probe pulses.

The invention provides a method for intelligently adjusting laser power of a flow cytometer, which belongs to the technical field of flow cytometers, and comprises the following steps of: establishing a power coupling matrix, and establishing a double-layer game optimization model containing upper-layer laser power stability error minimization and lower-layer laser power interference minimization; a laser power decoupling prediction model based on a Transform architecture is applied to predict and optimize power coupling influence quantity, temperature coefficient parameters are dynamically adjusted to adapt to temperature changes of different lasers, power adjustment increments of the lasers are calculated, and double-layer optimization results are subjected to weighted fusion to obtain an optimal power adjustment strategy. The power value of each laser is adjusted according to the optimal strategy to realize multi-wavelength laser power decoupling control, and the technical problem that the detection precision of the flow cytometer is unstable due to mutual coupling interference of the power of the multi-wavelength lasers is solved.

A narrow-pulse-width multi-wavelength laser based on LED pumping comprises a reflecting mirror, a first LED pumping module, an optical rotation crystal, a second LED pumping module, an acousto-optic Q-switched crystal and an output mirror which are sequentially connected in series. The LED pumping module comprises a laser rod located in the center, a glass sleeve is arranged on the periphery of the laser rod in the length direction, a supporting frame is arranged on the periphery of the glass sleeve, a plurality of sets of water-cooling copper blocks are evenly arranged on the supporting frame, and an LED stacking array is arranged on the side, close to the glass sleeve, of each set of water-cooling copper blocks. Each LED stacking array comprises an LED light bar and a PCB (Printed Circuit Board) for fixing the LED light bar, and the PCB is connected with the water-cooling copper block; cooling water circulation modules are arranged at the two ends of the laser rod in the length direction respectively, and water through holes are formed in the cooling water circulation modules and the water cooling copper blocks respectively. A laser resonant cavity system of the laser takes an LED as a pumping source, combines an acousto-optic Q-switching technology, and simultaneously realizes compression of laser pulse width and multi-wavelength output.

A photonic element includes a bottom cladding, a top cladding and a first waveguide that is located between the bottom and top claddings. A first multi-wavelength grating is optically coupled with the first waveguide. The multi-wavelength grating is characterized by a grating strength that varies along a first axis based on a piecewise mathematical function. The first waveguide and the multi-wavelength grating collectively enable an output having a plurality of wavelengths.

The invention discloses a laser detection system based on traffic overload control equipment and a detection method thereof. Comprising a multi-wavelength laser detection module, a feedback adaptive laser power control module, a data fusion processing module, a vehicle load estimation module and a laser vision auxiliary calibration module. According to the system, through a multi-wavelength laser modulation and feedback control mechanism, accurate detection of the vehicle load under different environmental conditions is realized, and the signal separation degree in a complex traffic flow is remarkably improved. The system is combined with an adaptive weighting algorithm, multi-lane interference can be effectively isolated, the accuracy of single vehicle overload detection is improved, meanwhile, real-time image calibration is conducted on the bottom of a vehicle through a low-cost visual sensor, laser reflection errors are eliminated, and the detection precision of an edge area is ensured. Besides, through multi-dimensional data fusion and dynamic load estimation, overload detection speed and precision are optimized, detection delay caused by traffic jam or errors is reduced, and efficient and safe traffic management is ensured.

The invention discloses a compact power balance multi-wavelength laser device and a manufacturing method thereof. The device comprises a multi-channel DFB laser array, a plurality of second-level SOAs, a third-level Y combiner and a first-level SOA. A grating of the DFB laser array is a plurality of grating units which are periodically and gradually changed in a laser cavity; and equivalent pi phase shifts are introduced among the sections, so that accurate wavelength interval control and stable single-mode output are realized. The device is formed by stacking an n-type InP substrate, a buffer layer, an n-type InAlGaAs lower limiting layer, a multi-quantum well layer, a p-type InGaAsP upper limiting layer, a grating layer, a p-type InP cladding, a p-type InGaAsP transition layer and a p-type InGaAs contact layer. By adjusting the working current of the two-stage SOA and DFB laser devices, multi-wavelength laser light can be output at the same time under a compact structure, and the multi-wavelength laser device has the advantages of being uniform in wavelength interval, balanced in power and high in single-mode stability.

The utility model relates to a gas detection system which comprises a laser emission unit, a reflection unit, a coupling output mirror and a gas detection unit, and the laser emission unit comprises a plurality of multi-wavelength lasers arranged in a linear array; the reflecting unit comprises a first reflecting mirror and a second reflecting mirror which are oppositely arranged; the coupling output mirror and the second reflecting mirror are oppositely arranged; the gas detection unit comprises an incident optical fiber, an absorption gas chamber, an emergent optical fiber and a photoelectric detector, one end of the incident optical fiber is connected to the coupling output mirror, the absorption gas chamber is provided with an incident end and an emergent end, the incident end is connected to the other end of the incident optical fiber, and one end of the emergent optical fiber is connected to the emergent end; the input end of the photoelectric detector is connected to the other end of the emergent optical fiber. Through cooperation of the multiple multi-wavelength lasers, the first reflecting mirror, the second reflecting mirror and the coupling output mirror, multi-wavelength oscillation laser can be output, different light absorption spectrums can be generated, and multi-component gas can be detected.

The invention discloses a method for inverting a cloud condensation nucleus number concentration profile based on a laser radar and a neural network. The method comprises the following steps: collecting multi-wavelength laser radar data including a backscattering coefficient vertical profile, an extinction coefficient vertical profile, a laser radar ratio and a depolarization ratio; the method comprises the following steps: acquiring an atmospheric temperature profile and a water vapor mixing ratio profile which are in time-space synchronization with multi-wavelength laser radar data, performing grid alignment on a vertical height, and constructing a multi-channel input feature set for each preset target supersaturation ratio; and constructing a convolutional neural network profile inversion model, taking the multi-channel input feature set as input and the cloud condensation nucleus number concentration profile data as output, training the model, and obtaining the trained convolutional neural network profile inversion model. According to the method, the limitation of continuous, high-precision and high-temporal-spatial-resolution detection of CCN number concentration vertical distribution is overcome, and key data support is provided for the fields of weather forecast, climate models, artificial influence weather and the like.

A multi-function projector includes a multi-wavelength laser source, a metasurface, and a light sensor. The multi-wavelength laser source is configured to emit a laser beam, wherein a wavelength of the laser beam is capable of being switched to a first wavelength or a second wavelength. The metasurface is disposed on a path of the laser beam and configured to diffract the laser beam onto a projected surface. The metasurface is configured to diffract the laser beam with the first wavelength to form a light pattern on the projected surface, and the metasurface is configured to diffract the laser beam with the second wavelength to form flood illumination on the projected surface. The light sensor is disposed beside the metasurface and configured to sense the projected surface.

The invention provides a system and a method for measuring insertion loss and return loss of a multi-core optical fiber link based on an OFDR (Optical Frequency Domain Reflectometer), and belongs to the field of optical fiber link diagnosis and measurement. The system is composed of a multi-wavelength laser, three wavelength division multiplexers, two couplers, N circulators, a photoelectric detector, a data acquisition card, a to-be-measured link and an upper computer, the multi-wavelength laser outputs laser with N wavelengths, the wavelength division multiplexers multiplex signals and then divide the signals into signal light and reference light through a first coupler, the signal light is used for being output to the to-be-measured link, and the reference light is used for being output to the to-be-measured link. A mixing signal formed by the reflected light of the to-be-measured link and the reference light interferes in the photoelectric detector, a coherent mixing signal containing the insertion loss and return loss information of the to-be-measured link is measured, and the insertion loss and return loss of each node of the to-be-measured link can be calculated by analyzing the coherent mixing signal. By using the OFDR technology, the full-range measurement from the starting point to the ending point of the optical fiber is realized, so that the OFDR can comprehensively diagnose the health state of the optical fiber link.

The complex water environment multi-wavelength laser attenuation simulation system comprises a multi-wavelength laser emission module, a water body environment simulation module, a light splitting module and a power detection module. Seawater characteristics such as temperature, salinity and turbulence intensity of a water body are accurately controlled, parameters such as turbidity of the water body are changed by adding suspended particles such as diatomite and calcium carbonate, and high-precision simulation and measurement of laser attenuation characteristics in different underwater environments are realized by combining a multi-wavelength laser radar technology. According to the multi-wavelength underwater test system, through difference analysis among multiple wavelengths, environment simulation of laser detection capability and substance identification in different water body environments such as turbulent flow and quantitative influence among multi-wavelength laser can be effectively simulated; more comprehensive transmission characteristic experiment test verification and capability simulation under multi-wavelength laser are provided for underwater target identification, marine environment monitoring, resource exploration and other applications, and the multi-wavelength marine detection potential of future laser is expected to be improved.

The invention relates to a system for detecting the concentration of gas in liquid. The system comprises a liquid storage tank, a multi-wavelength laser, an optical fiber laser hydrophone and mobile equipment, the liquid storage tank is provided with a resonant cavity which is used for accommodating a liquid sample; the multi-wavelength laser is arranged opposite to the incident end of the liquid storage tank, and the multi-wavelength laser is used for emitting a laser beam to the liquid storage tank, so that gas in the liquid sample can absorb laser and generate a sound wave signal; the optical fiber laser hydrophone is arranged in the resonant cavity and is used for collecting sound wave signals and converting the sound wave signals into optical signals; the mobile equipment is in communication connection with the fiber laser hydrophone and is used for calculating according to the optical signal to obtain the concentration of the detected gas. Through cooperation of the multi-wavelength laser, the fiber laser hydrophone and the mobile device, degassing treatment does not need to be carried out on the liquid sample, and the gas concentration of the liquid sample can be directly measured.

The invention relates to a laser device, a laser control method and a charged particle beam detection system. The laser device comprises a controller, a multi-wavelength laser light source and a first dimming module. The controller is configured to match the working height of the working table and generate a wavelength selection instruction; wherein the working table is used for placing a semiconductor structure to be tested, and the working height of the working table is adjustable. The multi-wavelength laser light source is connected with the controller and is configured to respond to a wavelength selection instruction and emit a laser beam of a target wavelength. The first dimming module is located on the light emitting side of the multi-wavelength laser light source and is configured to adjust the transmission light path of the laser beam so that the laser beam can irradiate the semiconductor structure to be measured according to a first target angle. Wherein the laser beams with different target wavelengths correspondingly have different first target angles. The method and the device are used for assisting in charged particle detection so as to improve the comprehensiveness and the accuracy of semiconductor defect detection.