105 results about "Speckle field" patented technology

The invention discloses a random scattering optical imaging system and a random scattering optical imaging method based on sparse representation. The imaging system comprises a light source (1), a spatial filter (2), an aperture diaphragm (3), a collimating lens (4), a reflector (5), a spatial light modulator (6), a random scattering medium (7), a lens (8), a detector array (9), and a main control computer (10). Light emitted by the light source enters the spatial light modulator via the reflector after passing through the spatial filter, the aperture diaphragm and the collimating lens. The main control computer loads an imaging target on the spatial light modulator, so that light emitted from the spatial light modulator and carrying target information forms a coding speckle field image on the detector array after passing through the random scattering medium and the lens, and the coding speckle field image is transmitted to the main control computer. The main control computer decodes and reconstructs the coding speckle field image and removes background noise to obtain a target image. The random scattering optical imaging system of the invention has a simple structure, good real-time performance and high noise resistance. The system and the method of the invention can be used for random scattering high-speed imaging in a noise environment in the laboratory.

The invention discloses a welding deformation real-time detection system. The welding deformation real-time detection system is characterized by comprising a CCD camera (4), an environment light source (5), a detection module and a control module, the CCD camera (4) is used for generating a speckle field and forming speckle images on the surface of an irradiated welding workpiece, and then collecting the speckle images on all the stages of welding of the surface of the welding workpiece, the environment light source (5) is used for providing lighting of the surrounding of the welding workpiece when the speckle images are collected, the detection module is used for processing the collected speckle images, and recognizing three-dimensional coordinate changes of a deformation point, on the surface of the welding workpiece, on the speckle images according to the speckle images of all the stages so as to obtain a three-dimensional displacement field and a strain field of the surface of the welding workpiece, and the control module is used for providing electric power support for the CCD camera and having control over the image collection process. According to a detection method of the welding deformation real-time detection system, the cost is reduced, efficiency and accuracy are improved, and the great actual use value, and the economic and social benefits are achieved.

The e invention relates to a power soil arch model testing system and method based on a transparent soil technology. The testing system comprises a reaction frame, a loading device, a model bracket, a vertical sliding screw, a worm gear case body, a horizontal connecting shaft, an electric motor, a laser emitter and measurement equipment; fixed blocks and movable blocks are mounted at the bottom of a model groove; the model groove can perform relative displacement to the fixed blocks by shifting the movable blocks after being provided with transparent soil, and forms stable soil arches in the transparent soil; the loading device is mounted on the reaction frame, so as to perform power loading and simulate the influence on the soil arches by power load. The method comprises the steps of determining the sizes and quantity of required fixed blocks and movable blocks, mounting and sealing the fixed blocks and movable blocks, mounting the electric motor, the horizontal connecting shaft, the vertical sliding screw and the worm gear case body, drawing the movable blocks to move, simulating situations of positive and negative soil arches and different quantity of soil arches, fixing the movable blocks after the soil arches are formed, performing power loading through the loading device, shooting laser speckle field through a high-speed camera during testing, and analyzing rules of the formation of the soil arches and evolution of the soil arches under dynamic load.

The invention provides a quick digital image correlation measurement method based on stochastic parallel gradient descent optimization technology, comprising the following steps of comprehensively considering related parameters such as displacement, differential coefficient and the like of any one point in a speckle field of an object to be measured; and utilizing the stochastic parallel optimization technology to realize quick digital image correlation measurement. In the method, by adopting stochastic parallel disturbance on a deformation parameter, the correlation coefficient is convergentto a global unique extremum, thus obtaining the deformation parameter. The method has a simple principle, can be realized easily, is a DIC (digital image correlation) measurement method with totally new concept, can realize the aim of quickly measuring DIC with high precision and high reliability, and is expected to realize the real-time online measurement on the DIC.

A high resolution 3-D holographic camera. A reference spot on a target is illuminated by three spatially separated beamlets (simultaneously produced from a single laser beam), producing a lateral shear of a wavefront on the target. The camera measures the resulting reflected speckle intensity pattern which are related the gradient of the interfered complex fields. At the same time a flood beam illuminates the entire target and reflected speckle is also recorded by the same camera to provide the necessary object spatial frequencies. The illumination patterns are sequenced in time, stepping through offset phase shifts to provide data necessary to reconstruct an image of the target from the recorded reflected light. The reference spot phase and amplitude are then reconstructed, and the reference spot's complex field is then digitally interfered with the flood illuminated speckle field by use of a special algorithm. In order to obtain a high resolution 3D image of the target, a second measurement is acquired with the laser beam slightly shifted in frequency to second color.

The invention discloses an apparatus for generating a controllable super-Rayleigh speckle field and a method for generating the same. The generating apparatus includes a continuous wave laser, a computer I and a computer II. Along the progressing direction of a light beam of the continuous wave laser there is successively provided with an adjustable laser attenuator, a pinhole filter, a lens, a polarizer I and a beam splitter. From the beam splitter, the light beams is divided into two light beams which progress along two different directions, and along the progressing direction of one light beam there is provided with a reflecting spatial light modulator, and along the progressing direction of the other light beam there is provided with an analyzer I, a diaphragm I, a polarizer II, a transmission type spatial light modulator, an analyzer II, a diaphragm II, a Fourier lens and a CCD camera, wherein the reflex spatial light modulator is connected to the CCD camera and the computer I, and the transmission-type spatial light modulator and the computer II are connected. According to the invention, the values of an exponential factor S and an angular index m are changed to obtain a target super-Rayleigh speckle field, so that the super-Rayleigh speckle field which has a controllable speckle size and contrast ratio is obtained.

The invention discloses a deformation and slope synchronous measurement device and method based on digital speckle interferometry. Light from a laser is divided into a first beam of light and a second beam of light by a beam splitter prism. The first beam of light is reflected onto an imaging target surface of a monochrome CCD camera by another beam splitter prism, thereby forming a reference optical path. The second beam of light is reflected to a surface of a measured object via a plane mirror, thereby forming a laser speckle field. The monochrome CCD camera receives the laser speckle field at the same time from two directions which are symmetric to an optical axis, so that two object optical paths are formed. By switching the on/off state of the reference optical path and the object optical path, a digital speckle interference optical path and a shear digital speckle interference optical path for synchronous measurement are formed, a speckle interference fringe phase and a shear speckle interference fringe phase are extracted, and the surface deformation and slope of the measured object are measured. The invention realizes synchronous and independent measurement of deformation and slope information of the measured object, without repeated loading and later separation. The phase shift technology is adopted, thereby improving the measurement accuracy. The dual speckle interference optical paths with adjustable measurement sensitivity and object-light sharing are constructed, so the whole structure of the system is simple and compact.

The invention relates to an electronic speckle-interference digital-compensating method with simple operation and higher precision and a system thereof. The method comprises the following steps of: 1) fixing a measured object onto a loading device, acquiring four four-step phase-shifting speckle images before loading, and moving a plane mirror through a phase shifter to change the optical-path difference of reference light and object light to realize phase shifting; 2) after loading the measured object, reacquiring four four-step phase-shifting speckle images by a method which is similar to the step 1); 3) calculating the corresponding in-plane two-dimensional displacement of a first phase-shifting speckle image before and after deformation by a two-dimensional digital-speckle related method; 4) carrying out reverse displacement for mismatched speckle-field images before and after deformation by a digital operation method to realize the realignment of speckle fields before and after deformation; and 5) calculating the phase difference corresponding to the deformation before and after loading by a direct phase-difference solving method.

The invention relates to a device and a method for measuring particulate motion of turbid media by using a dynamic speckle method. The device comprises a laser beam shaping contracting part, a forward scattering speckle field measuring part, a backward scattering speckle field measuring part, and a computer control and processing system. The method comprises the following steps: utilizing the device to record a forward scattering speckle field and a backward scattering speckle field generated by the particulate motion of turbid media and store the fields into the computer; according to the particle light scattering theory, choosing the forward scattering speckle field or backward scattering speckle field data; and analyzing the motion characteristic of the particulate, by utilizing a speckle chart characteristic value. The method is characterized by real time, dynamic and accuracy and can be widely applied to the fields such as medicaments, biology, life science, and the like.

The invention relates to a soldered joint stress concentration testing device and stress concentration testing method based on the laser speckle technology. The soldered joint stress concentration testing device and stress concentration testing method based on the laser speckle technology solves the problems that according to an existing laser speckle technology, a process for regulation of a light path is cockamamie and complex, flexibility is poor, and the existing laser speckle technology can be only used for laboratory measurement analysis and cannot carry out on-site measurement on actual components with large sizes and complex space shapes. Two collimation beam expanding mirrors are adopted in the soldered joint stress concentration testing device and stress concentration testing method and are arranged above a tested piece symmetrically, two beams of collimation light can be obtained, a digital CCD camera is used for collecting two speckle field images loaded before and after deformation respectively, model reduction processing is carried out on the two speckle field images through a computer, and then a bar chart reflecting a deformation condition can be obtained to further achieve testing and analysis of a stress concentration state. The soldered joint stress concentration testing device and stress concentration testing method is applied to crossing fields of materials science, optics and mechanics.

The invention discloses a visual saturated dynamic water-bearing sand bed permeation grouting test device and method. The visual saturated dynamic water-bearing sand bed permeation grouting test device comprises a visual model box, a grouting pump, a sprinkling plate, an oil pump, a constant head water tank, a laser sheet source transmitter, an industrial camera and a data collection system, wherein slurry is injected into the visual model box by the grouting pump through a slurry delivery pipe; openings are uniformly formed in a bottom plate; a layer of filter net covers the bottom plate; an oil receiving tank is arranged at the bottom of the visual model box and connected with the oil pump through an oil delivery pipe; the oil pump is connected with the constant head water tank; a locating water tank is also connected with the sprinkling plate connected to the top of the visual model box through the oil delivery pipe; the laser sheet source transmitter is arranged at one side of the visual model box; laser light emitted from the laser sheet source transmitter penetrates through transparent soil through the visual model box to form a uniform speckle field; the shooting direction of the industrial camera is located in a normal direction of a laser plane; and the camera is connected with the data collection system and records the change of the speckle field in real time.

The invention provides a digital double-micro speckle measuring method for strain. The invention relates to the measuring method for the stress and the strain of a structure, in particular to the measuring method for the stain with application of the photoelectron technology. The CCD with a micro-lens is arranged on a fixed platform while two CCDs serve as a group in the invention; when in measuring, a speckle field is manufactured on the surface of the measured object and the speckle images of the measured object in the scale distance between two points before and after being loaded are collected by the double-CCD synchronously and then are operated by the related processing software after being transmitted into a PC machine, at last, the mechanics parameter of the measured object can be obtained. The invention has short detection period, low consumption of resources, low detection cost, good economic benefit, easy interpretation and convenient and wide application. Meanwhile, the method can be used for detecting and evaluating the safety performance of other large buildings, such as houses, large dams, etc.

Disclosed is an obtaining method of measurement matrixes of a compression spectral imaging system based on random wave front phase modulation. When the method is used for obtaining the measurement matrixes of the compression spectral imaging system based on random wave front phase modulation, a broadband hot light source, a spectral filtering device, a pinhole diaphragm and a magnification imaging lens need to be added in a light path of the system. According to the obtaining method, the translation invariance of the local space of the compression spectral imaging system based on the random wave front phase modulation is used, and the measurement matrixes of the system are obtained through low measuring frequency; a high-contrast-ratio speckle field is obtained through the method that speckle light intensity distribution on an original detection face is magnified and imaged onto a detection face, and the signal to noise ratio of the measurement matrixes is increased.

The invention provides a transparent soil model test device for simulating lateral soil movement and a test method for the transparent soil model test device. The transparent soil model test device comprises a transparent model box which can be fixed to an optical table, a T-shaped block and a loading block. The whole transparent model box is a rectangular box body. The circumferential wall of one side of the rectangular box body is provided with a rectangular notch. The T-shaped block is embedded in the notch side of the transparent model box. An oil pressure jack, two industrial cameras and two laser transmitters are arranged outside the transparent model box. During testing, a test model pile is buried in transparent soil. The loading block is abutted against a web part by the oil pressure jack. The oil pressure jack applies displacement to the loading block in a graded mode. The two laser transmitters transmit lasers. Two transparent soil speckle fields are formed in the transparent soil. The industrial cameras record the change of the transparent soil speckle fields. The test method for the transparent soil model test device comprises the steps of mold making, transparent soil preparation, graded loading and the like. The transparent soil model test device is small in size, the system is arranged reasonably, and test operation is convenient.

The invention discloses a preparation method for transparent clay in an energy pile model test, application and a testing device. The transparent clay is prepared from Carbopol Ultrez 10 polymer and a nanometer material serving as a speckle field of the transparent clay, the transparent clay is fed into a transparent model tank in a layered mode with transparent sandy soil to form a testing soil layer, a plurality of CCD cameras are arranged with the transparent model tank as the circle center, the CCD cameras are connected with a computer to send images shot by the CCD cameras to the computer to perform image processing and analysis and are used for exploring energy pile soil disturbance under hot-cold circulation and pile top load action, energy pile bearing capacity change and a pile periphery soil body temperature change law. The preparation method for transparent clay in the energy pile model test, the application and the testing device disclosed by the invention can effectively solve the problem about an energy pile-soil heat transfer mechanism and load transfer mechanism in soft clay cannot be visually researched, are simple to operate, economical and practical, have obvious testing effects and have wide application prospect.

The invention discloses a method and a device for simulating fissure expansion of hydraulic fracturing in plane distribution, the method comprises the following steps: firstly, the front surface and the rear surface of a specimen are clamped with two pieces of transparent glass steel, fastening bolts are tightened, the upper surface and the lower surface of the specimen are clamped tightly with metal loading plates, and a constant voltage and constant current pump is connected with a stainless steel sleeve part in the specimen; the constant voltage and constant current pump is opened for injection of a liquid into the specimen, the specimen is gradually completely broken, in the loading process, and continuously changing pictures of the speckle field of the surface of the specimen are obtained by a high-speed camera, and stored in a computer; and change rules of the displacement field and the strain field of the surface of the specimen can be obtained by analysis software in a load application process. Based on digital speckle expansion technique and through the analysis of the change rules of the displacement field and the strain field, the interaction mechanism between artificial and natural fractures in the artificial crack propagation process and after intersection of the artificial and natural fractures can be obtained, and a foundation is laid for studies on formation mechanism of shale reservoir fracture network cracks.

The invention provides an associated imaging spectroscopic camera based on non-Rayleigh speckle field and an imaging method thereof. The device comprises a front imaging mirror, a beam splitter, a band pass filter, a monitoring detector, a polarizer, a beam splitter, a spatial light modulator, an area array detector and a computer. According to the method, the reversible characteristics of an optical path are used, the non-Rayleigh speckle field can be generated under the condition of no lens, and the non-Rayleigh speckle field is applied to a correlation imaging spectroscopic camera based oncompressed sensing, wherein the imaging using a super Rayleigh speckle field can improve the quality and resolution of a reconstructed image under a low signal-to-noise ratio condition.

The invention provides an optical angle measuring device and an angle measuring method. The optical angle measuring device comprises two light sources, a dispersion prism, a semi-transflective mirror, a photoelectric detector, an image processor, a measured object and a first lens, wherein the two light sources are arranged along the optical axis of the optical angle measuring device; a rough sample plate is arranged on the measured object; light beams emitted by the two light sources pass through the dispersion prism and are combined into coherent light by the dispersion prism; the dispersion prism, the semi-transflective mirror and the measured object are arranged in turn; coherent light generated by the dispersion prism passes through the semi-transflective mirror and emits on the surface of the rough sample plate which is arranged on the measured object so as to be scattered; scattered light is reflected by the semi-transflective mirror and passes through the first lens in another transmission direction; scattered light focused by the first lens is acquired by the photoelectric detector on the focal plane of the first lens; and an acquired multi-dispersion speckle field light intensity distributed image is transmitted to the image processor by the photoelectric detector for image processing.

The invention relates to a stress testing device and stress concentration testing method based on the speckle interference principle. The stress testing device and stress concentration testing method based on the speckle interference principle solves the problems that according to an existing laser speckle technology, a process for regulation a light path is cockamamie and complex, flexibility is poor, and the existing laser speckle technology can be only used for laboratory measurement analysis and cannot carry out on-site measurement on actual components with large sizes and complex space shapes. Four collimation beam expanding mirrors are adopted in the stress testing device and stress concentration testing method and are arranged on the surface of a tested piece symmetrically, two beams of collimation parallel laser are obtained, a digital CCD camera is used for collecting four speckle field images loaded before and after deformation respectively through control of on-off of four paths of light, and the computer digital picture processing technique is adopted to obtain displacement distribution in two orthogonal directions to further obtain distributed information of stress states of a tested area. The stress testing device and stress concentration testing method is applied to crossing fields of materials science, optics and mechanics.

The invention provides a transparent soil model test device for simulating tunnel excavation deformation and a test method. The device comprises a transparent model box which can be fixed on an optical platform, a thin-wall rubber cylinder and a drain pipe. The transparent model box adopts a box body formed by splicing plates. Circular openings are formed in the two side walls of the box body. Anopening is formed in the edge of the bottom surface on one side of the thin-wall rubber cylinder. The thin-wall rubber cylinder penetrates through the openings in the transparent model box. A valve isarranged on the drain pipe. The drain pipe is connected to the opening in the thin-wall rubber cylinder. Two industrial cameras and two laser emitters are arranged outside the transparent model box.The valve on the drain pipe is opened during testing, and water in the thin-wall rubber cylinder is drained into a flash with scales separately. Laser emitted by the two laser emitters forms two transparent soil speckle fields in transparent soil. The industrial cameras records changes of the transparent soil speckle fields.

Disclosed is a double-rotation optical wedge space phase shift method used for cutting speckle interference. The double-rotation optical wedge space phase shift method used for cutting speckle interference is designed aiming at the dynamic measurement of plane deformation in the speckle interference measurement. Double holes are added in an imaging optical path, carrier frequency is introduced, thus the space phase shift requirements required by the phase extracting algorithm are met. A gap between the two holes is changed, the distance between adjusting imaging lens and an image plane is adjusted, thus control of size of phase shit quantity of the space can be achieved. Rotable and adjustable double optical wedges are arranged on the position of any one hole of the double holes. One beam of light ray of two beams of light rays passing the double holes deflects, thus two speckle fields on the image plane are caused to be mutually cut. A whole refraction angle of combining the double optical wedges is changed by revolving one of the optical wedges or by the relative revolving of the two optical wedges, thus regulation of the size of the cutting quantity is achieved.

The present invention discloses an optimization preparation method of an experiment speckle field. The method comprises: selecting an optimal digital speckle field according to the computer speckle design program and the speckle quality assessment criterion, employing indirect preparation method such as transfer print (hydrographics transfer printing, heat transfer printing and the like), laser cutting, silk screen printing, photosensitive stamp, hollow template to transfer the integrated information of the digital speckle field to the surface of an object to be measured for providing high-precision and good-consistency speckle field for digital image relation measurement. Through optimization selection and direct transferring of the digital speckle field generated by the computer, the problems are solved that the digital image relation method measurement precision is undetermined caused by unstable quality of the speckle field and the traditional spraying making random speckle field method and others depend on the technicians' operation skill levels so as to ensure the reliability of the digital image relation method in the scientific research and the real engineering measurement.