5615 results about "Grating" patented technology

The invention relates to the technical field of precise geometric quantity measurement, and discloses an electronic component size and contour automatic metering method, which comprises the following steps: calculating a nominal truncation phase distribution diagram of a to-be-measured electronic component by using a virtual projection imaging model, controlling a projection unit to project a single-frequency sine stripe grating to the electronic component and collecting a deformed stripe image, calculating the gradient of the modulation degree distribution map and extracting edge contour features to solve the actual pose of the assembly; performing modulo 2pi differential operation on the nominal and actually measured truncated phase distribution maps, and eliminating high-gradient artifacts by using an edge mask to generate a phase residual map; and converting the phase residual image into a height deviation distribution diagram according to the phase height mapping relation, and by constructing a phase domain differential metering channel, the phase unwrapping ambiguity in discontinuous surface measurement is avoided.

The invention discloses an aerial optical cable defect detection method based on multi-mode sensing fusion and related equipment, and relates to the field of data processing. The method comprises the following steps: acquiring multi-modal sensing data along an aerial optical cable through sensing equipment of different modals; performing time and space alignment processing on the distributed fiber bragg grating strain data, the acoustic emission signal data and the visual image data to obtain multi-mode time and space alignment data; extracting feature data of each mode based on the multi-mode space-time alignment data; performing fusion processing on the feature data of each modal through an attention mechanism to obtain fused feature data; determining a defect identification result of the aerial optical cable according to the fusion feature data, wherein the defect identification result comprises a defect type and a position of the defect on the optical cable; obtaining the result confidence of the defect recognition result; and generating a final optical cable defect detection result according to the result confidence. According to the invention, the problem that the current aerial optical cable defect detection has relatively large missed detection and false detection risks can be relieved.

The invention provides a wavelength deviation compensation method and system for rapid wavelength analysis of a far-end fiber bragg grating, and relates to the technical field of fiber bragg grating sensing, and the method comprises the steps: collecting grating reflection spectrum signals of different transmission distances, carrying out frequency domain transformation to separate phase components, and building a mapping relation between the transmission distance and dispersion cumulant; calculating an initial wavelength offset estimation value; identifying a refractive index section, and establishing a segmentation compensation coefficient; constructing a wavelength-strain-temperature three-dimensional space, and optimizing a compensation coefficient according to the trajectory curvature; and updating the compensation coefficient according to the residual gradient. The wavelength analysis precision of the far-end fiber bragg grating can be improved, and the influence of dispersion on measurement is reduced.

The invention provides an intelligent detection method and system for the tensile property of a plastic cable tie. Gradient temperature rise control is executed through the carbon fiber heating tube array, microscopic deformation fluctuation characteristics are captured through the double-grating displacement sensor, and temperature field distribution is collected through the infrared thermal imager. Establishing dynamic correlation between deformation and a temperature field to generate a three-dimensional space-time atlas, identifying a migration path of a thermal aggregation area, recording a standard path, and calculating a thermal anomaly coefficient in combination with pressure data; analyzing temperature conduction hysteresis to generate a heat conduction parameter, and dynamically correcting a threshold value by cross-modal correlation with an abnormal coefficient; a structure degradation index is generated based on the migration path, mapping between the structure degradation index and a temperature field is established to generate a thermal damage compensation coefficient, an abnormal coefficient is calibrated accordingly, and grading early warning is triggered in combination with the path deviation degree. According to the technical scheme provided by the invention, multi-scale damage evaluation from thermodynamic associated data acquisition to molecular chain fracture inversion is realized, and the high-temperature tensile failure critical point is accurately pre-judged through a dynamic calibration early warning mechanism.

The invention discloses an intelligent monitoring system for an assembled net rack shear structure, and relates to the technical field of net rack structure health monitoring. A fiber grating sensor, an ultrasonic array, an electromagnetic coil and an energy assembly are integrated through a sensor integration module and a modular support; optical fiber strain, ultrasonic signals and electromagnetic impedance data are collected in real time; after the feature fusion module extracts key features through preprocessing, a fusion feature vector is obtained through an adaptive manifold projection fusion method; the shear force value prediction module takes the fusion feature vector as input, and obtains a shear force value prediction model through training by using an LSTM (Long Short Term Memory) model; and the net rack judgment module is combined with a DBSCAN algorithm to divide neighbor sensor network groups, and is used for judging the structure defect type based on a local anomaly concentration ratio LAC and an overall cooperative change rate GCR. According to the system, intelligent monitoring of the fabricated net rack shear structure is realized, and the monitoring precision and the defect identification accuracy are improved.

The invention discloses a remote real-time monitoring and fault early warning method for a power supply operation state, and relates to the technical field of power electronics and energy management, and the method comprises the steps: collecting the temperature data of a key part of a power supply through an optical fiber Bragg grating sensor array, and analyzing the wavelength offset; electrical parameters are collected through a differential MEMS current / voltage sensor, and a permalloy / ferrite composite shielding layer is arranged in the sensor; collecting a mechanical vibration signal through a piezoelectric ceramic vibration sensor; for device data from different manufacturers, Modbus and CAN heterogeneous protocols are matched and analyzed through a regular expression, and the Modbus and CAN heterogeneous protocols are converted into a unified RDF triple format; inputting temperature, current and vibration data into a space-time alignment module, and constructing a semantic mapping relation by adopting an ontology; calculating a sensor confidence coefficient weight, and performing weighted fusion to generate an equipment health index; operating a lightweight LSTM model at an edge node, and detecting current harmonic and vibration resonance frequency band abnormity in real time; cOMSOL multi-physical field simulation is combined at the cloud end, and the evaporation rate of the capacitor electrolyte is predicted.

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.

The invention provides an eccentric butterfly valve performance detection method and system based on optical detection. The method comprises the steps that a first image of light transmission intensity distribution of a sealing pair structure of a bidirectional all-metal hard sealing four-eccentric butterfly valve is obtained; acquiring a reflection interference image of the structured light on the sealing pair structure according to the phase modulation structure grating light field, and performing conjoint analysis in combination with the first image to generate a contact pressure distribution matrix; based on the first image and the contact pressure distribution matrix, extracting corresponding multi-dimensional image features to generate a leakage early warning area map; space comparison is carried out on the leakage early warning area map and the floating response track of the sealing pair structure in the opening and closing process, and the corresponding floating response characteristics of the leakage early warning area in the opening and closing process are determined; and generating a butterfly valve sealing performance detection result according to the abnormal degree of the floating response characteristics. Through the implementation of the scheme, the leakage early warning area and the corresponding dynamic abnormal characteristics can be identified in advance, and the safety and the operation stability of the system are improved.

The invention discloses a straight gear shape-free measurement method based on single-group line structured light. The method comprises the following steps: constructing an optical platform coordinate system, carrying out line structured light coordinate system calibration through a spherical calibration body, and calibrating the rotation center of a precision turntable; installing a measured straight gear, establishing a straight gear coordinate system, and adjusting the position of the linear structure optical measuring head, so that the measuring field of view of the linear structure optical measuring head covers a root circle to an addendum circle of the straight gear; the straight gear is installed on a precision rotary table, the straight gear is driven to rotate at a constant speed, a linear structure optical probe scans and collects straight gear contour point cloud data and circular grating angle information, and tooth surface three-dimensional point cloud data is obtained; based on the three-dimensional point cloud data of the tooth surface, extracting an addendum circle, a dedendum circle and an involute tooth profile, and calculating spur gear parameters; performing reverse three-dimensional shape modification tooth surface identification on the shape modification straight gear to generate a three-dimensional deviation diagram; and outputting a measurement result and printing a report. The problems of shape-free rapid measurement, modification tooth surface identification and tooth surface three-dimensional deviation characterization of the straight gear with unknown basic parameters are solved.

The invention discloses a handheld multi-beam alignment fiber bragg grating sensing device and method. The handheld multi-beam alignment fiber bragg grating sensing device comprises a passive sensing grating assembly, a handheld module and a demodulation control module. The passive sensing grating assembly converts laser propagating in the optical fiber into a spatial light parallel laser beam and concrete an invisible passive end optical axis; the handheld module is used for realizing multi-beam high-speed space scanning and completing laser collimation and projection; and the demodulation control module is used for generating and distributing multiple paths of sensing laser and controlling the galvanometer in the handheld module to move synchronously. Due to the adoption of the hollow circular ring, the invisible virtual optical axis of the passive end can be visualized, an operator can conveniently and roughly recognize the position of the optical axis of the passive end, and the manual alignment efficiency is greatly improved. And meanwhile, one laser beam is divided into four laser beams by adopting a two-stage light beam increasing method, and the four laser beams are scanned through a galvanometer module and an off-axis parabolic mirror to form hundreds of laser beams in time, so that the space coverage is large, and the alignment efficiency is greatly improved.

The invention provides a distributed feedback laser with a double-layer grating structure, and relates to the technical field of lasers, the laser forms an InGaAlAs multi-quantum well active region, an upper sampling grating layer and a lower phase shift grating layer on an n-type InP substrate in sequence, the upper grating layer is designed based on a reconstruction equivalent chirp technology, and the lower phase shift grating layer is designed based on a reconstruction equivalent chirp technology. Two sections of asymmetric modulation areas with sampling periods linearly gradually changing in opposite directions are arranged in the axial direction of the resonant cavity, and the lower grating layer is a quarter-wave phase shift grating matched with the period of the upper seed grating. Through the synergistic effect of equivalent phase modulation and phase shift generated by the double-layer grating, the photon density distribution in the cavity can be improved, the longitudinal space hole burning effect can be weakened, the sensitivity to end face phase fluctuation can be reduced, high single-mode power and large modulation bandwidth can be realized in a wide temperature range, and the double-layer grating is suitable for a high-speed optical communication and coarse wavelength division multiplexing transmission system.

The invention discloses a heat dissipation control method and device for a single-phase immersed liquid cooling charging pile and a medium, and relates to the technical field of battery thermal management, and the method comprises the steps: carrying out the high-precision scanning and dynamic feature extraction of a built-in fiber grating array of a cold plate according to a partition flow control signal, and obtaining a temperature field matrix and a dynamic thermal feature set; performing multi-dimensional fusion analysis and electrochemical coupling analysis on the temperature field matrix and the dynamic thermal feature set to generate a thermal coupling parameter set; performing real-time risk quantitative evaluation and risk topological mapping on the thermal coupling parameter set, and outputting a risk topological data set; and performing cooling intensity dynamic modulation according to the risk topology data set, and obtaining a partition flow redistribution instruction. According to the invention, fine monitoring of the cold plate-battery interface contact thermal resistance is realized through a high-precision pressure field reconstruction technology, the accuracy and reliability of pressure distribution detection are significantly improved, and the local overheating risk caused by an assembly gap is effectively eliminated.

The invention discloses a three-degree-of-freedom measurement method based on a planar two-dimensional time grating sensor, and the method comprises the following steps: enabling a movable ruler base body and a fixed ruler base body to be installed in a parallel and opposite manner, and leaving a certain gap between the movable ruler base body and the fixed ruler base body; after same-frequency and equal-amplitude sine excitation signals with the phase difference of pi / 2 are applied to the four-phase excitation electrode groups on the fixed ruler base body respectively, the movable ruler base body moves in the X direction and the Y direction and deflects around the Z axis relative to the fixed ruler base body; the single sensing unit on the movable ruler base body can solve output signals deflecting in the X direction and the Y direction and around the axis, the output signals of all the sensing units are subjected to combined operation, and displacement values of the movable ruler base body in the X direction and the Y direction and the deflection angle theta can be decoupled. According to the method, displacement measurement in the X direction, the Y direction and the deflection angle around the Z axis can be achieved through combined calculation between the induction units on the movable ruler base body, the calculation speed is high, interference can be further eliminated, and the measurement precision is improved.

The invention discloses a calibration device with a spectrum self-calibration function and a high-resolution spectrum calibration method thereof. The device comprises a narrow-band light source, a broadband light source, an optical fiber isolator, a coupler, an interference system, a multi-way switch, an FP (Fabry-Perot) cavity, a collimator, an orthogonal dispersion system and a computer, wherein the orthogonal dispersion system consists of a cylindrical lens, a reflector, a virtual phase array, a grating, a focusing lens and an industrial camera; according to the device, different light source paths are gated, FP cavity modulation and orthogonal dispersion system light splitting are utilized, and an industrial camera is combined to receive light signals. According to the method, the mapping relation between pixels and wavelengths can be established, the two-dimensional spectrum is compressed into the one-dimensional calibration spectrum through light intensity modulation and normalization processing, the calibration process of the orthogonal dispersion system is simplified, and the measurement precision is improved; and system drift can be compensated in real time through self-checking calibration, and the reliability of a measurement result is ensured, so that accurate calibration and measurement of a high-resolution spectrum can be realized.

A device includes a photonic routing structure including a silicon waveguide, photonic devices, and a grating coupler, wherein the silicon waveguide is optically coupled to the photonic devices and to the grating coupler; an interconnect structure on the photonic routing structure, wherein the grating coupler is configured to optically couple to an external optical fiber disposed over the interconnect structure; and computing sites on the interconnect structure, wherein each computing site includes an electronic die bonded to the interconnect structure, wherein each electronic die of the computing sites is electrically connected to a corresponding photonic device of the photonic devices.

The invention provides a curved surface local grinding and polishing trajectory planning method and a grinding and polishing system, and relates to the technical field of grinding and polishing machining. According to the curved surface local grinding and polishing trajectory planning method, workpiece point clouds are collected, simplification and filtering are carried out, the number of effective voxels is reduced, and the operation processing efficiency is improved; the method comprises the following steps: extracting a damaged area, determining a grinding and polishing area according to the damaged area, planning the grinding and polishing area according to surface topography characteristics of a workpiece, constructing a grating path corresponding to the grinding and polishing area based on workpiece point cloud, and converting according to the grating path to obtain a workpiece grinding and polishing path so as to realize accurate and efficient grinding and polishing operation. Besides, the normal pressure of the grinding and polishing tool corresponding to the grinding and polishing path of the workpiece is calculated in combination with coupling of the surface curvature of the workpiece, the normal pressure of the grinding and polishing tool can be adjusted in real time, concave area force increasing and convex area force reducing are achieved, the over-grinding problem of the curved surface workpiece can be effectively avoided, and accurate grinding of the area boundary is achieved.

The invention belongs to the technical field of optical fiber sensors, and particularly relates to a distributed optical fiber magnetic sensor, a preparation method thereof and a distributed measurement system. The optical fiber comprises an optical fiber and a magnetic composite matrix, a magnetic field measurement grating and a temperature compensation grating are arranged on the optical fiber; the magnetic composite matrix is formed by curing a magnetic composite suspension coating the outer side of the magnetic field measurement grating, the magnetic composite matrix comprises cured resin and magnetostrictive material particles uniformly distributed in the cured resin, and the magnetostrictive material particles are arranged in the cured resin in a predetermined orientation manner, so that the space monitoring range is expanded, and the magnetostrictive material particles are uniformly distributed in the cured resin; multi-point parallel measurement is achieved, and the defect that single-point measurement is prone to being disturbed by a local magnetic field is overcome; the technical problems of high precision, low cost, difficulty in deployment and long-section measurement of a magnetic field measurement sensor in the prior art are solved.

The invention provides a continuous depth gradually-changing grating structure based on a silicon carbide substrate and a preparation method thereof. The preparation method comprises the following steps: forming a sacrificial layer with gradually-changing thickness on the silicon carbide substrate; etching is carried out by adopting a two-step plasma etching process; and polishing the surface through a plasma polishing process. According to the invention, the gradient sacrificial layer is combined with two-step plasma etching, and a high-precision continuous depth gradient grating structure is realized on the silicon carbide substrate, so that the diffraction requirements of RGB three-color wavelengths are met; the micro-groove defect in the etching process is eliminated, the problem that the depth-to-width ratio and the surface quality cannot be considered in the traditional process is solved, and a key technical support is provided for mass production of the single-layer full-color optical waveguide; the transmission loss of the optical waveguide is reduced by controlling the surface roughness; and the product yield is improved, the production cost is reduced, and the method is suitable for large-scale production.

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.

The invention relates to the technical field of sensors, and provides a grating position sensor. A scanning assembly and a light source module are relatively fixed, and an incident diaphragm and an increment detector are arranged in the scanning assembly; the increment detector is spatially divided into at least two first detector regions for detecting a first phase increment signal component and at least two second detector regions for detecting a second phase increment signal component, and the at least two first detector regions are spatially separated from each other; performing redundant detection on the first phase increment signal component; the at least two second detector areas are separated from each other in space so as to perform redundancy detection on the second phase increment signal component; the position metering element is suitable for being fixed on a measured object or a measuring datum plane and can generate relative displacement with the scanning assembly. The invention provides a grating position sensor with strong anti-pollution capability. The grating position sensor can keep a high-reliability working state for a long time in a complex or severe industrial environment.

Sleep-aiding eyewear that prevents light which inhibits melatonin production from reaching the eye is described. The eyewear that is the object of the present disclosure has improved visibility over other methods of cutting off melatonin-inhibiting wavelengths of light, which enables the user to perform tasks, such as reading and typing, uninhibited. This is achieved in some embodiments using a Bragg grating comprising multiple layers of alternating reflective index material as a surface coating on the lens. This may be combined with lens-tinting, or antireflective coatings, in the eyewear. Furthermore, transition lenses which block melatonin-shifting light when there is a suitable external stimulus, such as blue light from a light emitting diode, are described. The presently described filters are also useful for electronic displays and functional light-transmitting materials.

Disclosed is a wearable electronic device. The wearable electronic device includes: a display module comprising a display; a housing to which the display module is coupled; and a projection display disposed on a side portion of the housing and configured to display information on a display area adjacent to the housing, the projection display may include: a substrate disposed along a mounting surface provided on a side portion of the housing; a plurality of light-emitting devices comprising light-emitting circuitry disposed on the substrate in a grating arrangement; and a plurality of micro-lenses covering a light-emitting surface of the plurality of light-emitting devices.

The invention relates to wafer detection, in particular to a data calibration and wafer scanning data alignment method based on polar coordinate sampling, and the data calibration method based on polar coordinate sampling comprises the steps: carrying out the alignment of the collection data of a photoelectric detector and the periodic data of a grating type displacement sensor; determining a time point for starting detection and a time point for ending detection, and cutting the collected data; counting the scanning period of the grating type displacement sensor according to the data width of the current sampling timestamp; scanning the cross-period signals in the clipped acquisition data, and determining the relative offset of each cross-period signal; according to the scanning period of the grating type displacement sensor and the relative offset of each cross-period signal, position offset calibration is carried out on the collected data in each period; according to the technical scheme provided by the invention, the defect that the position deviation of the acquired data caused by the speed fluctuation of the motion shaft is difficult to effectively calibrate and align in the prior art can be effectively overcome.

The invention relates to a naked eye 3D binocular image acquisition and real-time processing system based on hardware synchronous triggering, and belongs to the technical field of image processing and three-dimensional display. According to the system, a hardware synchronous triggering mechanism is adopted, a time sequence synchronous control unit is used for sending a synchronous pulse signal to a binocular image sensor, and strict synchronization of left and right viewpoint image acquisition is ensured. The image signal processing unit processes collected original data, the stereo parallax correction module performs epipolar correction, and the sub-pixel interleaving module generates a composite view frame according to grating parameters of the display terminal. The system realizes high-speed data transmission through a double-buffer direct memory access DMA mechanism. The problems of visual tearing and weak stereoscopic impression caused by asynchronous binocular image acquisition in the prior art are solved, nanosecond-level synchronization precision is realized, optical crosstalk is reduced, and smoothness and comfort of stereoscopic display are ensured.

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.

The invention discloses a high-temperature-resistant flame-retardant carbon fiber cable and an intelligent preparation method thereof, and relates to the technical field of power cables, and the cable is composed of a composite bearing core, a first / second electrical isolation belt, a stranded conductor, an annular composite bearing layer, a high-temperature-resistant main insulator and a low-smoke halogen-free outer sheath. The force bearing core is formed by bundling carbon fiber micro rods, elastic reset layers are arranged between the micro rods, micro-particle friction layers are formed on the outer surfaces of the micro rods, and a stable friction-rebound interface is constructed. A fire-resistant barrier, a phase change microcapsule filling layer and a fiber bragg grating can be arranged, and fire resistance, thermal peak suppression and on-line monitoring are considered. And closed-loop control of pultrusion, surface activation, coating and on-line thickness measurement / friction test is carried out in the manufacturing process. The cable can be operated at 200 DEG C for a long time and at 250 DEG C for a short time, the residual elongation is less than or equal to 0.10%, and light weight, high strength, high temperature resistance, low smoke and flame retardance are realized.

The invention provides a tunable laser source output wavelength adjusting device and method, and the method comprises the steps: starting a tunable laser source, carrying out the preheating, and resetting a motor motion unit; acquiring an initial light-emitting wavelength based on a pre-stored relation curve between the light-emitting wavelength of the laser source and the position of the motor; controlling the output wavelength of the laser source through the coarse tuning parameter of the motor motion unit, traversing the tunable output range of the tunable laser source, and collecting the wavelength position of the reflection peak value of the fiber bragg grating and the corresponding optical power value; according to the reflection peak wavelength position, through voltage regulation and control of stacked piezoelectric ceramics, step scanning is carried out according to a target wavelength, and a laser source output wavelength is dynamically adjusted to obtain a fine scanning wavelength; and judging whether the deviation between the fine scanning wavelength and the target wavelength meets the preset precision or not, if so, locking the output wavelength, otherwise, repeatedly regulating and controlling until the conditions are met. According to the invention, traditional current-wavelength dependence is broken through, and wavelength demodulation is realized through electromechanical collaborative calibration and two-stage scanning.

The invention discloses a parallel imaging OCT (Optical Coherence Tomography) system based on a metasurface area array, which relates to the technical field of medical instruments, is small in size and can realize intraocular single-shot area array imaging and a three-dimensional position depth perception function by using metasurface and optical coherence tomography imaging information in a sample tissue with a limited size. According to the technical scheme, a light beam emitted by a laser is divided into two paths through a beam splitter, and the two paths enter a sample arm module and a reference arm module respectively; the sample arm module is a probe and comprises a multi-core optical fiber and a first metasurface; the reference arm module comprises a collimator, a motor and a right-angle reflector; the probe enters a sample tissue, a light beam is focused on the sample tissue and then is backscattered, the backscattered light beam reversely passes through the first metasurface, the multi-core optical fiber, the beam splitter, the second metasurface, the third lens, the grating and the focusing lens and then forms a spectral line beam on the CCD sensor, and the computer reads a signal from the CCD sensor and performs three-dimensional reconstruction imaging on the sample tissue.

The invention belongs to the technical field of image processing, and particularly relates to a coded disc surface tiny scratch recognition method based on micro texture feature analysis, which comprises the following steps: acquiring a coded disc grating texture image and converting the coded disc grating texture image into a rectangular coordinate system to obtain an expanded grey-scale map; the optimal main direction of the grating texture is determined through rotation projection analysis; for each pixel point in the grey-scale map, sampling along two sides of the optimal main direction to form a reference sample; calculating a weighted average value of the gray values of the sample points in the reference sample to obtain a trend prediction value, calculating a residual error between the gray values of the pixel points and the trend prediction value, and determining a texture deviation index in combination with the change condition of the gray values of all neighborhood pixel points of the pixel points; and finally, identifying the scratches through threshold segmentation. According to the method, the grating edge interference can be effectively inhibited under the strong periodic texture background, and the tiny scratch features can be accurately extracted.

The invention provides a railway safety protection system, which comprises a laser correlation detection module formed by a laser transmitting end and a laser receiving end symmetrically arranged on two sides of a railway opening and used for generating a plurality of groups of laser grating networks and monitoring a light beam shielding event in real time; the intelligent analysis module is used for identifying the type of an intrusion target according to the shielding signal of the laser grating network and analyzing a target movement track to filter false triggering; the alarm linkage module is used for triggering a sound-light alarm after the invasion is confirmed, closing a railway barrier gate and sending alarm information to a control center; the monitoring integration module is used for being linked with a video monitoring system to call the high-definition image of the intrusion area and assisting in judgment through AI image recognition; and the environment self-adaption module is used for integrating a temperature and humidity sensor and a wind speed sensor to dynamically adjust a laser sensitivity threshold value to adapt to environment change. Personnel invasion at the railway crossing of the thermal power plant is monitored through a laser correlation technology, so that unauthorized personnel or vehicles are prevented from entering a railway transportation area of the thermal power plant, and the operation safety of the thermal power plant is guaranteed.