CN202748011U - Three-dimensional deformation measurement system with speckle correlation and speckle interference combined - Google Patents

Abstract

The utility model relates to a three-dimensional deformation measurement system with speckle correlation and speckle interference combined. The three-dimensional deformation measurement system comprises a laser device. Laser emitted by the laser device is subjected to beam expanding and passes through a half transparent and half reflecting mirror, and then respectively shines on an object to be tested and a reference object plane. The images of the object to be tested and the reference object plane are generated on a charge coupled device (CCD) video camera through the half transparent and half reflecting mirror via an imaging lens at the same time. The half transparent and half reflecting mirror is placed obliquely relative to incident rays in an angle of 45 degrees. When a reference light path exists, object plane speckle and reference plane speckle on a target plane of the CCD video camera are in mutual interference so that an interference speckle image is formed, an off-plane displacement component is measured, the reference object light path is removed, the speckle image on the object plane is collected, two speckle images before deformation and after deformation are used, and two components of in-plane displacement are worked out by using speckle correlation operation. According to the three-dimensional deformation measurement system, a typical numerical speckle light path which is sensitive to off-plane displacement is used, in-plane displacement measurement of the object by speckle correlation and off-plane displacement measurement by speckle interference are achieved, three-dimensional displacement measurement is achieved, and the three-dimensional deformation measurement system has the advantages of being simple in light path, simple and quick in operation and data processing.

Description

The measurement system for three-dimensional deformation that speckle is relevant and speckle interference combines

Technical field

The utility model relates to a kind of measurement system for three-dimensional deformation, relates in particular to the measurement system for three-dimensional deformation that a kind of speckle is relevant and speckle interference combines.

Background technology

By the digital speckle correlation method (Digital Speckle Correlation Method, DSCM) that the people such as I Yamaguchi, W.H.Peters and W.F.Ranson propose measure in real time at the mechanics of materials, fracturing mechanics, biomechanics, scene, the measurement of microscale deformation field, Electronic Packaging and numerous applications such as dynamic displacement and deformation test have all showed its applicability and superiority.The digital speckle correlation technology by record before and after the deformation of body image and displacement and the distortion of using certain image correlation searching algorithm to draw object, have that principle is simple, light path simple, noncontact, measurement environment required the advantages such as low.In recent years, the mathematical theory that some are modern and mathematical method are introduced in the method gradually, and the raising progressively of its measuring accuracy for example uses the sub-pix searching algorithm can obtain Displacement.The sub-pix algorithm has a variety of, mainly contains related coefficient fitting process, Newton.Raphson (N-R) process of iteration, based on method of gradient etc.Compare with additive method, gradient method has that anti-noise ability is higher, calculated amount is little, precision is than advantages of higher, and is hour more stable in displacement.At present, the DSCM field of using just gradually from the test of conventional material to some new materials tests, from macroscopic field gradually to trickle sight yardstick, from conventional environment to rugged environment relatively, progressively use, develop to dynamic accurate dynamic dispatching aspect from static quasistatic to engineering site from lab investigation.

Because the limitation that method itself has, the speckle correlation technique of single beam illumination can only be measured in-plane displacement.The scientific research personnel is just by measuring three-D displacement with DSCM with other measuring techniques combinations or by the relevant method of three-dimensional speckle.DSCM is combined with stereoscopic photograph technology or binocular measuring technique, can measure 3-D displacement field.For example the stereoscopic photography of professor Yao Xuefeng of Tsing-Hua University proposition combines with Digital Speckle Correlation Method for research 3 D deformation field; Binocular 3-dimensional digital speckle measurement of correlation 3 D deformation and 3 d shape technology that Xie Hui people professor proposes.DSCM is combined with the pin hole camera technique, and professor He Xiaoyuan of Southeast China University has proposed relevant the combining with the pinhole camera imaging model of digital picture and has measured the three-dimensional body displacement method.By the relevant method of three-dimensional speckle, the 5 little flat academicians of Chinese University of Science and Technology, professor Hu Xiaofang etc. utilize simulated experiment to obtain the interior of articles 3-D displacement field.

Utilize electronic speckle pattern interferometry (ESPI) method can measure the three-D displacement of object, have noncontact, measurement of full field, the advantage that precision is high.The electronic speckle pattern interferometry technology is based on reference light and thing light is measured in CCD target surface generation speckle interference.Therefore, three-dimensional speckle is interfered often light path more complicated.Complicated light path has increased the measuring system instability, has reduced measuring accuracy.

DSCM is combined with speckle interference, also can measure 3-D displacement field.Professor Zhang Qingchuan adopts two cover light paths, to the positive speckle measurement of correlation that adopts of test specimen, the reverse side employing speckle interference of test specimen is measured, and has realized the three-D displacement field measurement.The method is that the different surfaces of test specimen is measured, and is not the 3 D deformation on same surface.Professors Zhou Canlin etc. measure distortion to relevant combining with electronic speckle pattern interferometry of speckle, what adopt is typical speckle relevant light paths, the speckle interference image that at first the speckle interference four-step phase-shifting is gathered is processed, then the image of processing is carried out the speckle correlation computations, thereby obtain the 3 D deformation field.Used principle is then very complicated, image processing process is also very complicated, not directly to obtain required speckle pattern when utilizing speckle correlation computations in-plane displacement, but obtained through processing by the phase shifted images that gathers before and after the distortion, be difficult to obtain the numerical value of 3 D deformation field in the practical operation.

The utility model content

The purpose of this utility model is exactly in order to address the above problem, the measurement system for three-dimensional deformation that a kind of speckle is relevant and speckle interference combines is provided, it utilizes typical Michelson speckle light path to the acoplanarity displacement sensitivity, by the reference light in the control light path, realize in-plane displacement and the speckle interference measurement acoplanarity displacement of speckle measurement of correlation object, realized the three-D displacement measurement, the advantage that this system has that light path is simple, operation and data are processed simple and fast.

To achieve these goals, the utility model adopts following technical scheme:

The measurement system for three-dimensional deformation that a kind of speckle is relevant and speckle interference combines, it comprises laser instrument, the laser that laser instrument sends is sent into beam expanding lens; The beam expanding lens rear is provided with the semi-transparent semi-reflecting lens of placing with incident ray overturning angle at 45 °, and the reflected light of semi-transparent semi-reflecting lens shines measured object, and transmitted light then shines with reference to object plane, connects and composes the reference phase shift light path with reference to object plane and PZT phase-shifter; The speckle image of measured object is imaged on the ccd video camera by imaging len through semi-transparent semi-reflecting lens, utilizes two width of cloth speckle patterns of measured object distortion front and back, calculates two components of in-plane displacement; The speckle image on measured object surface is interfered speckle image with the speckle image formation with reference to object plane when reference path is worked, and is imaged on the ccd video camera by imaging len, measures object acoplanarity displacement component.

A kind of measuring method that adopts the relevant and measurement system for three-dimensional deformation that speckle interference combines of speckle, it is by the control reference path, and relevant and speckle interference combines the 3 D deformation of measuring object with digital speckle; Detailed process is: at first gather the speckle pattern before the width of cloth measured object distortion without the reference laser of reference path the time; Then the reference laser that adds reference path is realized speckle interference; Loading makes the measured object distortion, measures the measured object acoplanarity displacement in conjunction with phase-shifting technique; Remove at last the speckle pattern after reference laser gathers width of cloth measured object distortion again; Speckle pattern before and after the measured object distortion is carried out the speckle related operation, obtain two-dimensional surface intrinsic displacement component, thereby realize the 3 D deformation measurement.

Concrete steps of the present utility model are:

Step 1: the reflected light with reference to object plane consists of reference light; Without reference light the time, utilize the speckle pattern before CCD gathers the measured object distortion;

Step 2: add the reference light of reference path, realize digital speckle interference;

Step 3: load and make the measured object distortion, in conjunction with four-step phase-shifting commercial measurement measured object acoplanarity displacement w field;

Step 4: remove reference light; Utilize the speckle pattern after CCD gathers the measured object distortion;

Step 5: the speckle pattern after the speckle pattern before the measured object distortion of integrating step one and the measured object distortion of step 4, speckle pattern before and after the measured object distortion is carried out the speckle related operation, obtain two-dimensional surface intrinsic displacement component u, v field.

Acoplanarity displacement is the displacement w field perpendicular to the body surface direction in the described step 3, and concrete measuring process is:

According to phase of light wave change and deformation of body between relation:

Wherein, λ is the wavelength of used laser, and θ is the angle of illumination light and body surface normal, and w is the acoplanarity displacement of deformation of body, and u is the interior horizontal direction displacement of the face of deformation of body; Known when illumination light incident angle θ=0, have by formula (4):

Adopt existing phase-shifting technique, calculate the deformation of body phase place And then draw acoplanarity displacement w field.

The concrete steps of described step 5 are: described two-dimensional surface intrinsic displacement component is horizontal direction displacement component u and vertical direction displacement component v, and the speckle correlation computations is utilized formula (1),

$C(u,v)=\frac{\underset{i}{\overset{m}{\mathrm{\Σ}}}\underset{j}{\overset{m}{\mathrm{\Σ}}}[f(x_i,y_j)-\stackrel{\‾}{f}][g(x_i+u,y_j+v)-\stackrel{\‾}{g}]}{\sqrt{\underset{i}{\overset{m}{\mathrm{\Σ}}}\underset{j}{\overset{m}{\mathrm{\Σ}}}{[f(x_i,y_j)-\stackrel{\‾}{f}]}^2}\sqrt{\underset{i}{\overset{m}{\mathrm{\Σ}}}\underset{j}{\overset{m}{\mathrm{\Σ}}}{[g(x_i+u,y_j+v)-\stackrel{\‾}{g}]}^2}}---\left(1\right)$

Wherein, f (x, y) is the front image of distortion, (x _i, y _j) being any one displacement point in the image before the distortion, g (x ', y ') is the image after the distortion, u, v be the whole pixel displacement of corresponding point in the image of displacement point (x, y) after distortion in the corresponding original image (x ', y ') respectively, (x _i+ u, y _j+ v) be displacement point (x _i, y _j) in x _iU and y have been moved _jMoved the displacement point in the image after the distortion that v obtains,

With

Be the image subsection average gray; In order to improve measuring accuracy, find the solution in the calculating that the basis of formula (1) utilizes gradient algorithm further to carry out Displacement, the selected Calculation of correlation factor formula of gradient method be formula (1) square, i.e. formula (2);

$C(u,v)=\frac{{\left\{\underset{i}{\stackrel{m}{\mathrm{\Σ}}}\underset{j}{\stackrel{m}{\mathrm{\Σ}}}\right[f(x_i,y_j)-\stackrel{\‾}{f}\left]\right[g(x_i+u+\mathrm{\Δu},y_j+v+\mathrm{\Δv})-\stackrel{\‾}{g}\left]\right\}}^2}{\underset{i}{\overset{m}{\mathrm{\Σ}}}\underset{j}{\overset{m}{\mathrm{\Σ}}}{[f(x_i,y_j)-\stackrel{\‾}{f}]}^2\underset{i}{\overset{m}{\mathrm{\Σ}}}\underset{j}{\overset{m}{\mathrm{\Σ}}}{[g(x_i+u+\mathrm{\Δu},y_j+v+\mathrm{\Δv})-\stackrel{\‾}{g}]}^2}---\left(2\right)$

Wherein, Δ u, Δ v are the Displacement corresponding to whole pixel displacement result;

Will Taylor expansion is got first approximation, and order

Through deriving:

$\left[\begin{array}{c}\mathrm{\Δu}\\ \mathrm{\Δv}\end{array}\right]={\left[\begin{array}{cc}B& C\\ E& H\end{array}\right]}^{-1}\left[\begin{array}{c}A\\ D\end{array}\right]---\left(3\right)$

Wherein

$A=\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}\mathrm{FG}\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_x-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{FG}}_x\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{\mathrm{<figure-callout\; id="2"\; label="m\; G"\; filenames="HDA00001950135300011.png"\; state="\{\{state\}\}">m</figure-callout>}}{\mathrm{\&Sigma;}}}{G}^{}{}^2,$

$B=\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}F{G}_x\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_x-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{G_x}^2\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}\mathrm{FG},$

$C=2\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}F{G}_x\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_y-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_x\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{FG}}_y-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{G}_x{G}_y\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}\mathrm{FG},$

$D=\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}FG\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_y-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{FG}}_y\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{\mathrm{<figure-callout\; id="2"\; label="m\; G"\; filenames="HDA00001950135300011.png"\; state="\{\{state\}\}">m</figure-callout>}}{\mathrm{\&Sigma;}}}{G}^{}{}^2,$

$E=2\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}F{G}_y\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_x-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_y\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{FG}}_x-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{G}_x{G}_y\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}\mathrm{FG},$

$H=\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}F{G}_y\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_y-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{\mathrm{<figure-callout\; id="2"\; label="m\; G\; y"\; filenames="HDA00001950135300011.png"\; state="\{\{state\}\}">m</figure-callout>}}{\mathrm{\&Sigma;}}}{G}_y^{}{}_2^{}\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}\mathrm{FG},$

$G(x_i,y_j)=g(x_i+u,y_j+v)-\stackrel{\&OverBar;}{g},$

$G_x=g_x-{\stackrel{\&OverBar;}{g}}_x,$ $G_y=g_y-{\stackrel{\&OverBar;}{g}}_y,$

$F(x_i,y_j)=f(x_i,y_j)-\stackrel{\&OverBar;}{f},$

G in the formula _xG is to x in expression _iAsk local derviation, G _yG is to y in expression _jAsk local derviation, g _xExpression g (x _i+ u, y _j+ v) to x _iAsk local derviation, g _yExpression g (x _i+ u, y _j+ v) to y _jAsk local derviation,

Expression To x _iAsk local derviation,

Expression To y _jAsk local derviation, m is iterations.

The beneficial effects of the utility model: utilize typical digital speckle interference light path to the acoplanarity displacement sensitivity, by the reference light in the control light path, realize in-plane displacement and the speckle interference measurement acoplanarity displacement of speckle measurement of correlation object, realized the three-D displacement measurement.The advantage that this system has that light path is simple, operation and data are processed simple and fast.

Description of drawings

Fig. 1 is optical measuring system figure;

The speckle image of Fig. 2 when not being out of shape;

Fig. 3 for the distortion after from the face interference fringe;

Fig. 4 is the speckle image after being out of shape;

Fig. 5 is the three-D displacement horizontal direction component behind the deformation of body, the u field pattern;

Fig. 6 is the three-D displacement vertical direction component behind the deformation of body, the v field pattern;

Fig. 7 is the three-D displacement acoplanarity displacement component behind the deformation of body, the w field pattern;

Fig. 8 is process flow diagram of the present utility model.

Wherein, 1. laser instrument, 2. beam expanding lens, 3. semi-transparent semi-reflecting lens, 4. tested object plane, 5. with reference to object plane, 6.PZT phase-shifter, 7. imaging len, 8.CCD video camera.

Embodiment

The utility model is described in further detail below in conjunction with accompanying drawing and embodiment.

Among Fig. 1, the measurement system for three-dimensional deformation that a kind of speckle is relevant and speckle interference combines, it comprises the speckle relevant light paths of measuring object plane internal strain component and the speckle interference phase shift light path of measuring the acoplanarity displacement component; Behind the laser beam expanding that laser instrument 1 sends by throw light on respectively tested object plane 4 and with reference to object plane 5 of semi-transparent semi-reflecting lens 3.Semi-transparent semi-reflecting lens 3 is placed with incident light overturning angle at 45 °.The reflected light of tested object plane 4 sees through semi-transparent semi-reflecting lens 3, with reference to the reflected light of object plane 5 in semi-transparent semi-reflecting lens 3 reflections, two bundle light through imaging lens 7 post-concentrations on ccd video camera 8.

Test light path as shown in Figure 1, test specimen is the organic glass free beam, long 150.0mm, high 19.5mm, thick 18.5mm.Be coated with water paint on the free beam surface, to strengthen its reflectivity, whole experimental provision is placed on the anti-vibration platform and carries out.As light source, light beam is radiated on the free beam surface after beam expanding lens 2 expands with He-Ne laser instrument 1.By semi-transparent semi-reflecting lens 3(BS) the in addition light beam told is as reference light.During experiment, the process flow diagram of this method as shown in Figure 8, the speckle image when at first blocking reference light and gathering a width of cloth free beam and be not out of shape, as shown in Figure 2; Then add reference light, realize electronic speckle pattern interferometry; Gather object speckle interference image and subtract each other in real time, during free beam is loaded, can observe object acoplanarity displacement striped, as shown in Figure 3; Use the phase shifts such as PZT phase-shifter 6 realizations and gather speckle interference fringe pattern; At last, block reference light, again gather the speckle image after free beam is out of shape, as shown in Figure 4.

Described two-dimensional surface intrinsic displacement component is: utilize formula (1)

$C(u,v)=\frac{\underset{i}{\stackrel{m}{\mathrm{\&Sigma;}}}\underset{j}{\stackrel{m}{\mathrm{\&Sigma;}}}[f(x_i,y_j)-\stackrel{\&OverBar;}{f}][g(x_i+u,y_j+v)-\stackrel{\&OverBar;}{g}]}{\sqrt{\underset{i}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j}{\overset{m}{\mathrm{\&Sigma;}}}{[f(x_i,y_j)-\stackrel{\&OverBar;}{f}]}^2}\sqrt{\underset{i}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j}{\overset{m}{\mathrm{\&Sigma;}}}{[g(x_i+u,y_j+v)-\stackrel{\&OverBar;}{g}]}^2}}---\left(1\right)$

Wherein, f (x, y) is the front image of distortion, (x _i, y _j) being any one displacement point in the image before the distortion, g (x ', y ') is the image after the distortion, u, v be the whole pixel displacement of corresponding point in the image of displacement point (x, y) after distortion in the corresponding original image (x ', y ') respectively, (x _i+ u, y _j+ v) be displacement point (x _i, y _j) in x _iU and y have been moved _jMoved the displacement point in the image after the distortion that v obtains,

With

Be the image subsection average gray; In order to improve measuring accuracy, utilize existing gradient method further to carry out the calculating of Displacement on the basis of formula (1), the selected Calculation of correlation factor formula of gradient method be formula (1) square, i.e. formula (2)

$C(u,v)=\frac{{\left\{\underset{i}{\stackrel{m}{\mathrm{\&Sigma;}}}\underset{j}{\stackrel{m}{\mathrm{\&Sigma;}}}\right[f(x_i,y_j)-\stackrel{\&OverBar;}{f}\left]\right[g(x_i+u+\mathrm{\&Delta;u},y_j+v+\mathrm{\&Delta;v})-\stackrel{\&OverBar;}{g}\left]\right\}}^2}{\underset{i}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j}{\overset{m}{\mathrm{\&Sigma;}}}{[f(x_i,y_j)-\stackrel{\&OverBar;}{f}]}^2\underset{i}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j}{\overset{m}{\mathrm{\&Sigma;}}}{[g(x_i+u+\mathrm{\&Delta;u},y_j+v+\mathrm{\&Delta;v})-\stackrel{\&OverBar;}{g}]}^2}---\left(2\right)$

Wherein, Δ u, Δ v are the Displacement corresponding to whole pixel displacement result;

Will

Taylor expansion is got first approximation, and order

Through deriving:

$\left[\begin{array}{c}\mathrm{\&Delta;u}\\ \mathrm{\&Delta;v}\end{array}\right]={\left[\begin{array}{cc}B& C\\ E& H\end{array}\right]}^{-1}\left[\begin{array}{c}A\\ D\end{array}\right]---\left(3\right)$

Wherein

$A=\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}\mathrm{FG}\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_x-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{FG}}_x\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{<figure-callout\; id="2"\; label="G"\; filenames="HDA00001950135300011.png"\; state="\{\{state\}\}">G</figure-callout>}}^2,$

$B=\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}F{G}_x\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_x-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{G_x}^2\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}\mathrm{FG},$

$C=2\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}F{G}_x\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_y-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_x\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{FG}}_y-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{G}_x{G}_y\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}\mathrm{FG},$

$D=\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}FG\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_y-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{FG}}_y\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{<figure-callout\; id="2"\; label="G"\; filenames="HDA00001950135300011.png"\; state="\{\{state\}\}">G</figure-callout>}}^2,$

$E=2\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}F{G}_y\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_x-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_y\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{FG}}_x-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{G}_x{G}_y\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}\mathrm{FG},$

$H=\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}F{G}_y\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{GG}}_y-\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{<figure-callout\; id="2"\; label="G\; y"\; filenames="HDA00001950135300011.png"\; state="\{\{state\}\}">G</figure-callout>}}_y^{}\underset{i=1}{\overset{m}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}\mathrm{FG}.$

$G(x_i,y_j)=g(x_i+u,y_j+v)-\stackrel{\&OverBar;}{g},$

$G_x=g_x-{\stackrel{\&OverBar;}{g}}_x,G_y=g_y-{\stackrel{\&OverBar;}{g}}_y,$

$F(x_i,y_j)=f(x_i,y_j)-\stackrel{\&OverBar;}{f}.$

In the formula, G _xG is to x in expression _iAsk local derviation, G _yG is to y in expression _jAsk local derviation, g _xExpression g (x _i+ u, y _j+ v) to x _iAsk local derviation, g _yExpression g (x _i+ u, y _j+ v) to y _jAsk local derviation, Expression

To x _iAsk local derviation,

Expression

To y _jAsk local derviation, m is iterations.

Described off-surface displacement measurement process is:

Phase of light wave changes and the phase relation of deformation of body is:

Wherein, λ is the wavelength of used laser, and θ is the angle of illumination light and body surface normal, and w is the acoplanarity displacement of deformation of body, and u is the interior horizontal direction displacement of the face of deformation of body; Known that by formula (4) as illumination light incident angle θ during less than 5 °, approximate to regard change in optical path length as only relevant with acoplanarity displacement w, by formula (4):

Adopt phase-shifting technique to calculate the deformation of body phase place

And then draw the w field.

Speckle image (Fig. 2 and Fig. 4) is used for speckle correlation computations in-plane displacement u field and v field (unit: pixel) before and after the distortion.Adopt existing phase-shifting technique that speckle interference fringe pattern is processed, can obtain acoplanarity displacement w field (unit: micron).Variable shaped beam 3 D deformation component experimental result such as Fig. 5, Fig. 6, shown in Figure 7.

Experimental result shows, utilizes speckle method relevant and that speckle interference combines can measure fast and effectively the object dimensional distortion, has that light path is simple to operation, data are processed simple advantage.Experimental result v, w field and document [Sun Ping, Fan Xiangju, Wang Xinghai. based on the three-dimensional carrier frequency electronic speckle interference technique [J] of large-misplacement square glass prism. Acta Optica, 2011,31 (4): 0412012] in the result coincide better, the u field is substantially identical.

Although above-mentionedly by reference to the accompanying drawings embodiment of the present utility model is described; but be not the restriction to the utility model protection domain; one of ordinary skill in the art should be understood that; on the basis of the technical solution of the utility model, those skilled in the art do not need to pay various modifications that creative work can make or distortion still in protection domain of the present utility model.

Claims (1)

1. the measurement system for three-dimensional deformation that speckle is relevant and speckle interference combines is characterized in that it comprises laser instrument, and the laser that laser instrument sends is sent into beam expanding lens; The beam expanding lens rear is provided with the semi-transparent semi-reflecting lens of placing with incident ray overturning angle at 45 °, and the reflected light of semi-transparent semi-reflecting lens shines measured object, and transmitted light then shines with reference to object plane, connects and composes reference path with reference to object plane and PZT phase-shifter; The speckle image of measured object is imaged on the ccd video camera by imaging len through semi-transparent semi-reflecting lens, utilizes two width of cloth speckle patterns of measured object distortion front and back, calculates two components of in-plane displacement; The speckle image on measured object surface is interfered speckle image with the speckle image formation with reference to object plane when reference path is worked, and is imaged on the ccd video camera by imaging len, measures object acoplanarity displacement component.

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