31 results about "Speckle field" patented technology

The invention provides a three-dimensional mining-induced stress monitoring device and method based on optical micrometer micro-deformation, and belongs to the technical field of underground coal mine engineering mining-induced stress testing. The device comprises a speckle field image monitoring module, an image acquisition module and a data storage and transmission module; the speckle field module is used for providing a speckle field and forming a speckle field change image; the image acquisition module is used for acquiring a speckle field change image of one circle of the inner wall of the first section of circular ring shell under the irradiation of the light source; and the data storage and transmission module is used for storing and transmitting the speckle field image. The device is based on the optical measurement micro-deformation technology, speckle strain field change images on the periphery of the inner wall of the device shell are monitored through the miniature industrial camera, the measurement precision can reach the sub-pixel level, and in the high-temperature, high-pressure and high-ground-stress complex deep coal mine environment, the monitoring result can be stably and precisely output in real time.

The invention provides an underwater structure surface three-dimensional deformation measurement method under explosion impact based on a combination of a single high-speed camera and a beam splitter prism, and the method comprises the steps: S1, taking the beam splitter prism as an observation window of a waterproof cylinder, and packaging the high-speed camera into the waterproof cylinder to form an underwater integrated optical three-dimensional imaging system; s2, a blue light stroboscopic light source is adopted for illumination, and a blue light narrow-band filter is added in front of the camera for filtering; s3, making a random speckle field on the surface of the measured object, and increasing gray information of the surface of the structure; s4, recording a sequence deformation image of the structure surface speckle field under the explosion impact by using an underwater integrated optical three-dimensional imaging system, and segmenting the image into a left sequence image and a right sequence image along a center line; s5, respectively carrying out sub-pixel time sequence matching on the left sequence image and the right sequence image; and S6, establishing a mapping relation between pixel coordinates of points in the image and refracted rays in the space, and performing three-dimensional reconstruction and three-dimensional deformation calculation of three-dimensional points according to intersection of left and right rays in the space.

The invention discloses a precise measurement method for object surface out-of-plane displacement under high-frequency micro-vibration. The method comprises the following steps: exciting an object to generate high-frequency steady-state vibration through a vibration exciter, freezing a surface state at any vibration position of the object by adopting stroboscopic pulse laser with strictly same frequency as the vibration, and forming a shear speckle field by utilizing a Michelson interferometer comprising a piezoelectric ceramic driving phase-shifting mirror. The movement of the phase shift mirror and the acquisition of the high-speed camera as well as the actions of the stroboscopic laser and the vibration exciter are synchronously controlled through the double-signal controller, so that the accurate acquisition of multiple phase shift speckle interference images is realized. The image is processed based on a four-step phase shift algorithm, and the phase difference of the vibration position is calculated, so that the out-of-plane displacement derivative and the out-of-plane displacement in the shearing direction are calculated. According to the invention, the signal-to-noise ratio and the sensitivity of vibration measurement are obviously improved, and the method has full-field, non-contact and micro-nano displacement resolution capabilities, and is suitable for the fields of material nondestructive testing and structure health monitoring.

The application discloses a novel transparent soil model test device for simulating pipe-roof tunnel excavation and a test method thereof. The device comprises an excavation power system for pulling a temporary tunnel structure, a model tank, a pipe-roof model, a simulated tunnel structure, an acquisition system for acquiring speckle field dynamic deformation images and an image processing device for obtaining a three-dimensional deformation field of the transparent soil. The model tank is a T-shaped box structure, comprising a test area installed on a base and a connecting area suspended. The simulated tunnel structure is placed in the test area and comprises a hollow temporary tunnel structure with two open ends in an arch shape and a tunnel model in a solid arch shape arranged in the temporary tunnel structure. The pipe-roof model is an arch-shaped pipe row formed by bonding acrylic rods and arranged above the temporary tunnel structure. The application simulates an arch-shaped tunnel structure by an arch-shaped sleeve, can avoid soil disturbance, maintain tunnel section stability and truly restore the actual engineering state of tunnel excavation.

The application discloses a device and method for rapidly and continuously manufacturing speckle fields based on laser scanning, wherein the device comprises a control system, an executing mechanism, a scanning mechanism and a rotating mechanism; the rotating mechanism is connected with the control system through a signal transmission cable, and the control system controls start and stop of the rotating mechanism; the scanning mechanism is connected with the control system through a signal transmission cable, and the control system controls start and stop of the scanning mechanism; the executing mechanism is connected with the control system through a signal transmission cable, and the control system controls start and stop of the executing mechanism. The device and method for rapidly and continuously manufacturing speckle fields based on laser scanning are particularly suitable for automatically and continuously manufacturing speckle fields, and improve the precision and speed of speckle arrangement.

The invention provides a large-field-angle speckle projector and an imaging system.The large-field-angle speckle projector comprises at least two speckle projection units, and the light-emitting center axis directions of the light-emitting faces of the speckle projection units are not parallel; the speckle patterns emitted by the speckle projection units form an integral speckle field with an expanded field angle on a target field. Each speckle projection unit is of an independent structure; the at least two speckle projection units are designed in an outward-inclined mode or an inward-inclined mode. Or the large-view-field-angle speckle projector is of an integrated modular structure, each speckle projection unit at least comprises a light source and a micro-nano element, the light-emitting center axis directions of the light-emitting surfaces of the light sources are parallel to each other, or the light-emitting surfaces of the light sources are designed in an outwards-inclined mode or an inwards-inclined mode. By means of the structural design, large-field-angle speckle projection can be achieved, meanwhile, it is guaranteed that edge speckle patterns are small in distortion, edge speckle density is large, edge speckle energy is high, and the depth measurement requirement is met.

The invention belongs to the technical field of optical imaging, and discloses a non-intrusive imaging method and device penetrating through a dynamic scattering medium, and the method comprises the steps: controlling a preset coherent object light beam to irradiate an object to be imaged, and forming an object light field; collecting a speckle intensity image of a speckle field formed by an object light field penetrating through the preset dynamic scattering medium in a far-field region, wherein the far-field region is a region of the preset dynamic scattering medium penetrated by the object light field; based on a four-moment correlation function of the speckle intensity image, analyzing to obtain a far-field mutual dry function; according to a function relationship between the far-field mutual coherence function and the object light field autocorrelation function, analyzing to obtain an autocorrelation function of the object to be imaged; and based on a phase recovery algorithm, reconstructing an image of the to-be-imaged object through the autocorrelation function. According to the invention, view field limitation caused by dependence on an optical memory effect is avoided, imaging can be completed through single exposure, a data acquisition process is simplified, and adaptability to a dynamic scattering medium and imaging efficiency are improved.

The invention belongs to the technical field of optical measurement, and particularly relates to a laser speckle micro-nano displacement measurement device and method resistant to environmental interference. In the prior art, a scheme for measuring displacement by adopting single-light-path laser speckles is adopted, the measurement result is superposition of real displacement and displacement noise introduced by environmental disturbance, and the measurement result is easily interfered by external factors such as environmental vibration and air disturbance. Therefore, the signal-to-noise ratio is low and the precision and the stability are difficult to guarantee in the displacement measurement of micron and nanometer magnitudes. According to the device, laser serves as a light source and irradiates ground glass fixed to piezoelectric single crystal wafers of different sizes to generate a speckle field, a speckle image is analyzed through a two-dimensional digital image correlation algorithm, and then the infinitesimal displacement is obtained through calculation. For the influence of environmental disturbance (such as tremor) on the measurement precision, the introduced displacement noise and the minimum displacement to be measured are in the same magnitude, and a digital image correlation algorithm is difficult to reflect the influence in real time.

The invention discloses a space target transaction detection method and system based on laser dynamic speckles, and relates to the technical field of space target monitoring, and the method comprises the steps: constructing a space target model comprising a movable assembly; emitting a laser beam to the space target model, and collecting a dynamic speckle field formed by scattering; extracting a light intensity time domain signal based on the dynamic speckle field; extracting the characteristic frequency of the dynamic speckle field based on the light intensity time domain signal; establishing a correlation model for representing a corresponding relation between different motion states of the transaction component and the characteristic frequency of the dynamic speckle field; and comparing with the correlation model based on the characteristic frequency, and obtaining a target transaction judgment result based on a comparison result. Therefore, high-sensitivity and non-contact detection and identification on the tiny transaction of the space target component are realized.

This invention relates to the field of bridge displacement and stress field measurement technology, specifically to an existing bridge deflection and stress monitoring method based on digital image correlation technology. It includes deploying a speckle field on the surface of a key cross-section of the bridge to be monitored, setting up a high-speed camera to acquire time-series image sequences, processing the image data using a digital image correlation algorithm to calculate the full-field displacement field and full-field strain field of the key cross-section surface, verifying the full-field strain field to generate full-field deformation data, and using a physical driving model to invert the full-field deformation data into the stress distribution of the key cross-section, identifying stress concentration areas, and providing dynamic early warning based on a preset safety threshold. This invention provides full-field, dynamic observation of key areas of the bridge, avoiding the damage and long-term maintenance problems caused by drilling holes and attaching sensors to the structure. Theoretically, the measurement point density is only limited by the camera resolution, enabling seamless coverage of the entire monitoring area and ensuring that local damage is detected.

The invention discloses a transparent soil model test device for simulating shield synchronous grouting floating and a use method of the transparent soil model test device. The device comprises a transparent soil model box, a shield tunnel structure model, a synchronous grouting device, a base, a sliding rail, an industrial camera and a laser transmitter. The method comprises the following steps: 1) selecting a round cover and a negative ring cover which are matched; 2) filling transparent soil into the transparent soil model box until the transparent soil submerges the shield tunnel structure model; 3) installing a test device; 4) after standing for a period of time, starting a laser transmitter; 5) starting a synchronous grouting device to inject colored slurry into the steel pipe, pulling the shield body model out of the transparent soil model box by utilizing a drawing device, and continuously recording a speckle field formed in the transparent soil by the laser transmitter and the diffusion condition of the slurry by utilizing an industrial camera to obtain test simulation data; and 6) processing test simulation data by using a PIV technology to obtain a vector diagram of a transparent soil displacement field in the transparent soil model box and a diffusion diagram of slurry. The device is simple in structure, convenient to operate and high in reliability.

An apparatus for reducing speckle in holographic displays is disclosed. An illumination subsystem with one or more emitters and wavelength-selection elements provides multiple mutually incoherent spectral components at discrete wavelengths. A modulation stage receives the illumination, and display optics direct modulated light toward an image plane. Control circuitry selects at least two discrete wavelengths, computes wavelength-aware modulation patterns to decorrelate wavelength-dependent speckle fields, and directs the illumination subsystem to illuminate the modulation stage with the selected wavelengths effectively concurrently within an integration interval while applying the computed patterns. Resulting intensities from the concurrently illuminated, mutually incoherent wavelengths incoherently sum at the image plane to reduce speckle. The architecture can be integrated into near-eye display systems. Methods of use and manufacture are also disclosed.

The invention discloses a battery pole piece compaction density prediction method and device, equipment and a medium, and the method comprises the steps: firstly obtaining a speckle image of a battery pole piece, then detecting whether the surface of the speckle image accords with a preset condition, and if the surface of the speckle image accords with the preset condition, carrying out the special extraction of the speckle image of the battery pole piece, and acquiring multi-dimensional texture features of the speckle image, inputting the multi-dimensional texture features of the speckle image into the trained regression model, and outputting a predicted value of the compaction density of the battery pole piece. By analyzing the spatial statistical characteristics of the speckle field formed on the surface of the pole piece irradiated by the laser, the accumulation state of the particles in the pole piece and the pore structure are directly associated, and accurate evaluation of the compaction density can be realized without physical contact with the sample.

An imaging method includes: (I) simultaneously illuminating a scene with a first (second) diverging wave originating from a first (second) location and modulated with a first (second) shift-and-add-qualifying-code. A scatterer that scatters the first (second) diverging wave as a first (second) speckle. (II) Detecting, with a receiver, an interference signal, produced from interference between the speckle fields, and including a code temporally shifted with respect to the first SAA-code by a large-scale time-shift. (III) Circulantly correlating the interference signal with a reference SAA-code to generate a correlation signal. (IV) Determining the time-difference-of-arrival from the large-scale time-shift. (V) Determining a location of the scatterer by: determining, from the time-difference-of-arrival, a hyperbolic contour that locates the scatterer angularly; and determining, from one of (i) a small-scale time-shift of a peak of the correlation signal and (ii) a ranging delay, an elliptical contour that locates a range of the scatterer from the receiver.

The application provides a low-noise speckle interferometry system and method based on a spatial light modulator, relates to the technical field of speckle interferometry, and comprises a laser, a light splitting prism one and an imaging element; a laser beam emitted by the laser is split into transmitted light and reflected light by the light splitting prism one; part of the transmitted light is reflected by a light splitting prism three and then irradiated on the imaging element as reference light; part of the reflected light sequentially passes through a linear polarizer and a half-wave plate, is modulated by a spatial light modulator assembly, is irradiated on a light splitting prism four, is reflected to a measured object surface to occur diffuse reflection, and slow light is obtained; the speckle interferometry system modulates object light by using the spatial light modulator assembly, makes the emitted light modulated by the spatial light modulator assembly irradiate the measured object at multiple illumination angles, forms independent speckle fields on a target surface of the imaging element, and can effectively suppress speckle de-correlation noise after multiple measurement superposition, and then the accuracy of subsequent measurement results is improved.

The application discloses a kind of metro tunnel mine method excavation visual test system, comprising: installation in the combined model box of optical platform: wherein with visual filling material to simulate the surrounding rock of subway tunnel;Tunnel excavation module utilizes isolation material to divide internal interface into multiple cavern areas, to form the tunnel model of predetermined plan excavation, each cavern area is filled with visible, meltable filling, and is buried with conductive hot melting device to simulate the excavation of tunnel;Support system is the anchor rod simulation device of pre-setting in surrounding rock material;Loading device includes stress loading unit for applying load to simulate the original stress of tunnel around and pressure sensor for monitoring load size;Laser instrument is used to emit laser beam to generate speckle field;Imaging device is used to take speckle field image;There are image recognition and interpretation module (special image analysis tool GEO-PIV based on matlab development). The application can realize the whole process visualization of tunnel any part excavation.

This invention discloses a visual transparent soil model test device and method for studying embankment deformation, belonging to the field of highway engineering test technology. It solves the problem that existing model test methods cannot visually display the internal deformation of embankments under load, thus hindering the analysis of foundation deformation patterns. Specifically, it includes a model box located at the bottom of a reaction frame, with an actuator mounted on top of the reaction frame. The model box is filled with soft soil material, and a loading plate is laid on top of the soft soil material. The bottom of the actuator contacts the loading plate. In this invention, the actuator applies a sinusoidal load to the soft soil material inside the model box, simulating traffic loads on the embankment. An industrial camera is used to capture real-time images of the changes in the speckle field of the soft soil beneath the embankment and within the embankment during the application of traffic loads, thereby analyzing the deformation mechanism of highway embankments in complex mountainous terrain. The analysis results are accurate and reliable, providing data support for the design and construction of highway subgrades in mountainous areas.

The present application relates to a kind of microscopic speckle interferometry full-field imaging detection device, including excitation pulse laser, probe pulse laser and digital pulse delay unit.Pulse laser acts on the heat generated by material surface, thereby exciting ultrasonic pulse signal.Ultrasonic carries the defect structure information of material.On the other hand, light shear speckle interferometry technology uses the speckle field of object surface to be imaged on the surface of digital camera image sensor after passing through shear device.When the measured target is loaded by ultrasonic wave and the surface is slightly deformed, the phase distribution of shear speckle interferogram also changes.The two shear speckle interferograms obtained before and after deformation are directly subtracted, and the light intensity difference or phase difference pattern can be obtained.The distribution of stripe is related to the deformation of measured target, and the surface of measured target can be analyzed according to this, so as to measure the off-plane displacement of object surface caused by internal defect under the condition of ultrasonic wave loading.

The invention provides a multi-mode optical fiber speckle imaging and distance measuring system and method, and relates to the technical field of imaging and distance measuring, and the system comprises an optical fiber coupler which is used for coupling an illumination light field emitted by a coherent light source into a multi-mode optical fiber probe, and enabling the illumination light field to irradiate a measured target through the multi-mode optical fiber probe; the multi-mode optical fiber probe is used for receiving the signal light field reflected by the measured target into the multi-mode optical fiber and outputting a speckle field through the multi-mode optical fiber; the area array image sensor is used for sending the speckle field to the data image processing module; and the data image processing module is used for calculating the detection distance of the detected target and reconstructing the image information of the detected target based on the speckle field output by the multimode optical fiber. According to the multimode optical fiber speckle imaging and distance measuring system and method, a lens-free illumination and detection integrated structure is adopted, the integration level and flexibility of the system are remarkably improved, and meanwhile high-precision imaging and distance detection are achieved through a speckle light field of compressed sampling.

The application discloses a kind of full-field dynamic three-dimensional deformation measurement method and system based on polarization multiplexing, by the polarization state of object light and reference light is adjusted to circularly polarized light and 45 ° linearly polarized light respectively, polarization CCD is used, the synchronous recording of speckle field and speckle interference phase shift field before and after the three-dimensional deformation of measured object occurs is realized.The speckle interference phase shift map recorded by the pixel of polarization direction 0 and 90 on polarization CCD is used to restore off-plane deformation, and the speckle map recorded by the pixel of polarization direction 135 is used to carry out DIC calculation and restore in-plane deformation.The problems that direct speckle map and interference phase shift map cannot be recorded synchronously and dynamic measurement demand is not easy to meet in the related technology of three-dimensional deformation dynamic measurement combining DSPI and DIC are solved.

This invention relates to the fields of medical ultrasound simulation, medical image processing, and computer-aided medical teaching and training. Specifically, it relates to a real-time ultrasound simulation method based on echo event maps and spatiotemporal coherent speckle field reconstruction. This invention constructs a three-dimensional tissue acoustic parameter field, establishes a probe transmit / receive beam model and echo event map, and physically models boundary echoes and volume scattering echoes respectively. It introduces a spatiotemporal coherent speckle field to constrain the continuous evolution of speckle, eliminating speckle jumps and flicker during continuous scanning. It simulates shadows and post-enhancement effects through an artifact modulation model, and generates highly realistic ultrasound images through RF signal synthesis, system response processing, logarithmic compression, and scan transformation. This effectively meets the high-simulation requirements of medical ultrasound teaching and skills training.

A coal rock dynamic disaster prediction method based on multivariate image information belongs to the field of coal mine coal rock dynamic disaster prediction, fuses sound information and visual information, extracts coal mine underground surrounding rock characteristics, and predicts the occurrence of dynamic disasters in combination with a machine learning model. The method mainly comprises the following steps: collecting sound signals in a field key observation area, making an artificial speckle field, extracting spectrogram information, and extracting digital speckle information; establishing a data set and a coal rock dynamic disaster prediction model based on multivariate image information, and training the model; and extracting a spectrogram and a speckle image of an on-site key observation area, calculating entropy, mean sum, variance sum and angular second moment of the spectrogram and a deformation field non-uniform statistical index SW value of the speckle image, and sending the values into the established coal rock dynamic disaster prediction model based on the multivariate image information for prediction.

The invention relates to the technical field of microscopic optical measurement mechanics, and discloses a method for measuring bending deformation of a micron-sized multilayer composite film, which comprises the following steps of: activating the surface layer of an observation section, grafting nano-sized optical tracer particles in situ by using chemical bonding, and constructing an anti-slip three-dimensional speckle field; the method comprises the following steps of: performing continuous layer scanning in a depth direction under a micron-sized view field by utilizing a laser scanning confocal microscope aiming at the limit of extremely shallow depth of field of high-magnification imaging to obtain three-dimensional volume data with a high signal-to-noise ratio; a three-dimensional full displacement field is obtained by using a three-dimensional body feature tracking algorithm, and then a three-dimensional strain field is solved. The system provided by the invention solves the problems of difficult speckle making of a micron-sized narrow section, difficult observation of local wrinkle fluctuation and difficult calculation caused by plane hypothesis failure, and realizes accurate measurement and characterization of three-dimensional deformation of each single layer and interface of the multilayer composite film.

The invention relates to a correlated imaging system based on compressed sensing and deep learning in a complex environment, and the system comprises a light source transmitting module which is used for transmitting a light source with a target wavelength; the debugging digital micromirror module is used for projecting speckles on the target image by the light source and reflecting the light source to the atmospheric turbulence and aerosol simulation module; the atmospheric turbulence and aerosol simulation module is used for simulating an atmospheric turbulence environment and an aerosol environment and projecting an output light beam to a site; and the imaging receiving module is used for acquiring the light field containing the target information, calculating the transformation of the light field, obtaining the spectrum distribution of the speckle fields, calculating an intensity correlation function between different speckle fields, and reconstructing a target image. According to the method, powerful support is provided for development and application of the correlated imaging technology by researching the performance problem of correlated imaging in a complex environment.

The application discloses a system and method for three-dimensional reconstruction of object shape and deformation by using laser speckle, and belongs to the field of optical measurement and three-dimensional imaging. The system forms a random and uniform speckle field on the surface of an object through a speckle laser emission module, synchronously collects speckle images by using a multi-view high-speed camera, obtains accurate parameters after camera calibration, tracks and matches speckle feature points by using a three-dimensional PTV algorithm, and solves three-dimensional coordinates and dynamic displacement vectors of the object. The technology does not need to manually mark feature points, realizes contactless and integrated measurement, has high precision and high time resolution at a sub-pixel level, can capture nanoscale tiny deformation and complex curved surface dynamic processes, has strong anti-interference ability, is suitable for industrial detection, structure health monitoring, experimental mechanics measurement and other scenes, effectively solves the problems of separation of static and dynamic measurement, complicated operation and narrow application range of traditional technologies, and improves measurement efficiency and data reliability.

The application discloses an underwater multi-state polarization differential correlation imaging device and method, relates to the technical field of underwater target imaging detection, and comprises a light source unit, a light beam modulation unit, a polarization regulation unit, a detection unit, a synchronous control unit and a data processing unit. The light source unit is used for outputting an initial light beam. The light beam modulation unit is used for phase modulation on the initial light beam, generating vortex light beams without diffraction characteristics and a reference speckle field. The polarization regulation unit is used for switching the reflected light beams reflected by a target into light beams with multiple different polarization states. The detection unit is used for collecting light signals corresponding to the light beams with different polarization states. The synchronous control unit is used for synchronously controlling the polarization regulation unit and the detection unit. The data processing unit is used for correlation calculation and image fusion by using a polarization differential correlation algorithm according to the reference speckle field and the light signals, so as to obtain a final imaging result. The application improves the accuracy of target identification in an underwater environment and improves the correlation imaging quality.

The application provides a three-dimensional mining stress monitoring device and method based on monitoring micro-deformation of a drill hole, and belongs to the technical field of mining stress monitoring in mining engineering, wherein the device comprises a three-dimensional mining stress sensor, the three-dimensional mining stress sensor comprises an information tracking module, an image sensing and capturing module and a data storage and transmission module; the information tracking module is used for mapping information of a speckle field on an inner wall of the drill hole to the monitoring device; the image sensing and capturing module is used for acquiring image information of the speckle field on the inner wall of the drill hole mapped to the monitoring device; and the data storage and transmission module is used for saving and transmitting the image information of the speckle field on the inner wall of the drill hole. The device solves the shortcoming that traditional monitoring equipment cannot be coupled with a rock mass to achieve coordinated deformation, the measurement precision can reach a sub-pixel level by monitoring the movement of pixel points on the speckle field of the drill hole, and the obtained monitoring result has higher reliability and precision.

The invention provides a three-dimensional mining-induced stress monitoring device and method based on monitoring of drill hole micro-deformation, and belongs to the technical field of mining-induced stress monitoring of mining engineering, the device comprises a three-dimensional mining-induced stress sensor, the three-dimensional mining-induced stress sensor comprises an information tracking module, an image sensing and capturing module and a data storage and transmission module; the information tracking module is used for mapping the information of the speckle field on the inner wall of the drill hole into the monitoring device; the image sensing and capturing module is used for acquiring image information of the speckle field of the inner wall of the drill hole mapped into the monitoring device; and the data storage and transmission module is used for storing and transmitting the image information of the speckle field on the inner wall of the drill hole. According to the device, the defect that traditional monitoring equipment cannot be coupled with the rock mass to achieve coordinated deformation is overcome, due to the fact that movement of pixel points on a borehole speckle field is monitored, the measurement precision can reach the sub-pixel level, and the credibility and precision of a result obtained through monitoring are higher.

The invention discloses an underwater multi-configuration polarization difference correlation imaging device and method, and relates to the technical field of underwater target object imaging detection, and the device comprises a light source unit, a light beam modulation unit, a polarization regulation and control unit, a detection unit, a synchronous control unit and a data processing unit. The light source unit outputs initial light beams; the light beam modulation unit is used for performing phase modulation on the initial light beam to generate a vortex light beam without diffraction characteristics and a reference speckle field; the polarization regulation and control unit is used for switching reflected light beams reflected by the target object into multiple groups of light beams in different polarization states; the detection unit is used for collecting optical signals corresponding to light beams in different polarization states; the synchronous control unit is used for synchronously controlling the polarization regulation and control unit and the detection unit; and the data processing unit is used for performing correlation calculation and image fusion by adopting a polarization difference correlation algorithm according to the reference speckle field and the optical signal to obtain a final imaging result. The accuracy of target object recognition in the underwater environment is improved, and the correlated imaging quality is improved.

The application provides a dynamic encryption imaging method and device based on orbital angular momentum speckle, and the method comprises the following steps: step 1, generating an initial Gaussian light beam output by a coherent light source, and adjusting the polarization state of the initial Gaussian light beam through a polarization control unit, and adjusting the aperture of the light beam through an expansion optical system; step 2, generating an orbital angular momentum vortex light beam corresponding to a topological charge number; step 3, forming an orbital angular momentum speckle field corresponding to the topological charge number one by one, and taking the orbital angular momentum speckle field as a dynamic encryption key; step 4, continuously illuminating a dynamic target and realizing information multiplexing coding; step 5, obtaining an encrypted intensity image carrying multiple frames of dynamic information; and step 6, outputting multiple frames of dynamic imaging results. The application realizes efficient optical encryption imaging of a dynamic scene under single-exposure conditions, and has the technical effects of large key space, strong controllability, simple system structure, strong anti-interference ability and the like.