CN104992414B

CN104992414B - The processing method of three-dimensional ion velocity focused image

Info

Publication number: CN104992414B
Application number: CN201510346551.8A
Authority: CN
Inventors: 唐国强; 吴向坤; 周晓国; 刘世林
Original assignee: University of Science and Technology of China USTC
Current assignee: University of Science and Technology of China USTC
Priority date: 2015-06-19
Filing date: 2015-06-19
Publication date: 2017-11-24
Anticipated expiration: 2035-06-19
Also published as: CN104992414A

Abstract

The invention provides a kind of processing method of three-dimensional ion velocity focused image.In the processing method, the optimization that image is realized by optimizing conversion to matrix converts：Singular point and negative background are deducted, carries out image translation, fitting draws rotation compensation angle, image rotating, and quantitatively implementation matrixing and symmetrization processing restore preferable three-dimensional ion velocity focused image.The VELOCITY DISTRIBUTION drawn compared with initial three-dimensional ion velocity focuses on influence using the three-dimensional ion velocity focused image that finally reduces of processing method of the present invention and angle distribution and anisotropic parameters are all more accurate.

Description

The processing method of three-dimensional ion velocity focused image

Technical field

The present invention relates to fine measuring instrument technical field, more particularly to a kind of processing of three-dimensional ion velocity focused image Method.

Background technology

At present, three-dimensional ion velocity focused image technology has become a very ripe and widely used research hand Section.The technology intuitively can accurately reflect the interior energy and angular distribution of dissociation fragment during ionic dissociation, then be excited The initial energy state population of reactant, the speed size etc. of reaction afterwards, therefore have in molecular photodissociation research, crossed molecular beam etc. Very important application.

In three-dimensional ion velocity focused image technology, for ion velocity slice image, there is special processing method. The processing method includes：Processing is optimized to ion imaging matrix；Line translation is entered to optimization matrix, obtains half drive matrix and angle Spend matrix；Calculating speed integrates and angle integration, obtains VELOCITY DISTRIBUTION and the angle distribution of ion imaging；Diagonal distribution is intended Close, obtain anisotropic parameters value during ionic dissociation.

Realize the present invention during, it is found by the applicant that the processing method of above-mentioned ion velocity slice image exist it is following Defect：During image collection, because CCD camera angle tilt or flight time mass spectrum electric field distorting etc. are difficult to what is overcome Problem, the image that can make to collect produces distortion, and existing processing method does not account for image distortion, if directly adopting Handled with the image of distortion of the existing image treatment method to collecting, the speed for the dissociation fragment that can make to obtain is differentiated It is decreased obviously and anisotropic parameters value error becomes big.

The content of the invention

(1) technical problems to be solved

In view of above-mentioned technical problem, the invention provides a kind of processing method of three-dimensional ion velocity focused image, with solution The defects of certainly prior art does not account for image distortion.

(2) technical scheme

The processing method of the three-dimensional ion velocity focused image of the present invention includes：Step A：By three-dimensional ion velocity focused image Pretreatment is optimized, optimization pretreatment includes：By the singular point in three-dimensional ion velocity focused image and negative background point button Remove；Step B：To optimizing pretreated three-dimensional ion velocity focused image, the center of image annulus is determined by drawing circle, Horizontal and vertical translation is carried out to it, the center of image annulus moved at the center of whole matrix；Step C：To image annulus The three-dimensional ion velocity focused image that moves at whole matrix center of center, calculate the distribution of its angle；Step D：To three-dimensional ion The angle distribution of velocity focusing image is fitted, and obtains CCD camera according to curve matching situation and put just do not causing image to rotate Angle, θ₀；Step E：Three-dimensional ion velocity focused image is rotated into θ₀Angle, make the symmetrical vertical of three-dimensional ion velocity focused image Axle is completely superposed with vertical curve；Step F：To rotating θ₀Three-dimensional ion velocity focused image after angle, according to its distorting event, It is compressed along transverse axis or the longitudinal axis, image is become than slightly round in the past, i.e. coarse adjustment；And step G：After completing coarse adjustment The fine setting that three-dimensional ion velocity focused image is distorted, becomes more round image.

(3) beneficial effect

The optimization that the present invention realizes image by optimizing conversion to matrix converts：Singular point and negative background are deducted, Image translation is carried out, fitting draws rotation compensation angle, image rotating, and quantitatively implements matrixing and symmetrization processing reduction Go out preferable three-dimensional ion velocity focused image, the VELOCITY DISTRIBUTION that is drawn by the three-dimensional ion velocity focused image finally reduced and Angle is distributed and anisotropic parameters is all more accurate.

Brief description of the drawings

Fig. 1 is the flow chart of the processing method of three-dimensional ion velocity focused image of the embodiment of the present invention；

Fig. 2 is the detail flowchart for optimizing pre-treatment step in processing method shown in Fig. 1；

Fig. 3 is the detail flowchart of the center translation step of image annulus in processing method shown in Fig. 1；

Fig. 4 is that the detailed process that three-dimensional ion velocity focused image angle is distributed sub-step is calculated in processing method shown in Fig. 1 Figure；

Fig. 5 is the detail flowchart that image anglec of rotation sub-step is determined in processing method shown in Fig. 1；

Fig. 6 is the detail flowchart of image spin step in processing method shown in Fig. 1；

Fig. 7 is the detail flowchart of image compression coarse steps in processing method shown in Fig. 1；

Fig. 8 is the detail flowchart of image quantitative transformation trim step in processing method shown in Fig. 1；

Fig. 9 is the detail flowchart that image VELOCITY DISTRIBUTION step is calculated in processing method shown in Fig. 1；

Figure 10 is the detail flowchart of image symmetry step in processing method shown in Fig. 1；

Figure 11 is the parent ion image schematic diagram of the embodiment of the present invention；

Figure 12 is that the parent ion image optimization of the embodiment of the present invention handles schematic diagram；

Figure 13 is that the arrange parameter of the embodiment of the present invention draws circle determination center of circle schematic diagram；

Figure 14 carries out translation schematic diagram for ion imaging after the optimization of the embodiment of the present invention；

Figure 15 is the VELOCITY DISTRIBUTION schematic diagram before the ion imaging distortion adjustment of the embodiment of the present invention；

Figure 16 is the ion imaging angle distribution schematic diagram of the embodiment of the present invention；

Figure 17 is the embodiment of the present invention by being fitted angle ion distribution determination anglec of rotation schematic diagram；

Figure 18 is the ion imaging rotation process schematic diagram of the embodiment of the present invention；

Figure 19 is that the ion imaging of the embodiment of the present invention distorts coarse adjustment schematic diagram；

Figure 20 A are the ion imaging distortion fine setting schematic diagram of the embodiment of the present invention；

Figure 20 B are the action effect schematic diagram for finely tuning each coefficient in formula of the embodiment of the present invention；

Figure 21 be the embodiment of the present invention adjustment after ion imaging VELOCITY DISTRIBUTION schematic diagram；

Figure 22 be the embodiment of the present invention adjustment after ion imaging angle fitting of distribution schematic diagram；

Figure 23 is that the ion imaging symmetrization of the embodiment of the present invention handles schematic diagram.

Embodiment

The present invention propose one kind ion imaging can be optimized, quantitative transformation, realize that image distortion is effectively adjusted Whole processing method.

Below in conjunction with specific embodiment, and referring to the drawings, the present invention will be described in further detail.Need what is illustrated It is that in accompanying drawing or specification text, the implementation that does not illustrate or describe is those of ordinary skill in art Known form, will not be described in further detail.

In one exemplary embodiment of the present invention, there is provided a kind of processing side of three-dimensional ion velocity focused image Method.Before ion imaging processing method is introduced, it should be noted that, three-dimensional ion velocity focused image can regard a matrix as, Therefore namely its corresponding matrix is operated during processing ion imaging.Fig. 1 is three-dimensional ion velocity of the embodiment of the present invention The flow chart of the processing method of focused image.As shown in figure 1, the processing method bag of the present embodiment three-dimensional ion velocity focused image Include：

Step A：Three-dimensional ion velocity focused image is optimized into pretreatment, optimization pretreatment includes：By three-dimensional from Singular point deducts with negative background point in sub- velocity focusing image；

Wherein, singular point is the great point of intensity level in matrix, and its strength values is the 10 of the maximum of ion signal point² ~10³Times, therefore need to be deducted, to be observed below to image.In addition, some negative background points are there is also in image, Negative background point refers to the point that strength values are negative, is by adopting as causing during software processing, because negative background point can be to ion speed The calculating of degree distribution and angle distribution brings certain error, therefore need to deduct it in the lump.

The purpose of this step is to eliminate the singular point and negative background point in image, understands image and shows, after it is carries out The basis of continuous operation processing, it is simply necessary.

Fig. 2 is the detail flowchart for optimizing pre-treatment step in processing method shown in Fig. 1.Fig. 2 is refer to, i, j are right respectively The row and column of matrix is answered, I (i, j) represents the matrix value of the i-th row of homography jth row.

As shown in Fig. 2 the optimization pre-treatment step specifically includes：

Step 201：I, j are assigned to initial value for 0；

Step 202：Circulation step is set, using i=i+1 as outer circulation；

Step 203：Using j=j+1 as interior circulation；

Step 204：Singular point and negative background point are deducted, that is, judge whether I (i, j) is more than M or less than 0, if so, performing Step 205；Otherwise, step 206 is performed；

Wherein, it is determined as singular point for the point more than M, the point less than 0 is determined as negative background point.

Step 205：Make I (i, j)=0；

Step 206：Judge whether j ＜ n, if so, performing step 203；Otherwise, interior circulation terminates, and performs step 207；

Step 207：Judge whether i ＜ m, if so, performing step 202；Otherwise, outer circulation terminates, the optimization of whole image Process terminates.

Wherein, the M values in step 204 can be according to the concrete condition sets itself of experiment image, as long as ensureing ion letter The purpose for deducting singular point can be reached on the premise of number point.Generally, the M values take the maximum of ion signal point 10 times are advisable (maximum of ion signal point directly can be found with max functions in a program).

Step B：To optimizing pretreated three-dimensional ion velocity focused image, the center of image annulus is determined by drawing circle Position, horizontal and vertical translation is carried out to three-dimensional ion velocity focused image, the center of image annulus is moved into whole matrix At center；

There are numerous matrix manipulation functions to directly invoke in matlab program platforms, but many handling function (such as matrixes Rotation, matrix turning etc.) all based on the center of matrix.Due in the center and whole matrix of the image annulus collected The heart is difficult to realize to be overlapped, if wanting, directly invoking correlation function is handled image annulus, is needed the center shifting of image annulus To matrix center, the step plays very important effect to simplifying later programmed.

Fig. 3 is the detail flowchart of the center translation step of image annulus in processing method shown in Fig. 1.It refer to figure 3, step B is specifically included：

The transverse translation step of image：Judge x₀With m/2 magnitude relationship (step 301), if x₀<M/2, image is increased toward i Big direction movement m/2-x₀Individual unit (step 302), if x₀>=m/2, image is moved into x toward the direction that i reduces₀- m/2 single Position (step 303).Wherein x₀,y₀The center abscissa of expression image annulus (determines) that m, n divide with ordinate by drawing circle respectively It is not the line number and columns of whole matrix, m/2, n/2 are the center of whole matrix (for given value)；

For the transverse translation of image, further detailed description is as follows：

(I) for x₀<M/2 situation, image is moved into m/2-x toward the direction that i increases₀Individual unit.The transverse translation of image Concrete operations are：

Image is divided into two pieces to be handled, wherein, j≤n, i≤m/2+x₀First piece of conduct；J≤n, m >=i>m/2+ x₀Second piece of conduct.

For first piece

(I) by i, j assigns initial value as 0；

(II) sets circulation step, and j=j+1 is as outer circulation, and i=i+1 is as interior circulation；

I (i, j) is moved to I'(i+m/2-x by (III)₀, j), i.e. I'(i+m/2-x₀, j) and=I (i, j)；

(IV) sets loop termination to walk, when i is recycled to m/2+x₀When, interior circulation terminates, outer circulation circulation primary；When j is followed Ring is recycled to m/2+x to n and i₀When, inner-outer circulation all terminates, and first piece of image translation terminates.

For second piece

I tax initial values are m/2+x by (I)₀, it is 0 that j, which assigns initial value,；

I (i, j) is moved to I'(i-m/2-x by (III)₀, j), i.e. I'(i-m/2-x₀, j) and=I (i, j)；

(IV) sets loop termination to walk, and when i is recycled to m, interior circulation terminates, outer circulation circulation primary；When j is recycled to n and i When being recycled to m, inner-outer circulation all terminates, and second piece of image translation terminates.

Now, the image transverse translation in the case of this kind is completed；

(II) for x₀>=m/2 situation, image is moved into x toward the direction that i reduces₀- m/2 units.The transverse direction of image is put down Moving concrete operations is：

Image equally is divided into two pieces to be handled, j≤n, m >=i>x₀- m/2 is as first piece；J≤n, i≤x₀- m/2 makees For second piece.

For first piece

I tax initial values are x by (I)₀- m/2, j assign initial value as 0；

I (i, j) is moved to I'(i-x by (III)₀+ m/2, j), i.e. I'(i-x₀+ m/2, j)=I (i, j)；

(IV) sets loop termination to walk, and when i is recycled to m, interior circulation terminates, outer circulation circulation primary；When j is recycled to n And i, when being recycled to m, inner-outer circulation all terminates, first piece of image translation terminates.

For second piece

(I) by i, j assigns initial value as 0；

I (i, j) is moved to I'(i+3m/2-x by (III)₀, j), i.e. I'(i+3m/2-x₀, j) and=I (i, j)；

(IV) sets loop termination to walk, when i is recycled to x₀During-m/2, interior circulation terminates, outer circulation circulation primary；When j is followed Ring is recycled to x to n and i₀During-m/2, inner-outer circulation all terminates, and second piece of image translation terminates.

Now, the image transverse translation in the case of this kind is completed；

After the completion of transverse translation, then it is completely the same to image progress longitudinal translation, the operation of its method and principle and transverse direction.

The longitudinal translation step of image：Judge y₀With n/2 magnitude relationship (step 304), if y₀<N/2, image is increased toward j Big direction movement n/2-y₀Individual unit (step 305), if y₀>=n/2, image is moved into y toward the direction that j reduces₀- n/2 single Position (step 306).

For the longitudinal translation of image, further detailed description is as follows：

(I) for y₀<N/2 situation, image is moved into n/2-y toward the direction that j increases₀Individual unit.The longitudinal translation of image Concrete operations are：

Image is divided into two pieces, i≤m, j≤n/2+y₀As first piece；I≤m, n >=j>n/2+y₀As second piece.

For first piece：

(I) by i, j assigns initial value as 0；

(II) sets circulation step, and i=i+1 is as outer circulation, and j=j+1 is as interior circulation；

I (i, j) is moved to I'(i, j+n/2-y by (III)₀), i.e. I'(i, j+n/2-y₀)=I (i, j)；

(IV) sets loop termination to walk, when j is recycled to n/2+y₀When, interior circulation terminates, outer circulation circulation primary；When i is followed Ring is recycled to n/2+y to m and j₀When, inner-outer circulation all terminates, and first piece of image translation terminates.

For second piece：

I tax initial values are that 0, j tax initial values are n/2+y by (I)₀；

I (i, j) is moved to I'(i, j-n/2-y by (III)₀), i.e. I'(i, j-n/2-y₀)=I (i, j)；

(IV) sets loop termination to walk, and when j is recycled to n, interior circulation terminates, outer circulation circulation primary；When i is recycled to m and j When being recycled to n, inner-outer circulation all terminates, and second piece of image translation terminates.

Now, the image longitudinal translation in the case of this kind is completed；

(II) for y₀>=n/2 situation, image is moved into y toward the direction that j reduces₀- n/2 units.Put down the longitudinal direction of image Moving concrete operations is：

Image is equally divided into two pieces, i≤m, n >=j>y₀- n/2 is as first piece；I≤m, j≤y₀- n/2 is as second Block.

For first piece：

J tax initial values are y by (I)₀It is 0 that-n/2, i, which assign initial value,；

I (i, j) is moved to I'(i, j-y by (III)₀+ n/2), i.e. I'(i, j-y₀+ n/2)=I (i, j)；

(IV) sets loop termination to walk, and when j is recycled to n, interior circulation terminates, outer circulation circulation primary；When i is recycled to m And j, when being recycled to n, inner-outer circulation all terminates, first piece of image translation terminates.

For second piece：

(I) by i, j assigns initial value as 0；

I (i, j) is moved to I'(i, j+3n/2-y by (III)₀), i.e. I'(i, j+3n/2-y₀)=I (i, j)；

(IV) sets loop termination to walk, when j is recycled to y₀During-n/2, interior circulation terminates, outer circulation circulation primary；When i is followed Ring is recycled to y to m and j₀During-n/2, inner-outer circulation all terminates, and second piece of image translation terminates.

Wherein, the above respectively translates when the I' matrixes introduced in step are to translate assignment and does not produce numerical value covering problem.

At the end of laterally and longitudinally translating all, the translation processing of whole image is just completed.

Step C：The three-dimensional ion velocity focused image moved to the center of image annulus at whole matrix center, calculates it Angle is distributed；

Specifically, this step includes：Between polar coordinates and rectangular co-ordinate on the basis of transformational relation, by a series of The method of weighting weight, matrix I (r, θ) in polar coordinate system is converted to by matrix I (i, j) in rectangular coordinate system；Again by certain fixed angles It is the intensity distribution at certain angle to be located at the intensity addition in required radius at degree and be multiplied by integrating factor.

Fig. 4 is the detailed stream for the angle distribution sub-step that three-dimensional ion velocity focused image is calculated in processing method shown in Fig. 1 Cheng Tu.Fig. 4 is refer to, step C is specifically included：

Step 401：With Formula of Coordinate System Transformation：X=x₀+ rcs θ, y=y₀+ rsin θ are by polar coordinates (r, θ) and rectangular co-ordinate (x, y) is connected, herein (x₀,y₀) for translation after image annulus center；

It should be carried out due to calculating angle distribution under polar coordinates (r, θ), and be rectangular co-ordinate (i, j) in previous processed step, Therefore need to establish the relation between polar coordinates and rectangular co-ordinate, calculated to carry out angle distribution.

It should be noted that, by x caused by Coordinate Conversion, y can't be with i, and j is equivalent herein, because x, y may not be whole Number, the x after only rounding, y ability and i, j are equivalent, then, after rounding, fix (x) can be assigned to i, and fix (y) can be assigned to j.Separately Outside, x-fix (x) and y-fix (y) need to use in weighting re-computation, therefore are also assigned to δ i, δ j respectively.

Step 402：By r, θ assigns initial value as 0；

Step 403：Circulation step is set, and r=r+1 is as outer circulation；

Step 404：Using θ=θ+1 as interior circulation；

Step 405：The matrix I (i, j) in rectangular co-ordinate (i, j) is changed to polar coordinates with the method for multiple spot weighting weight Matrix I (r, θ) in (r, θ), the weight of the intensity of four points it will add up and be assigned to I (r, θ) around (r, θ), wherein：

(I) I (i, j) weight is (1- δ j) * (1- δ i)；

(II) I (i, j+1) weight is δ j* (1- δ i)；

(III) I (i+1, j) weight is (1- δ j) * δ i；

(IV) I (i+1, j+1) weight is δ j* δ i；

So I (r, θ)=I (i, j) * [(1- δ j) * (1- δ i)]+I (i, j+1) * [δ j* (1- δ i)]+I (i+1, j) * [(1-δj)*δi]+I(i+1,j+1)*[δj*δi]；

Step 406：I (r, θ) is multiplied by integrating factor r²It is assigned to I'(r, θ), i.e. I'(r, θ)=I (r, θ) * r²；

Step 407：Judge whether θ<360, if so, performing step 404；Otherwise, interior circulation terminates, and performs step 408；

Step 408：Judge whether r<r_m, if so, performing step 403；Otherwise, outer circulation terminates, and performs step 409, its Middle r_mFor the total radius size of three-dimensional ion velocity focused image；

Step 409：By matrix I'(r₁:r₂,:) row added up, the intensity square in the range of 0~360 degree can be obtained Battle array, i.e. radius r₁~r₂In the range of angle distribution I'(θ)；

Step 410：By angle distribution I'(θ) normalization, i.e., find out angle distribution I' first with the max functions in matlab programs Maximum I in (θ)_mθ, then by I'(θ)/I_mθIt is assigned to I'(θ) the normalization process that angle is distributed just is completed, normalized Angle distribution I'(θ) (later referred to as angle distribution).

Step D：Normalized angle distribution to three-dimensional ion velocity focused image is fitted, according to curve matching situation Obtain CCD camera and put the angle, θ for just not causing image to rotate₀；

In the present invention, angle distribution fitting formula by：

I=(4 π)^-1*(1+βP₂(cosθ))

It is changed to：

I=(4 π)^-1*(1+βP₂(cos(θ-θ₀)))。

Using least square method during fitting, by inputting different θ₀Value, repeatedly carries out curve fitting, according to multiple Curve matching effect, finally determine θ₀Value.Therefore, angle distribution is fitted here to be not configured to obtain anisotropic parameters, but In order to determine the rotation angle θ of ion imaging according to fitting effect₀.For the θ inputted during fitting every time₀Trial value, can be according to above The angle distribution of the image of acquisition substantially determines θ₀Trial scope, that is, read angle and be distributed in close to 180 degree position maximum intensity institute Corresponding angle, θ_m, then θ₀Can be in 180- θ_mLeft and right carry out value trial.

This step includes：According to formula I=(4 π)^-1*(1+βP₂(cos(θ-θ₀))) each β value is calculated in each angle Intensity I (β, θ) at θ；Calculate certain and fix I (β, θ) of the β value at all angle, θs and angle distribution I'(θ) squared difference and； β corresponding to squared difference and minimum value (min functions can directly find out minimum value in application program) is substituted into formula I=(4 π)^-1*(1+βP₂(cos(θ-θ₀))) make the angle fitting of distribution that curve just completes image.

Wherein, β is anisotropic parameters；P₂For second order Legnedre polynomial, its implication is：

Fig. 5 is the detail flowchart for the anglec of rotation sub-step that image is determined in processing method shown in Fig. 1.Fig. 5 is refer to, should Step D is specifically included：

Sub-step D1：Input a rotation angle θ₀；

It refer to Fig. 5, in this sub-step, attempt one rotation angle θ of input₀(step 501).

Sub-step D2：One is produced between -1~2 at intervals of 0.01 β value matrix, calculates each β value in β value matrix Intensity I (β, θ) at each angle, θ；

Because the present invention is fitted using least square method, therefore need to calculate each β value strong at each angle, θ Degree (θ span is 0~360).β and θ is initialized respectively is entered as -1.01 and 0 (step 502)；Circulation is set to walk again, β =β+0.01 is used as outer circulation (step 503), and θ=θ+1 is as interior circulation (step 504)；Utilize least square fitting formula I =(4 π)^-1*(1+βP₂(cos(θ-θ₀))) intensity (step 505) of each β value at each angle, θ is calculated respectively, form The matrix of one 301 × 360, the corresponding parameter beta of row of matrix, row corresponding angle θ；(the step 506) when θ is recycled to 360, is inside followed Ring terminates, outer circulation circulation primary；(the step 507) when β is recycled to 2, outer circulation terminate, and all I (β, θ), which are calculated, to be completed. Wherein, β is the anisotropic parameters in above fitting formula, between its span is -1~2.

Sub-step D3：Calculate I (β, θ) and image of each β value at all angle, θs angle distribution I'(θ) between difference Quadratic sum, and by its assignment to C (β, k)；

It is first -1.01,0 and 0 (step 508) by β, k and θ tax initial value in this sub-step；Circulation is set to walk again, β=β+ 0.01 is used as outer circulation (step 509)；K=k+1 is as time outer circulation (step 510)；θ=θ+1 is as interior circulation (step 511)；In θ=θ+1 is circulated in this, calculate Is (β, θ) of certain β at θ angles and I'(θ) squared difference (step 512)； (the step 513) when θ is recycled to 360, interior circulation terminate, secondary outer circulation circulation primary, then certain β value angled place difference Quadratic sum is obtained and assigned and arrived in C (β, k) (initial C (β, k) is 0 matrix)；(the step when k is recycled to 10000 514), secondary outer circulation terminates, outer circulation circulation primary；Until (step 515), outer circulation terminate when β is recycled to 2, each β value Angled place squared difference and all obtained and assigned and arrived in C (β, k), wherein k is that the circulation introduced walks variable.

Sub-step D4：Minimum value in C (β, k) is found out into (the min functions in application program can directly find out minimum value), β corresponding to its minimum value is substituted into formula I=(4 π)^-1*(1+βP₂(cos(θ-θ₀))) in make curve, just complete ion shadow Fitting (the step 516) of the angle distribution of picture；

Sub-step D5：Matched curve, according to the squared difference of curve matching and to judge the θ of input₀Trial value whether Properly, when the squared difference of fitting and during less than or equal to 0.1, then the trial value inputted is confirmed as the anglec of rotation of image；If The squared difference of fitting and more than 0.1, then need to attempt other θ₀Value, above-mentioned sub-step D2~D4 is repeated, until finding fitting Squared difference and corresponding rotation compensation angle θ within 0.1₀(step 517).

Step E：Three-dimensional ion velocity focused image is rotated into θ₀Angle, make the symmetrical vertical of three-dimensional ion velocity focused image Axle is completely superposed with vertical curve；

Due to CCD camera during installation it is difficult to ensure that its base is fully horizontal, therefore the ion imaging collected The rotation of certain angle can be produced.Certain angular deviation is distributed with the angle that the rotation of image can make to calculate, and fit Anisotropic parameters is inaccurate, therefore it is necessary to carry out rotational correction to image.

Fig. 6 is the detail flowchart of image spin step in processing method shown in Fig. 1.Fig. 6 is refer to, is put down completing image Move and obtain anglec of rotation θ₀Afterwards, carry out image rotation and just seem very simple.

Concrete analysis, first input angle θ₀(step 601), recycle existing matrix rotation letter in matlab program platforms Number imrotate is directly acted on (step 602) to image, can obtain postrotational image.

Step F：To rotating θ₀Three-dimensional ion velocity focused image after angle, according to its distorting event, by it along transverse axis Or the longitudinal axis is compressed, image is set to become slightly round than before compression, i.e., to rotating θ₀Three-dimensional ion velocity focused image after angle Carry out coarse adjustment；

To image produce distortion it should be noted that, when installing CCD camera, except the base injustice mentioned in step D is asked Topic, and certain angle of inclination can be produced in horizontal or vertical direction, this ion imaging that will make to collect becomes oval. In the present invention, what the ellipse problem of processing image change was taken is the mode (being compressed the major axis of oval image) of image compression.Separately Outside, due to being only adjusted in this step with distortion of the parameter to image, therefore adjusting result can seem slightly coarse, therefore It is referred to as coarse adjustment.

Image, which becomes ellipse, two kinds：The longitudinal direction laterally wider or image than longitudinal direction of image is than laterally wider.If the horizontal stroke of image To wider, then its transverse direction should be compressed, that is, take the mode of transverse compression；If the longitudinal direction of image is wider, should be indulged To being compressed, that is, take the mode of longitudinal compression.

Because the principle and thought of longitudinal compression are just the same with transverse compression, therefore following those set forth is only with horizontal pressure Example is condensed to, longitudinal compression just repeats no more.

Fig. 7 is the embodiment flow chart of image compression coarse steps in processing method shown in Fig. 1.Fig. 7 is refer to, with transverse direction Exemplified by compression, coarse steps E includes：

Step 701：Set transverse compression modulus coeff；

Transverse compression modulus coeff span is between 0~1.Coeff values are closer to 0, image compression journey Spend smaller；For coeff values closer to 1, image compression degree is bigger.

In following steps, with mathematic(al) manipulation, θ will be rotated₀Corresponding to three-dimensional ion velocity focused image after angle Matrix conversion be a new matrix, the image corresponding to the new matrix just for compression processing after image, it is than former image slightly Circle.

Step 702：I, j are assigned to initial value for 0；

Step 703：Circulation step is set, and i=i+1 is as outer circulation；

Step 704：Using j=j+1 as interior circulation；

Step 705：Expression formula i- (i-x₀) new positions of * coeff expressions i upon compression, due to i- (i-x₀) * coeff can Can be decimal, therefore need to round it, herein using first after decimal point round up round method.First introduce and become P is measured, then by i- (i-x₀) * coeff round after value i.e. round (i- (i-x₀) * coeff) it is assigned to p；

Step 706：The matrix numerical value I (i, j) at (i, j) place is assigned to I'(p, j), wherein I' is m × n 0 matrix, is realized The compression of (i, j) in transverse direction；

Step 707：Judge whether j ＜ n, if so, performing step 704；Otherwise, interior circulation terminates, and performs step 708；

Step 708：Judge whether i ＜ m, if so, performing step 703；Otherwise, outer circulation terminates, and performs step 709；

Step 709：Circle is drawn, using circle as the contrast object of reference during image compression.Observation compression after image with it is drawn Between circle in the directive difference of institute whether all within five pixels, if so, then image and drawn circle after explanation compression It is preferable to agree with degree between shape, compression parameters input is suitable, and coarse adjustment is completed；If it is not, image and drawn circle after then explanation is compressed Between to agree with degree bad, then need to change compression parameters and repeat above compression step 702~708, until image and institute after compression Between picture is circular untill the directive difference of institute is all controlled within five pixels.

Step G：The fine setting distorted to the three-dimensional ion velocity focused image after completion coarse adjustment, makes image become more Circle；

Because the Electric Field Distribution in flight time mass spectrum will not be perfect condition, certain distortion can be produced, then, collection The three-dimensional ion velocity focused image arrived can not only produce distortion because of CCD angles, and can be because Electric Field Distribution is produced Other raw more complicated distortions.For more complicated distortion, then finer regulation is needed.

In the present invention, three-dimensional ion velocity focused image is finely adjusted, need to by a series of mathematical formulae come Realize：

I=i₁+di(s,t) (1)

Di=a₁t+a₂t²+a₃t³ (2)

J=j₁+dj(s,t) (3)

Dj=b₁s²+b₂s³+b₃ts² (4)

s(i₁(the i of)=2₁-x₀)/m (5)

t(j₁(the j of)=2₁-y₀)/n (6)

Wherein, x₀,y₀For row and column corresponding to image center in matrix, m, n are the line number and columns of whole matrix, and i, j are Certain row of matrix corresponding to former image and certain row, i₁,j₁Certain row and certain row for the matrix corresponding to image after processing, s, t are The intermediate variable of fortran.Coefficient a₁,a₂,a₃,b₁,b₂,b₃For adjustable parameter, adjusting this 6 coefficients can be to whole matrix Carry out quantitative transformation.Compared with coarse adjustment, it is adjusted in the step with distortion of six parameters to image, it adjusts process more Finely, it is more perfect to adjust result, therefore is referred to as finely tuning.

During whole conversion is realized, one of them larger difficult point is by former image homography (i, j) Calculate (i corresponding to after finely tuning₁,j₁).Because matlab computing capabilitys are limited, it is impossible to more complicated formula is implemented conversion and Derive, therefore need advanced pedestrian to derive, by fortran into polynomial form, recycle existing in matlab program platforms The function of root of a polynomial is sought, (i can be calculated₁,j₁), its specific derivation process is as follows：

(2) formula substitution (1) formula is obtained：

I=i₁+a₁t+a₂ ²+a³³ (7)

Obtained by (5) formula：

(8) formula substitution (7) formula is obtained：

(4) formula substitution (3) formula is obtained again：

J=j₁+b₁s²+b₂s³+b₃ts² (10)

Obtained by (6) formula：

(11) formula substitution (10) formula is obtained：

Now, joint (9) (12) two formula can obtain a binary cubic equation group, theoretically can directly solve change S and t value is measured, but because matlab computing capabilitys are limited, can not directly solve solution of equations.Therefore artificial conversion is needed The form of equation group, derive that a matlab can directly obtain the form of variable s and t solution.Consider through excessive kind, The roots () function for having a solution root of a polynomial in matlab programs can directly be called.So, in order to can utilize Roots () function is solved, then the equation group for needing (9) (12) two formula being combined into carries out substitution of variable, draws one Univariate polynomials.

Obtained by (9) formula：

Finally (13) formula substitution (12) formula is arranged：

More than (14) formula be one on polynomial equation that t and highest item are 9 powers, then utilize roots () letter Number just can directly obtain t solution.After t value is obtained, t values substitution (6) formula can be obtained into j₁Value.

T values are substituted into (9) formula afterwards, corresponding s values can be obtained.S values substitution (5) formula can then be obtained into corresponding i again₁ Value.

So far, whole derivation terminates, (i₁,j₁) value is computed.

Fig. 8 is the embodiment flow chart of image quantitative transformation trim step in processing method shown in Fig. 1.Fig. 8 is refer to, is had For body, step G includes：

Step 801：Input parameter a₁,a₂,a₃,b₁,b₂,b₃Setting value；

Step 802：Define one and the matrix A of I (i, j) dimension identical 0, i.e. A=I*0；

Step 803：I, j are assigned to initial value for 0；

Step 804：Circulation step is set, and i=i+1 is as outer circulation；

Step 805：Using j=j+1 as interior circulation；

Step 806：(i, j) corresponding (i after fine setting is calculated using following methods₁,j₁)：

(1) j is calculated₁Detailed process it is as follows：

First, substitution of variable is carried out to below equation group, converts thereof into the polynomial equation on t, then by the multinomial of t Formula equation solution goes out t value：

M, n are the line number and columns of whole matrix respectively, and s, t are intermediate variables, (x₀,y₀) be image circle ring center seat Mark, a₁,a₂,a₃,b₁,b₂,b₃For the adjustment parameter of input.

Then, j is calculated by following formula using t values₁：

t(j₁(the j of)=2₁-y₀)/n

(2) i is calculated₁Detailed process it is as follows：

First, s value is calculated by following formula using t values：

The s values obtained are recycled to calculate i by following formula₁：

s(i₁(the i of)=2₁-x₀)/m

Wherein, the derivation of above-mentioned calculation formula has been described in detail preceding, is no longer repeated herein.

Step 807：Due to i₁,j₁May not be integer, therefore need to be to i₁,j₁Rounded, and the value after rounding is assigned to respectively I', j', the mode rounded downwards is taken in this step.

Step 808：I can be used when carrying out weighting re-computation₁,j₁Respectively with i', j' difference, therefore difference need to be distinguished It is assigned to δ i', δ j'；

Step 809：Matrix corresponding to image is implemented conversion by the method for reusing weighting weight.

In order that the image each point after fine setting conversion is more coherent, the mode for reusing weighting weight herein is operated, I.e.

(I) A (i', j')=A (i', j')+I (i, j) * (1- δ i') * (1- δ j')；

(II) A (i', j'+1)=A (i', j'+1)+I (i, j) * (1- δ i') * δ j'；

(III) A (i'+1, j')=A (i'+1, j')+I (i, j) * δ i'* (1- δ j')；

(IV) A (i'+1, j'+1)=A (i'+1, j'+1)+I (i, j) * δ i'* δ j'.

Step 810：Judge whether j ＜ n, if so, performing step 805；Otherwise, interior circulation terminates, and performs step 811；

Step 811：Judge whether i ＜ m, if so, performing step 804；Otherwise, outer circulation terminates, then caused matrix is just It is the matrix corresponding to the image after finely tuning.

Step H：To the three-dimensional ion velocity focused image after fine setting, its VELOCITY DISTRIBUTION is calculated, according to the VELOCITY DISTRIBUTION Resolution ratio determines whether to continue to finely tune, if it is, a of input need to be adjusted₁,a₂,a₃,b₁,b₂,b₃Setting value, weight It is new to perform step G；Otherwise, step I is performed；

Abovementioned steps C is the angle distribution for calculating three-dimensional ion velocity focused image, and calculating angle distribution is：By matrix I (r, θ) It is located at the intensity addition in required radius at certain fixed angle and is multiplied by integrating factor.So for the meter of VELOCITY DISTRIBUTION Calculation is by the intensity addition being located at matrix I (r, θ) certain radii fixus in required angular range and is multiplied by integrating factor Draw the intensity distribution at certain radii fixus.

Fig. 9 is the detail flowchart that image VELOCITY DISTRIBUTION step is calculated in processing method shown in Fig. 1.Fig. 9 is refer to, specifically Analysis, step intermediate portion reason method and process and step C are the same.

As illustrated, its step 901,902,903,904,905,907,908 with shown in Fig. 4, only step 906, 909,910,911 is otherwise varied.Because calculating speed distribution and angle are distributed, there is the difference of integrating factor, therefore angle, θ_min ~θ_maxIn the range of VELOCITY DISTRIBUTION be calculated as follows：By matrix I (:,θ_min:θ_max) in all matrix elements be multiplied by integrating factor r²| Sin θ | (step 906), then matrix column is added up, just obtain angle, θ_min~θ_maxIn the range of VELOCITY DISTRIBUTION I " (r) (step It is rapid 909).

Specifically, step H is specifically included：

Step 901：With Formula of Coordinate System Transformation：X=x₀+ rcos θ, y=y₀+ rsin θ are by polar coordinates r, θ and rectangular co-ordinate X, y are connected；

Step 902；By r, it is 0 that θ, which assigns initial value,；

Step 903：Circulation step is set, and r=r+1 is as outer circulation；

Step 904：Using θ=θ+1 as interior circulation；

Step 905：The matrix I (i, j) in rectangular co-ordinate (i, j) is changed to polar coordinates with the method for multiple spot weighting weight Matrix I (r, θ) in (r, θ), the weight of the intensity of four points it will add up and be assigned to I (r, θ) around (r, θ), wherein：

(I) I (i, j) weight is (1- δ j) * (1- δ i)；

(II) I (i, j+1) weight is δ j* (1- δ i)；

(III) I (i+1, j) weight is (1- δ j) * δ i；

(IV) I (i+1, j+1) weight is δ j* δ i；

So I (r, θ)=I (i, j) * [(1- δ j) * (1- δ i)]+I (i, j+1) * [δ j* (1- δ i)]+I (i+1, j) * [(1-δj)*δi]+I(i+1,j+1)*[δj*δi]

Step 906：Make I " (r, θ)=I (r, θ) * r²|sinθ|；

Step 907：Judge whether θ<360, if it is, performing step 904；Otherwise, interior circulation terminates, and performs step 908；

Step 908：Judge whether r<r_m, if it is, performing step 903；Otherwise, outer circulation terminates, and performs step 909, Wherein r_mFor the total radius size of three-dimensional ion velocity focused image；

Step 909：By matrix I " (r, θ) in θ_min<θ<θ_maxIn the range of row added up, obtain three-dimensional ion velocity and gather Its VELOCITY DISTRIBUTION I " (r) of burnt image, wherein θ_min,θ_maxThe lower and upper limit of respectively required angular range；

Step 910：VELOCITY DISTRIBUTION I " (r) is normalized, i.e., finds out speed point first with the max functions in matlab programs Maximum I in cloth I " (r)_mr, then by I " (r)/I_mrThe normalization process that I " (r) just completes VELOCITY DISTRIBUTION is assigned to, is obtained Normalized VELOCITY DISTRIBUTION I " (r) (later referred to as VELOCITY DISTRIBUTION)；

Step 911：Judge whether the resolution ratio of normalized VELOCITY DISTRIBUTION has reached and obtain three-dimensional ion velocity focusing The resolution ratio of the instrument of image, if it is, performing step I, otherwise, adjust parameter a in trim step₁,a₂,a₃,b₁,b₂,b₃'s Setting value, re-execute step G.

For step H it should be noted that the resolution ratio of VELOCITY DISTRIBUTION can be to a in fine setting step₁,a₂,a₃,b₁,b₂,b₃Parameter The appropriate level of regulation makes careful feedback, if the resolution ratio of VELOCITY DISTRIBUTION focuses on shadow closer to the three-dimensional ion velocity is obtained The resolution ratio of the instrument of picture, then illustrate that parameter regulation must be more suitable；If the resolution ratio of VELOCITY DISTRIBUTION more deviate obtain the three-dimensional from The resolution ratio of the instrument of sub- velocity focusing image, then illustrate that parameter regulation must be more improper.Three-dimensional ion velocity after fine setting When the resolution ratio of instrument of the resolution ratio of the VELOCITY DISTRIBUTION of focused image with obtaining the three-dimensional ion velocity focused image is identical, ginseng Number is provided with, and fine setting terminates.

It can be seen from the above description that step G is to connect each other with step H, it is closely related.On the one hand, lead in step G The resolution ratio of the VELOCITY DISTRIBUTION calculated in step H can be changed by overregulating parameter；On the other hand, the speed calculated in step H The resolution ratio of degree distribution can feed back the whether suitable of parameter regulation in step G.

Step I：Symmetrization processing is carried out to the three-dimensional ion velocity focused image after the completion of fine setting, after obtaining processing Image, image signal to noise ratio compared with former image is higher.

By the symmetrization processing of three-dimensional ion velocity focused image its signal to noise ratio can be made to become higher.In the step The symmetrization processing of image includes following symmetrization and handles at least one：Symmetrical above and belowization, symmetricalization, a quarter Symmetrization, the processing of these three symmetrizations can be selected as needed.

Figure 10 is the detail flowchart of image symmetry step in processing method shown in Fig. 1.Reference picture 10, concrete analysis is such as Under：

Due to having been completed that image translates in stepb, symmetrization operation is now carried out, process will become very simple It is single, matrix can be directly invoked in the step and spins upside down function flipud () and left and right upset function fliplr () to image Corresponding matrix is operated.Specifically, step I includes：

Step 1001：By matrix I and matrix flipud (I) after spinning upside down it is cumulative after divided by 2, obtain symmetrical above and below flat New matrix after, the signal to noise ratio of the image corresponding to this matrix will double；

Step 1002：By the matrix I and matrix fliplr (I) after the upset of left and right it is cumulative after divided by 2, obtain symmetrical flat New matrix after, the signal to noise ratio of the image of gained will be higher.

The present embodiment can be realized in matlab program platforms using GUI.Below with reference to specific example and The GUI of matlab programs carries out further description to the video data processing method of the present embodiment.

With oxygen photodissociation O₂+4hv(224.998nm)→O⁺+O+e^-Exemplified by, gather O⁺Three-dimensional ion velocity focus on shadow Picture.

(1) click on " File " → " Open ... " → being loaded into initial data → and make raw video.As shown in figure 11, it is this hair The parent ion image schematic diagram of bright embodiment, the raw video shown in figure is very dark, is due to that singular point is deposited in image So that signaling point contrast is too low caused.Therefore need followed by image optimization.

(2) " image optimization " button is clicked on, singular point therein is deducted with negative background point, as shown in figure 12, after optimization Image clearly show that.

(3) arrange parameter draw circle, as shown in figure 13, central coordinate of circle, the radius of circle, circle thickness parameters all can be as needed Sets itself.Circle is drawn by changing parameter in Figure 13, the image center coordinate finally determined is (692,495).

(4) click on " image translation " button, by image center from (692,495) move to whole matrix center (688, 520).As shown in figure 14, it can determine that image center has moved into (688,520) by drawing circle again.

(5) its VELOCITY DISTRIBUTION can be now calculated the image after translation to be distributed with angle.

Click on " VELOCITY DISTRIBUTION " button, it may appear that entitled sdfb subwindow, as shown in figure 15, in sdfb windows Can the voluntarily scope of input angle integration as needed, the limit of integration selected in figure is 0~360 °, and its VELOCITY DISTRIBUTION result is such as Shown in Figure 15.Can be seen that from the velocity contour in figure, a peak only shown in 460 pixels or so, but Figure 12, 13rd, it can find out that the outermost of image does not only have an annulus to exist in 14.By drawing circle it will be clearly understood that the speed to image is divided The poor resolution ratio of cloth curve is caused by image distortion.

Click on " distribution of fitting angle " button, it may appear that entitled beta_fit subwindow, as shown in figure 16, in window In can the voluntarily scope of input radius as needed, the radius of Figure 16 selections is 208~224 (annulus integrated can be from The circular understanding drawn in Figure 14), its angle distribution results is as shown in figure 16.Afterwards, one rotation compensation angle viewing angle of input is attempted Fitting of distribution situation, final in Figure 17 to determine when rotation compensation angle is 1.0 ° by repeatedly attempting, the difference of angle fitting of distribution Quadratic sum was 0.0600748 (being less than 0.1), therefore the image anglec of rotation can be determined 1.0 °, in addition, the β value exported in the window is clear Chu is shown as 1.51 (operation all can directly read β value every time).

(6) " image rotation " button is clicked on, the subwindow for an entitled txxz occur, as shown in figure 18.Will be true in Figure 17 1.0 ° fixed of the anglec of rotation is directly inputted, then clicks on " image rotating " button, and image after rotation will be shown in Main windows.

(7) distortion adjustment can be carried out after image rotation, clicks on " adjustment distortion " button, one entitled tznq's of appearance Subwindow, as shown in figure 19.

Drawn by above drawing round observation, the image of collection need to carry out transverse compression coarse adjustment laterally wider.Input is horizontal To the compressed coefficient, " transverse direction " operation button is clicked on, image after coarse adjustment can be shown in Main windows.By compare compression after shadow Picture and drawn circular difference, it is final to determine that obtained image effect is best when transverse compression modulus is 0.015.In addition, need If, should be in input coefficient in square frame corresponding to longitudinal compression coefficient it should be noted that want to carry out image longitudinal compression, then click on " longitudinal direction " button brings into operation.

After the completion of coarse adjustment, start to finely tune.As shown in FIG. 20 A, fine setting area is provided with 6 adjustable parameter a₁,a₂,a₃,b₁,b₂,b₃, Treat that this 6 parameters all after the completion of setting, click on " adjustment " button, into the operation phase, a prompting occurs in interface The progress bar of " Please wait ... ", after progress bar runs and expires and close, whole trim process is completed.And then justified using picture Instrument, by the image after processing compared with the circle drawn.By changing adjustable parameter repeatedly, the image after processing must can be made Effect reaches best.It is final to determine to work as a by multiple parameter regulation shown in Figure 20 A₁,a₂,a₃,b₁,b₂,b₃Respectively 5, -7, - When 1,2.5,1,1, image effect is optimal after processing.Finally, below will be to a for the needs of regulation₁,a₂,a₃,b₁,b₂,b₃Respectively Action effect during individual parameter regulation is mapped explanation respectively：

Figure 20 B are the action effect schematic diagram for finely tuning each coefficient in formula of the embodiment of the present invention.It refer to Figure 20 B Understand the implication of parameters, here is omitted.

Following circular dynamic trend, all it is corresponding a certain parameter independent role (other specification is all 0), and the parameter is set Occur in the case of for positive number.Therefore when all parameters are all non-zero, caused total effect is each parameter regulation effect Plus and.

(8) VELOCITY DISTRIBUTION of image after adjusting is calculated, as shown in figure 21." VELOCITY DISTRIBUTION " clicked in Main interfaces is pressed Button, there are sdfb windows, the angle limit of integration of input is 0~360 ° as step 5.In order to show the present invention to image Treatment effect, by being compared in the velocity distribution curve and Figure 15 in Figure 21, hence it is evident that find out the VELOCITY DISTRIBUTION in Figure 21 There are 3 peaks in 460 pixels or so in curve, and there was only 1 big envelope in Figure 15.In addition, in 440~450 pixel point ranges, Each peak in Figure 21 is it is clear that and can only also see several envelope peaks in Figure 15.Therefore, velocity distribution curve is compared Compared with, just can direct feel to velocity distribution curve resolution ratio image adjustment after be improved significantly.In addition, for now counting The velocity distribution curve calculated, it can also effectively be judged to finely tune parameter a in (7) according to its resolution ratio₁,a₂,a₃,b₁,b₂,b₃Set It is whether suitable.

Angle distribution and the anisotropic parameters of image after adjusting are calculated, as shown in figure 22.Click on " the fitting in Main interfaces Angle is distributed " button, there are beta_fit windows, the radius 208~224 inputted as step 5, operation " angle distribution " is pressed Button, draw angular distribution.Carry out anisotropic parameters fitting afterwards, rotation compensation angle now and difference in step 5, by In having carried out image rotation processing before this, so when rotation compensation angle should be 0.The anisotropy that will be obtained in Figure 22 Parameter beta=1.56 are compared with β=1.51 in Figure 17, anisotropic parameters twice difference.Introduced in step E Image is mentioned when rotating, due to image rotation and distortion the problems such as, the anisotropic parameters value that fits can be made inaccurate.That , after the rotation and distortion of image are processed, the anisotropic parameters value at this moment obtained must be more accurate, therefore β=1.56 It is more credible.

(9) in order to improve the signal to noise ratio of image, image symmetry processing can be also carried out, as shown in figure 23.Click on Main circle " image symmetry " button in face, there is entitled txdc subwindow.Three buttons in txdc windows can be as needed Voluntarily select, be " symmetrical above and below ", " symmetrical ", " a quarter is symmetrical " respectively.Figure 23 shows by a quarter Image after symmetrization processing, compared with the image before symmetrization, signal to noise ratio significantly improves a lot.

The present embodiment implements operation by the GUI (visualization interface) in matlab program platforms, and interface is simple, operable Property is strong, can directly observe output result, very intuitively.In addition, program all pays attention to preserving to the image matrix after processing, so as to Family carries out other follow-up processing.Image output can also be saved as picture format, convenient backup by user as needed.Moreover, journey A Help menu is also added in sequence, the implication of some formula in the process for using and interface of program is described in menu, newly User can be by checking that Help menus skillfully use in a short time.By the present invention, user can be quickly by three-dimensional ion velocity Focused image is accurately and efficiently handled, and is directly obtained the related physical quantity during ionic dissociation, is substantially increased work Efficiency.

It should be noted that the whole image treatment method of the present invention can not only be realized in matlab program platforms, also It can be realized by other programming languages.The thinking and approach application that the person skilled of this area can be introduced according to the present invention A variety of programming languages reach the optimum efficiency of image processing.

So far, all the elements of the three-dimensional ion velocity focused image processing method of the present invention, which are all introduced, finishes.This implementation Example to image by optimizing and quantitative transformation, so as to get ionic dissociation during each physical quantity it is more accurate.

In addition, the above-mentioned definition to each element and method is not limited in various concrete structures, the shape mentioned in embodiment Shape or mode.Such as：

(1) demonstration of the parameter comprising particular value can be provided herein, but these parameters are worth accordingly without being definitely equal to, and It is that can be similar to analog value in acceptable error margin or design constraint；

(2) direction term mentioned in embodiment, such as " on ", " under ", "front", "rear", "left", "right" etc., only it is ginseng The direction of accompanying drawing is examined, is not used for limiting the scope of the invention；

(3) unless specifically described or the step of must sequentially occur, the order of above-mentioned steps have no be limited to it is listed above, And it can change or rearrange according to required design.

(4) consideration that above-described embodiment can be based on design and reliability, the collocation that is mixed with each other uses or and other embodiment Mix and match uses, i.e., the technical characteristic in different embodiments can freely form more embodiments.

(5) provided herein algorithm and display not with the intrinsic phase of any certain computer, virtual system or miscellaneous equipment Close.Various general-purpose systems can also be used together with teaching based on this.As described above, this kind of system is constructed to want The structure asked is obvious.In addition, the present invention is not also directed to any certain programmed language.It should be understood that it can utilize each Kind programming language realizes the content of invention described herein, and the description done above to language-specific is to disclose this The preferred forms of invention.

In summary, the present invention three-dimensional ion velocity focused image can be optimized, quantitative transformation, realize image distortion Effective adjustment, the ion velocity that finally obtains is differentiated higher and anisotropic parameters more accurate.

Particular embodiments described above, the purpose of the present invention, technical scheme and beneficial effect are carried out further in detail Describe in detail it is bright, should be understood that the foregoing is only the present invention specific embodiment, be not intended to limit the invention, it is all Within the spirit and principles in the present invention, any modification, equivalent substitution and improvements done etc., it should be included in the guarantor of the present invention Within the scope of shield.

Claims

A kind of 1. processing method of three-dimensional ion velocity focused image, it is characterised in that including：

Step A：Three-dimensional ion velocity focused image is optimized into pretreatment；

Step B：To optimizing pretreated three-dimensional ion velocity focused image, the centre bit of image annulus is determined by drawing circle Put, horizontal and vertical translation is carried out to it, the center of image annulus moved at the center of whole matrix；

Step C：The three-dimensional ion velocity focused image moved to the center of image annulus at whole matrix center, calculate its angle point Cloth；

Step D：Angle distribution to three-dimensional ion velocity focused image is fitted, and CCD camera is obtained according to curve matching situation Put the angle, θ for just not causing image to rotate₀；

Step E：Three-dimensional ion velocity focused image is rotated into θ₀Angle, make the symmetry longitudinal axis of three-dimensional ion velocity focused image with Vertical curve is completely superposed；

Step F：To rotating θ₀Three-dimensional ion velocity focused image after angle, according to its distorting event, by it along transverse axis or the longitudinal axis It is compressed, image is become than slightly round in the past, i.e. coarse adjustment；And

Step G：The fine setting distorted to the three-dimensional ion velocity focused image after coarse adjustment, becomes more round image.
2. processing method according to claim 1, it is characterised in that the optimization pretreatment in the step A includes：By three The singular point tieed up in ion velocity focused image deducts with negative background point；

Wherein, the singular point refers to：Strength values are the 10 of the maximum of ion signal point²~10³Point again；Negative background point Refer to：Strength values are the points of negative.
3. processing method according to claim 1, it is characterised in that the step B includes：

Sub-step B1：The centre coordinate that image annulus is determined by drawing circle is (x₀,y₀), the center position coordinates of whole matrix are (m/2, n/2), wherein, m, n are the line number and columns of whole matrix respectively；

Sub-step B2：Transverse translation is carried out to three-dimensional ion velocity focused image：(I) for x₀<M/2 situation, by image toward i The direction movement m/2-x of increase₀Individual unit；(II) for x₀>=m/2 situation, image is moved into x toward the direction that i reduces₀-m/2 Individual unit；And

Sub-step B3：Longitudinal translation is carried out to three-dimensional ion velocity focused image：(I) for y₀<N/2 situation, by image toward j The direction movement n/2-y of increase₀Individual unit；(II) for y₀>=n/2 situation, image is moved into y toward the direction that j reduces₀-n/2 Individual unit.
4. processing method according to claim 1, it is characterised in that the step C includes：

Sub-step C1：With Formula of Coordinate System Transformation：X=x₀+ rcos θ, y=y₀+ rsin θ are by polar coordinates r, θ and rectangular co-ordinate x, y Connect, herein (x₀,y₀) for translation after image annulus center, in addition, fix (x) is assigned into i, fix (y) is assigned to J, x-fix (x) and y-fix (y) are assigned to δ i, δ j respectively；And

Sub-step C2：The angle point of three-dimensional ion velocity focused image is obtained by the three-dimensional ion velocity focused image under polar coordinates Cloth.
5. processing method according to claim 4, it is characterised in that in the sub-step C2, following steps are performed, by pole Three-dimensional ion velocity focused image under coordinate obtains the angle distribution of three-dimensional ion velocity focused image：

Step 402：By r, θ assigns initial value as 0；

Step 403：Circulation step is set, using r=r+1 as outer circulation；

Step 404：Using θ=θ+1 as interior circulation；

Step 405：With multiple spot weighting weight method by rectangular co-ordinate (i, j) matrix I (i, j) conversion to polar coordinates (r, Matrix I (r, θ) in θ), the weight of the intensity of four points it will add up and be assigned to I (r, θ) around (r, θ)；

Step 406：I (r, θ) is multiplied by integrating factor r²It is assigned to I'(r, θ)；

Step 407：Judge whether θ<360, if it is, performing step 404；Otherwise, interior circulation terminates, and performs step 408；

Step 408：Judge whether r<r_m, if it is, performing step 403；Otherwise, outer circulation terminates, and performs step 409, wherein r_m For the total radius size of three-dimensional ion velocity focused image；

Step 409：By matrix I'(r₁:r₂,:) row added up, obtain the intensity matrix in the range of 0~360 degree, i.e. radius r₁~r₂In the range of angle distribution I'(θ)；

Step 410：By angle distribution I'(θ) normalization.
6. processing method according to claim 5, it is characterised in that in the step 405：

(I) I (i, j) weight is (1- δ j) * (1- δ i)；

(II) I (i, j+1) weight is δ j* (1- δ i)；

(III) I (i+1, j) weight is (1- δ j) * δ i；

(IV) I (i+1, j+1) weight is δ j* δ i；

So I (r, θ)=I (i, j) * [(1- δ j) * (1- δ i)]+I (i, j+1) * [δ j* (1- δ i)]+I (i+1, j) * [(1- δ j)*δi]+I(i+1,j+1)*[δj*δi]。
7. processing method according to claim 5, it is characterised in that the step D includes：

Sub-step D1：Input a rotation angle θ₀；

Sub-step D2：One is produced between -1~2 at intervals of 0.01 β value matrix, calculates in β value matrix each β value every Intensity I (β, θ) at individual angle, θ, wherein β are the anisotropic parameters of three-dimensional ion velocity focused image；

Sub-step D3：Calculate the angle distribution I'(θ of I (β, θ) corresponding to each β value and image) between squared difference and, and general For its assignment to C (β, k), wherein k is that the circulation introduced walks variable；

Sub-step D4：Minimum value in C (β, k) is found out, the β corresponding to its minimum value is substituted into least square fitting formula I=(4 π)^-1*(1+βP₂(cos(θ-θ₀))) in make curve, complete ion imaging angle distribution fitting, wherein, P₂Strangled for second order Allow moral multinomial；

Sub-step D5：Matched curve, according to the squared difference of curve matching and to judge the θ of input₀Trial value it is whether suitable, When the squared difference of fitting and during less than or equal to 0.1, then the trial value inputted is confirmed as the anglec of rotation of image；If fitting Squared difference and more than 0.1, it tries other θ₀Value, repeat above-mentioned sub-step D2~D5.
8. processing method according to claim 7, it is characterised in that between the span of the parameter beta is -1~2, The sub-step D2 includes：

Step 501：Attempt one rotation angle θ of input₀；

Step 502：β and θ is initialized respectively is entered as -1.01 and 0；

Step 503：Circulation step is set, using β=β+0.01 as outer circulation；

Step 504：Using θ=θ+1 as interior circulation；

Step 505：Utilize least square fitting formula I=(4 π)^-1*(1+βP₂(cos(θ-θ₀))) each β value is calculated every Intensity at individual angle, θ；

Step 506：Judge whether θ<360, if it is, performing step 504；Otherwise, interior circulation terminates, and performs step 507；

Step 507：Judge whether β<2, if it is, performing step 503；Otherwise, outer circulation terminates, and performs sub-step D3.
9. processing method according to claim 7, it is characterised in that in the step F, according to following steps to three-dimensional from Sub- velocity focusing image carries out transverse axis compression：

Step 701：Set compressed coefficient coeff；

Step 702：I, j are assigned to initial value for 0；

Step 703：Circulation step is set, using i=i+1 as outer circulation；

Step 704：Using j=j+1 as interior circulation；

Step 705：Variable p is introduced, by round (i- (i-x₀) * coeff) it is assigned to p；

Step 706：The matrix numerical value I (i, j) at (i, j) place is assigned to I'(p, j), wherein I' is m × n 0 matrix, realize (i, J) in the compression of transverse direction；

Step 707：Judge whether j ＜ n, if so, performing step 704；Otherwise, interior circulation terminates, and performs step 708；

Step 708：Judge whether i ＜ m, if so, performing step 703；Otherwise, outer circulation terminates, and performs step 709；

Step 709：Circle is drawn, using circle as the contrast object of reference during image compression, judges image and drawn circle after compression Between in the directive difference of institute whether all within five pixels, if so, then transverse compression coarse adjustment is completed, perform step G； Otherwise, change compression parameters coeff and repeat above compression step 702~708.
10. processing method according to claim 9, it is characterised in that the step G according to following step to coarse adjustment after The fine setting that is distorted of three-dimensional ion velocity focused image：

Step 801：Input parameter a₁,a₂,a₃,b₁,b₂,b₃Setting value；

Step 802：Define one and the matrix A of I (i, j) dimension identical 0, i.e. A=I*0；

Step 803：I, j are assigned to initial value for 0；

Step 804：Circulation step is set, and i=i+1 is as outer circulation；

Step 805：Using j=j+1 as interior circulation；

Step 806：Calculate (i, j) (i corresponding to after fine setting₁,j₁)；

Step 807：To i₁,j₁Rounded, the value after rounding is assigned to i', j' respectively；

Step 808：Calculate i₁,j₁Respectively with i', j' difference, difference is assigned to δ i', δ j' respectively；

Step 809：Matrix corresponding to image is implemented conversion by the method using weighting weight；

Step 810：Judge whether j ＜ n, if so, performing step 805；Otherwise, interior circulation terminates, and performs step 811；

Step 811：Judge whether i ＜ m, if so, performing step 804；Otherwise, outer circulation terminates, then caused matrix is micro- The matrix corresponding to image after tune.
11. processing method according to claim 10, it is characterised in that in the step 806, calculate with the following method Go out (i, j) (i corresponding to after fine setting₁,j₁)：

(1) j is calculated₁：

First, substitution of variable is carried out to below equation group, converts thereof into the polynomial equation on t, then the multinomial side by t Journey solves t value：

<mfenced open = "{" close = ""> <mtable> <mtr> <mtd> <mrow> <mi>j</mi> <mo>=</mo> <mrow> <mo>(</mo> <mfrac> <mi>n</mi> <mn>2</mn> </mfrac> <mo>)</mo> </mrow> <mi>t</mi> <mo>+</mo> <msub> <mi>y</mi> <mn>0</mn> </msub> <mo>+</mo> <msub> <mi>b</mi> <mn>1</mn> </msub> <msup> <mi>s</mi> <mn>2</mn> </msup> <mo>+</mo> <msub> <mi>b</mi> <mn>2</mn> </msub> <msup> <mi>s</mi> <mn>3</mn> </msup> <mo>+</mo> <msub> <mi>b</mi> <mn>3</mn> </msub> <msup> <mi>ts</mi> <mn>2</mn> </msup> </mrow> </mtd> </mtr> <mtr> <mtd> <mrow> <mi>s</mi> <mo>=</mo> <mfrac> <mn>2</mn> <mi>m</mi> </mfrac> <mrow> <mo>(</mo> <mi>i</mi> <mo>-</mo> <msub> <mi>x</mi> <mn>0</mn> </msub> <mo>-</mo> <msub> <mi>a</mi> <mn>1</mn> </msub> <mi>t</mi> <mo>-</mo> <msub> <mi>a</mi> <mn>2</mn> </msub> <msup> <mi>t</mi> <mn>2</mn> </msup> <mo>-</mo> <msub> <mi>a</mi> <mn>3</mn> </msub> <msup> <mi>t</mi> <mn>3</mn> </msup> <mo>)</mo> </mrow> </mrow> </mtd> </mtr> </mtable> </mfenced>

M, n are the line number and columns of whole matrix respectively, and s, t are intermediate variables, (x₀,y₀) for translation after image circle ring center Coordinate, a₁,a₂,a₃,b₁,b₂,b₃For the adjustment parameter of input；

Then, j is calculated by following formula using t values₁：

t(j₁(the j of)=2₁-y₀)/n

(2) i is calculated₁：

First, s value is calculated by following formula using t values：

<mrow> <mi>i</mi> <mo>=</mo> <mrow> <mo>(</mo> <mfrac> <mi>m</mi> <mn>2</mn> </mfrac> <mo>)</mo> </mrow> <mi>s</mi> <mo>+</mo> <msub> <mi>x</mi> <mn>0</mn> </msub> <mo>+</mo> <msub> <mi>a</mi> <mn>1</mn> </msub> <mi>t</mi> <mo>+</mo> <msub> <mi>a</mi> <mn>2</mn> </msub> <msup> <mi>t</mi> <mn>2</mn> </msup> <mo>+</mo> <msub> <mi>a</mi> <mn>3</mn> </msub> <msup> <mi>t</mi> <mn>3</mn> </msup> </mrow>

The s values obtained are recycled to calculate i by following formula₁：

s(i₁(the i of)=2₁-x₀)/m。
12. processing method according to claim 10, it is characterised in that in the step 809, according to the following formula using weighting Matrix corresponding to image is implemented conversion by the method for weight：

(I) A (i', j')=A (i', j')+I (i, j) * (1- δ i') * (1- δ j')；

(II) A (i', j'+1)=A (i', j'+1)+I (i, j) * (1- δ i') * δ j'；

(III) A (i'+1, j')=A (i'+1, j')+I (i, j) * δ i'* (1- δ j')；

(IV) A (i'+1, j'+1)=A (i'+1, j'+1)+I (i, j) * δ i'* δ j'.
13. processing method according to claim 10, it is characterised in that also include after the G：

Step H：To the three-dimensional ion velocity focused image after fine setting, its VELOCITY DISTRIBUTION is calculated, the resolution according to the VELOCITY DISTRIBUTION Rate determines whether to continue to finely tune, if it is, input parameter a need to be adjusted₁,a₂,a₃,b₁,b₂,b₃Setting value, again Perform step G.
14. processing method according to claim 13, it is characterised in that the step H includes：

Step 901：With Formula of Coordinate System Transformation：X=x₀+ rcos θ, y=y₀+ rsin θ join polar coordinates r, θ and rectangular co-ordinate x, y System gets up；

Step 902：By r, it is 0 that θ, which assigns initial value,；

Step 903：Circulation step is set, and r=r+1 is as outer circulation；

Step 904：Using θ=θ+1 as interior circulation；

Step 905：With multiple spot weighting weight method by rectangular co-ordinate (i, j) matrix I (i, j) conversion to polar coordinates (r, Matrix I (r, θ) in θ)；

Step 906：Make I " (r, θ)=I (r, θ) * r²|sinθ|；

Step 907：Judge whether θ<360, if it is, performing step 904；Otherwise, interior circulation terminates, and performs step 908；

Step 908：Judge whether r<r_m, if it is, performing step 903；Otherwise, outer circulation terminates, and performs step 909, wherein r_m For the total radius size of three-dimensional ion velocity focused image；

Step 909：By matrix I " (r, θ) in θ_min<θ<θ_maxIn the range of row added up, obtain three-dimensional ion velocity and focus on shadow The VELOCITY DISTRIBUTION I " (r) of picture, wherein θ_min,θ_maxThe lower and upper limit of respectively required angular range；

Step 910：VELOCITY DISTRIBUTION I " (r) is normalized；

Step 911：Judge whether the resolution ratio of normalized VELOCITY DISTRIBUTION has reached and obtain the three-dimensional ion velocity focused image Instrument resolution ratio, if NO, then adjust trim step in parameter a₁,a₂,a₃,b₁,b₂,b₃Setting value, re-execute Step G.
15. processing method according to claim 14, it is characterised in that, in such a way will be straight in the step 905 Matrix I (i, j) conversions in angular coordinate (i, j), will four points of (r, θ) surrounding to the matrix I (r, θ) in polar coordinates (r, θ) The weight of intensity add up and be assigned to I (r, θ), wherein：

(I) I (i, j) weight is (1- δ j) * (1- δ i)；

(II) I (i, j+1) weight is δ j* (1- δ i)；

(III) I (i+1, j) weight is (1- δ j) * δ i；

(IV) I (i+1, j+1) weight is δ j* δ i；

So I (r, θ)=I (i, j) * [(1- δ j) * (1- δ i)]+I (i, j+1) * [δ j* (1- δ i)]+I (i+1, j) * [(1- δ j)*δi]+I(i+1,j+1)*[δj*δi]。
16. processing method according to claim 13, it is characterised in that also include after the step H：

Step I：Symmetrization processing is carried out to the three-dimensional ion velocity focused image after the completion of fine setting, the symmetrization processing includes Following symmetrization handles at least one：Symmetrical above and belowization, symmetricalization, a quarter symmetrization.
17. processing method according to claim 16, it is characterised in that in symmetrical above and belowization, call above and below matrix Function is overturn to realize；In the symmetricalization operation, left and right upset function is called to realize.
18. the processing method according to any one of claim 1 to 17, it is characterised in that processing method is in matlab journeys Realized on sequence platform.