102 results about "Angular scan" patented technology

The invention discloses a double-domain artifact correction method based on multi-energy-level data and physical prior fusion, and the method achieves the efficient and precise removal of dispersive metal artifacts through the construction of a complete technical scheme of the combination of multi-energy-level data collection, double-domain cooperative correction and physical model constraint. The system has the beneficial effects that the system covers multiple fields of medical treatment, industry, security and protection, aerospace and the like, and has extremely high universality and adaptability. On the basis of a multi-energy-level slow switching scanning protocol, full-angle scanning of at least two energy levels is completed by dynamically adjusting radiation source parameters, and obtained complete multi-energy-level projection data is converted into a high-dimensional tensor through a channel dimension splicing image fusion method. The constructed multi-channel virtual image completely retains attenuation characteristics and structure information of a target object under each energy, provides a more comprehensive input source with discrimination for a deep learning network, builds a data basis for accurate correction in different fields fundamentally, and adapts to various imaging scenes containing metal targets.

The invention belongs to the field of CT (Computed Tomography) tomography reconstruction technology and artificial intelligence, and discloses a finite angle CT reconstruction method based on combination of a three-dimensional conditional diffusion model and synchronous iteration. The CT is an imaging technology which utilizes X-rays to irradiate a target from different angles and acquire projection, and obtains an internal three-dimensional structure through reconstruction. Different from traditional CT depending on nearly full-angle scanning, the method only collects limited-angle projection, and achieves fault reconstruction under the limited-angle condition through a three-dimensional condition diffusion model of space domain-frequency domain two-way decoding and by means of structural generality priori of a workpiece. Meanwhile, projection and fault data consistency correction is carried out in combination with a synchronous iteration reconstruction technology, the advantages of an iteration method in the aspect of physical mechanism characterization are exerted, interpretable physical constraints are provided for a deep learning network, and therefore the reliability and precision of a reconstruction result are improved.

The invention discloses a power distribution station multi-point environment control system and method, and relates to the technical field of power system automation, and the method comprises the following steps: building a time-frequency phase-locked observation baseline based on the scattering relation between an infrared band and water vapor under the condition of sudden humidity increase, inverting aerosol particle size distribution and concentration distribution, and generating a multi-dimensional scattering phase residual field; according to the multi-dimensional scattering phase residual field, a real radiation field is reconstructed by adopting multi-path reverse ray variation solution and combining polarization dual-angle scanning, and a reflection saturation risk spectrum is generated. According to the method, a real radiation field is reconstructed through multi-dimensional observation and inversion, a consistency graph is generated by fusing multi-source data, a misjudgment boundary is accurately identified, a control margin and a switching condition are constructed based on residual playback and time correction, and a steady-state closed-loop control chain is formed in combination with a dynamic regulation and control mechanism. The self-adaptive precise regulation and control of the power distribution station environment and the stability guarantee of the thermal field are realized.

The present invention provides a computer-implemented method for X-ray analysis. The method includes receiving X-ray analysis data from an X-ray detector having multiple detection channels. The X-ray analysis data includes angular scan intensity data obtained by measuring X-ray intensities when successively scanning the X-ray detector. A series of intensity measurement values ​​is acquired for each detection channel. Each series of intensity measurement values ​​is an intensity angular scan. An angular offset is determined for each detection channel. The method further includes determining, for each of a plurality of detection angle bins, an intensity contribution factor for at least one of the intensity measurements. The intensity contribution factor is determined according to an angle range associated with the detection angle bin and the angular offset of the detection channel. For each of the plurality of detection angle bins, a binned intensity is determined based on the intensity of the at least one intensity measurement value and its corresponding intensity contribution factor.

The invention discloses a PVC film coating uniformity detection method based on spectral analysis, and relates to the technical field of optical detection, and the method comprises the following steps: S001, adopting a controllable incident illumination system with a multi-angle rotation function to carry out continuous angle scanning on the surface of a PVC film, collecting reflection spectrum intensity data in a corresponding wave band range according to different incident angles, and generating a spectrum data matrix containing interference characteristics; and S002, carrying out continuous wavelet transform processing on the spectral data matrix, carrying out multi-scale local decomposition on a spectral response signal, extracting and separating a periodic interference characteristic signal, and obtaining a purified spectral matrix after interference reduction. According to the method, through multi-angle spectrum collection and interference feature stripping, accurate identification of a coating thickness abnormal area and combination of strength indexes, spraying parameters are regulated and controlled, a detection-compensation-reinspection closed-loop mechanism is constructed, interference misjudgment is effectively avoided, and the accuracy and regulation and control efficiency of uniformity detection of the PVC film coating are improved.

The invention discloses a defect local resonant frequency extraction method based on vibration response space clustering analysis, and belongs to the field of nondestructive testing. The method comprises the following steps: processing an ultrasonic detection data set, calculating a difference function between a frequency spectrum of each scanning point and an average frequency spectrum, extracting a local maximum frequency, carrying out frequency statistics, and screening out an abnormal response frequency; in combination with the spatial distribution characteristics of the detection points, identifying a frequency cluster with spatial aggregation by adopting a density clustering algorithm to form a candidate local resonant frequency set; and constructing an intensity matrix under the candidate local resonant frequency, extracting energy attenuation characteristics in each direction by using an equal-angle scanning method, and comparing the energy attenuation characteristics with a preset threshold value to determine the defect local resonant frequency. The method does not need to preset defect positions and geometric features, can realize automatic extraction of the defect local resonant frequency under the condition of unknown defects, has the advantages of high identification precision, strong anti-interference capability, high calculation efficiency and the like, and is suitable for non-destructive testing requirements in an engineering environment.

The invention discloses an engineering pile hole-forming quality detection method based on an intelligent interconnection foundation platform, and relates to the technical field of engineering pile quality detection, and the method comprises the steps of S1, task issuing and data docking, S2, probe deployment and mud sound velocity calibration, S3, ultrasonic hole wall scanning, S4, sediment thickness measurement, S5, real-time data processing and twinborn feedback, and S6, quality evaluation and decision making. A plurality of groups of transducers are used for scanning a hole wall section at double angles through an orthogonal cross transducer array, millimeter-level distance measurement is realized through an ultrasonic total reflection principle, measurement errors caused by stretching and winding of a traditional measuring rope are avoided, a sediment interface is verified through pressure sudden change points and probe dip angle probe-dip angle coupling measurement, and the measurement accuracy is improved. The problem that a traditional measuring rope is touched by soft mud by mistake is solved, lowered design pile position information is automatically received, the method is suitable for complex stratums such as a pebble bed and a quicksand bed, a visual report and a hole forming model are generated, the recording efficiency is improved, and the hole collapse risk is reduced.

The invention discloses a three-coordinate measuring machine based on special-shaped surface measurement. An upper working surface where a working table is located is used for bearing a to-be-measured piece; the measuring mechanism is arranged on the moving portal frame, the moving portal frame is made to move on the workbench, and a to-be-measured piece is measured through the measuring mechanism. A measuring head of the measuring mechanism is arranged at the front end portion where the first movement assembly is located, meanwhile, a first air bag pushing piece is arranged at the rear end portion where the first movement assembly is located, and the first air bag pushing piece is inflated and deflated to be matched with a measuring head piece at the front end portion to synchronously achieve axial pivoting movement. And the second movement assembly is located above the first movement assembly, so that the pivoting movement of the first movement assembly and the second movement assembly drives the measuring head piece to move in the whole space direction, and the full-angle scanning measurement of the to-be-measured piece by the measuring head piece is formed. The whole device can realize high-precision measurement of small-size measurement pieces, and the measurement efficiency is improved.

The invention discloses an industrial part surface defect intelligent detection system and method, and relates to the technical field of defect detection. When a part is fixed on a rotating carrier for full-angle scanning, a surrounding type industrial camera and a light source array cooperate, a light field is dynamically evaluated by combining part curved surface reflection characteristics, and the light source intensity and direction and camera exposure and gain are adjusted; obtaining a uniform initial image; a global image of the part is reconstructed through brightness standardization, denoising interference suppression, multi-scale texture enhancement, distortion correction, normal expansion and cross-view alignment splicing; the method comprises the following steps: extracting cross-scale features by adopting a graph convolution attention model, constructing a fusion feature vector based on geometric morphology parameters and texture features by virtue of defect regions segmented by regional reconstruction aggregation curved surface reflection to finish classification and grading, generating a simulated graph through an adversarial generative network, comparing and verifying, and outputting a detection report. The defect detection precision and efficiency are effectively improved, and the industrial high-quality detection requirement is met.

The present application relates to the technical field of ultrasonic nondestructive testing and industrial pipeline safety evaluation, in particular to a kind of stainless steel pipeline weld internal defect detection system, comprising: obtaining ultrasonic multi-angle scanning data, extracting waveform features and sound path information;Anisotropic propagation model is constructed, and sound beam deflection correction factor is solved;Generate corrected sound field spatial distribution data;Calculate the multi-view spatial coherence coefficient representing the consistency of signal phase under different sound beam paths;If the multi-view spatial coherence coefficient is greater than the coherence threshold, then determine that the corresponding signal is a defect echo, and reconstruct the defect spatial morphology;Otherwise, it is determined that the corresponding signal is structural scattering noise, and noise suppression processing is performed;Output the quality detection report of target component;The present application solves the missed detection hidden danger caused by geometric constraint and material attenuation, and ensures that the detection result of nuclear power and petrochemical high-risk pipeline under complex physical conditions meets the stringent full-coverage quality standard.

The invention provides a one-dimensional wide-angle scanning phased-array antenna based on a multimode substrate integrated waveguide. The one-dimensional wide-angle scanning phased-array antenna comprises a plurality of antenna units, a rectangular SIW cavity structure formed by a plurality of first metalized via holes connected with the metal bottom plate is arranged at the position, close to the periphery, of each antenna unit radiation patch; and two symmetrical rectangular radiation slots, a rectangular mode fusion groove and two rows of second metalized via holes are etched in the SIW cavity on the radiation patch. According to the SIW cavity structure, the defect of relatively high transmission loss caused by easy leakage of a fringe field in the prior art is avoided, and the scanning range of a wave beam is effectively widened; the rectangular mode fusion groove and the two rows of second metalized via holes change the current path when the antenna works, realize effective fusion of TE10 and TE30 resonant modes, effectively widen the working bandwidth of the antenna and the 3dB beam width of a radiation pattern, and are used for solving the problems of narrow working bandwidth and small beam scanning range in the prior art.

The invention provides a high strabismus imaging method and system for cooperative scanning of an agile attitude and a load. The method comprises the following steps: calculating optimal imaging parameters of a high strabismus mode; establishing a load high-squint stripe imaging method under satellite level flight and left and right side-looking attitudes; establishing an SAR imaging coordinate system in a posture and load cooperative scanning state; establishing an attitude agile maneuvering and load electric scanning coordinated slip aggregation mode implementation method; and establishing an azimuth large squint multi-target mode observation mode. According to the invention, the agile maneuvering capability of the satellite platform and the large-angle scanning capability of the load phased-array antenna are fully utilized, and the agile maneuvering capability of the satellite platform and the large-angle scanning capability of the load phased-array antenna cooperate to realize in-orbit large-squint imaging, so that the method has popularization and practical values for improving the in-orbit application efficiency of light and small

The invention relates to the technical field of visual inspection, and discloses a vagina electrode three-dimensional curved surface defect detection system and method based on machine vision, and the vagina electrode three-dimensional curved surface defect detection system comprises a base station and a controller installed on the base station. When the visual detector detects the end of the electrode, the ejector rod moves upwards to drive the connecting frame to move, the protrusion at the tail end of the connecting frame slides along the strip-shaped groove of the rocker arm, the rocker arm is pushed to rotate, the angle of the visual detector is adjusted, the design can adapt to the radian difference between the curved surface of the end and the rod body, and the end detection blind area caused by angle fixation is avoided; tiny defects at the end part of the electrode can be accurately captured, and the requirement of medical equipment on the whole surface integrity of the electrode is met; and in a system resetting stage after the end detection is completed, the visual detector does not recover to the initial detection angle and forms a differentiated visual angle with the angle when the rod body is initially detected, and through secondary differentiated angle scanning in the resetting process, the missing detection defect caused by shadow shielding and a curved surface reflection blind area at the initial angle can be effectively captured.

The invention relates to a simulation scanning method for guiding the routing angle of adjacent layers, and the method comprises the steps: building a transmission line model containing two pairs of differential lines with the vertical projections of the adjacent layers coinciding, setting a center coordinate, controlling the two pairs of differential lines to rotate reversely at the same value, scanning the angle, obtaining crosstalk data of different angles through simulation, and improving the amplitude. Therefore, the wiring angle design of adjacent layers is guided. According to the method, two pairs of differential lines of adjacent layers are set as reverse same-value rotation variables, the angle difference and a single variable are associated, control is simplified, and traceability is achieved; a projection center is used as a rotation reference, so that accurate control and reliable simulation are guaranteed; crosstalk data are obtained through angle scanning, quantization limitation is broken through, and efficiency is improved; the data shows that the difference is improved, the optimal angle is selected by combining the assistance with the space limitation, crosstalk exceeding or space waste is avoided, and experience dependence is got rid of.

Systems and methods for calibrating a radar sensor based upon synthetic aperture radar (SAR) principles are described herein. A relative motion is induced between a radar sensor and a calibration target in the field-of-view of the radar sensor. The radar sensor receives returns from the calibration target. The radar sensor outputs, based upon the relative motion between the radar sensor and the calibration target, detections that are indicative of locations of points on the calibration target. A computing system generates calibration data based upon the detections, the calibration data comprising a correction factor between a position measured by the radar sensor and a corresponding true position of an object. The computing system programs the radar sensor based on the calibration data such that subsequent to being programmed, the radar sensor outputs detections based upon radar returns and the calibration data.

The invention discloses a laminated scanning imaging system and an imaging algorithm based on inclined illumination multi-angle rotation fusion, and relates to the technical field of computational optical imaging. A sample is obliquely illuminated and scanned through a coherent light source, and a series of diffraction information of the sample to be detected in the illumination direction is obtained; and then rotating the angle of the sample to change the illumination direction, repeating the steps to obtain a series of diffraction information at multiple angles, and based on the diffraction information at multiple angles, performing reconstruction through an iterative algorithm to obtain a complex amplitude image of the to-be-detected sample. According to the invention, by means of inclined illumination and sample rotation, multi-angle diffraction information of the sample to be measured is fused in an algorithm, and a high-resolution reconstruction result is obtained. Meanwhile, the technology does not require height superposition of scanning positions at different angles, and has very strong experimental feasibility.

The application provides a dual-polarized planar tightly coupled array antenna, wherein the antenna unit comprises a metasurface matching layer, a radiator and a metal floor, the upper surface of a radiation plate in the radiator is provided with a cross-shaped boss fixed with the metasurface matching layer, and the metal floor is fixed with a metal wall composed of two cross metal plates, the upper end of the metal wall penetrates through the radiation plate and is connected with the metasurface matching layer, and the antenna works through exciting the connecting slot gap formed between adjacent radiators. The gap formed by the cross-shaped boss and the upper end of the metal wall can be equivalent to a capacitive load to offset the inductance generated at low frequency, the metal wall can break the original loop mode resonance, the radiation plate avoids the introduction of common mode resonance, the bandwidth at low frequency is widened, meanwhile, the metasurface matching layer can transform the impedance between the radiator and the free space, the impedance stability during wide-angle scanning of the antenna is improved, and the structure is simplified.

The application discloses a nonlinear calibration method and device of a magnetic encoder. The method comprises the following steps: setting multiple inflection points on an angle curve diagram formed based on an angle scanning result to divide an angle period into multiple angle curve segments, wherein each angle curve segment is approximately a first-order curve; acquiring a compensation coefficient of each angle curve segment; acquiring an angle output threshold value of each angle curve segment; and starting calibration after detecting a data valid signal, acquiring a target output angle after calibration based on the corresponding compensation coefficient and the angle output threshold value according to an input angle. The application divides a complete angle period into multiple angle curve segments by setting multiple inflection points, and each angle curve segment is approximately a first-order curve. Then, the slope of each angle curve segment is approximated to 1 through a compensation coefficient, and a target output angle compatible with an angle measurement value of an angle measuring instrument is obtained after calibration. The compensation algorithm is simplified, and resource consumption is reduced.

The present disclosure describes a system and a method for an ion implantation (IMP) process. The system includes an ion implanter configured to scan an ion beam over a target for a range of angles, a tilting mechanism configured to support and tilt the target, an ion-collecting device configured to collect a distribution and a number of ejected ions from the ion beam scan over the target, and a control unit configured to adjust a tilt angle based on a correction angle determined based on the distribution and number of ejected ions.

The application discloses a wide-angle scanning transmission array antenna, which comprises gradient phase surfaces I and II and a feed source, wherein the gradient phase surfaces I and II each comprise a plurality of array element units; the gradient phase surface I comprises a double-opened loop as a transmitting unit and a cut-corner patch as a receiving unit, and the double-opened loop and the cut-corner patch share a metal ground plate and are connected through a metal through hole; the gradient phase surface II comprises two cut-corner patches sharing a metal ground plate, and the two cut-corner patches are respectively used as a transmitting unit and a receiving unit; the double-opened loop comprises a radiation opened loop and a parasitic opened loop, the radiation opened loop is used for generating a circularly polarized wave, and the parasitic opened loop is used for adjusting a beam pointing direction to an inclined angle; a U-shaped groove is arranged in each cut-corner patch, and each cut-corner patch is rotated by a preset angle around the corresponding metal through hole; and the feed source is used for radiating a circularly polarized wave. The application can improve the scanning angle from two aspects of phase and amplitude.

The present invention belongs to the technical field of angle locators for ablation biopsy needles. Disclosed is an angle locator for ablation biopsy needle puncture under CT guidance. During movement, a main gear at the outer end of a rotating rod drives a first driven gear and a second driven gear to perform linkage, so as to drive a right-hand threaded screw and a left-hand threaded screw to rotate; then during rotation, the right-hand threaded screw and the left-hand threaded screw push an abutting pad to extend outward for fixation, thereby realizing the fixation function during movement, and achieving a double-linkage function. The abutting pad also can be manually rotated to move outward and inward. By using an inner angle scanning member in cooperation with angle marking holes, the rotation angle of a biopsy needle angle adjustment member can be measured during rotation, thereby improving the rotation accuracy and also allowing quick focusing. Moreover, an alignment laser is used in cooperation with a biopsy needle placement slot, so that by correspondingly aligning the focus point of the alignment laser and the focus points of a fixed laser and a rotating laser, the function of independently adjusting a biopsy needle can be realized.

The application discloses a light paper-based planar lens for electromagnetic wave beam steering and a planar antenna thereof, and belongs to the technical field of antennas. The paper-based main body is formed by surrounding a periodic interval arranged cavity structure with a sheet-shaped paper-based body, and has two opposite planes, i.e. an incident plane and an emission plane of electromagnetic waves; the sheet-shaped paper-based body is distributed with symbol units of a film-shaped metal material; the symbol units are compared with the metal surface area of the symbol units in a unit volume in the paper-based main body, and the metal surface area of a unit volume in the middle of the planar lens is greater than that of the periphery of the planar lens. The planar antenna further comprises a feed source which is installed close to the incident plane; electromagnetic waves propagate in the planar lens in a curved path and converge to be emitted out of the planar lens. When the feed source moves, the application can realize wide-angle scanning of the beam, and in a scanning range of ±50 degrees, the gain of the planar antenna decreases by less than 2dB, and very high gain and aperture efficiency can be achieved.

A reliability data obtaining system and method using multi-angle scanning includes a scanner configured to scan an object at multi-angles and a controller configured to generate and align real-time three-dimensional (3D) surfaces based on a plurality of pieces of data obtained from the scanner and assign characteristic information to unit cells included in the real-time 3D surfaces obtained via multi-angle scanning. The characteristic information may include a resource density, a curve of an object, an object color, a reliability color, position information, etc. According to the disclosure, a degree of accumulation of the resource density may be limited according to the position information so that data having various angle ranges may be accumulated in each unit cell. Thus, an intraoral model having minimized data distortion and having high reliability may be obtained.

The application discloses a dual-polarized pattern reconfigurable antenna with polarization independent adjustment, and solves the problem that each polarization of a reconfigurable antenna using a single reconfiguration device can only be one-dimensionally scanned through the particularity of a horizontal polarization layer and a vertical polarization layer. Each polarization can be two-dimensionally deflected in an E plane and an H plane, that is, can be deflected up, down, left and right. The reconfigurable antenna controls surface current, and the two polarized antennas are respectively located on the upper and lower surfaces of a dielectric substrate, and the surface current cannot pass through the dielectric, so the control of the two polarizations of the dual-polarized antenna does not affect each other. When the reconfigurable antenna is applied to a base station array antenna, the two polarizations can be simultaneously deflected in different directions, so that a multi-beam antenna can be realized, and different users in different directions can be simultaneously served. On the premise of not increasing the number of array antennas, the communication capacity of the base station antenna is greatly improved. As a pattern reconfigurable antenna, the problem of gain collapse when the array antenna is large-angle scanned can be compensated.

The invention discloses a contour parameter detection system and process for a silicon single crystal crude wafer, and the system comprises a holographic projection scanning module which generates a composite light beam by adopting a multi-wavelength laser beam combination technology, and relates to the technical field of semiconductor material detection. According to the contour parameter detection system and process of the silicon single crystal coarse wafer, all-directional and multi-angle scanning of the silicon single crystal coarse wafer can be realized through the holographic projection scanning module, the whole surface and subsurface area are covered, and the problem of limited detection range in the prior art is effectively solved; the conditions of missing detection of a key area and incomplete coverage of a core area are avoided, and meanwhile, the quantum sensing detection module has extremely high detection sensitivity based on quantum entanglement and quantum interference principles, and can sense tiny magnetic field, electric field and stress changes on the surface and in the silicon single crystal crude wafer, so that microdefects are accurately detected, and the detection accuracy is improved. The problem of insufficient microdefect detection sensitivity in the prior art is solved.

The invention belongs to the technical field of millimeter wave phased-array antennas, and particularly discloses a circularly polarized spherical phased-array antenna for Ka-band operation, which comprises a hemispherical antenna base and a plurality of radiation units, the plurality of radiation units are arranged on the hemispherical surface of the hemispherical antenna base in an array form; the circularly polarized spherical phased-array antenna is configured in a frequency range from 27GHz to 29GHz, so that + / -90-degree beam scanning of any azimuth tangent plane is realized. The scanning angle limitation of a planar array is broken through, and + / -90-degree continuous scanning of any tangent plane is realized; meanwhile, the array element spacing and the arrangement density are optimized in combination with the short wavelength characteristic of the Ka wave band, the mutual coupling effect of the high frequency band is reduced, and the problem that the actual use effect is poor due to the fact that the large-angle scanning radiation capacity of an existing Ka wave band planar phased array antenna is limited and the polarization purity is reduced is solved.

The invention provides a multi-antenna angle scanning and capturing method and related equipment, and relates to the technical field of wireless communication. The method comprises the following steps: receiving electromagnetic wave signals about a target sent by a plurality of antennas, and carrying out signal preprocessing to obtain multiple paths of baseband complex signals; performing angle scanning on the multiple paths of baseband complex signals by adopting a MUSIC algorithm to obtain an angle spectrum containing a plurality of spectrum peaks, and extracting a plurality of candidate angle values from the angle spectrum; determining a corresponding sector range around each candidate angle value, and executing tracking scanning on each sector range in parallel within a preset time to obtain a power metric value of each sector range; and performing time smoothing processing on the power metric value of each sector range to obtain a smooth power value of each sector range, and when a target sector range of which the smooth power value meets a preset condition exists, performing angle scanning in the target sector range to obtain a target angle value. By adopting the method, the real orientation of the target can be identified.

This utility model relates to the field of holographic cable defect detection technology, and more particularly to a multi-angle scanning holographic cable defect detector. Technical solution: A multi-angle scanning holographic cable defect detector includes a mounting base, a rotating shaft, a fixing block, a turntable, a detector, probes, and a control panel. A rotating shaft is rotatably connected to the upper part of the mounting base, a fixing block is fixedly connected to the rotating shaft, a turntable is rotatably connected to the top of the fixing block, a detector is fixedly connected to the left side of the turntable, probes are fixedly connected to both sides of the left side of the turntable, and a control panel is fixedly connected to the top of the turntable. This utility model uses a first motor to drive a screw rod to rotate, which in turn moves a rack and pinion, causing the detector's fixing block to rotate synchronously. This achieves precise adjustment of the vertical angle of the cable detector, ensuring comprehensive scanning of the cable from all angles and avoiding the problem of missing potential defects due to limited viewing angle.

The invention provides an optical element detection method and system based on multiple illumination modes and deep learning, and relates to the field of engineering optics. The optical element detection method comprises the following steps: applying a total internal reflection illumination mode, a front surface low-angle scanning illumination mode and a rear surface low-angle scanning illumination mode to an optical element; acquiring a corresponding total internal reflection dark field image, a front surface dark field image and a rear surface dark field image; processing the total internal reflection dark field image, the front surface dark field image and the rear surface dark field image to obtain optical defect information containing defect types and corresponding defect sizes of the front surface and the rear surface of the optical element; and processing the optical defect information by using a defect identification model based on a convolutional neural network, counting the number of damages and pollutants on the front and rear surfaces of the optical element in different size ranges, and performing optical rating to obtain defect information.

Sensor system for a construction machine, especially a road construction machine or paving machine, including: an optical detector which is arrangeable on the construction machine and configured to scan the underground in a predetermined angle so as to obtain measurement data describing one or more intensity values and / or one or more distance values plotted over the predetermined angle and a processor which is configured to analyse the measurement data so as to determine a pattern of intensity values and / or distance values in accordance with a predetermined pattern out of one or more predetermined patterns.