CN102620670A - Method and device for measuring pixel pitch of image sensor on basis of line light source - Google Patents
Method and device for measuring pixel pitch of image sensor on basis of line light source Download PDFInfo
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Abstract
A method and a device for measuring pixel pitch of an image sensor on the basis of a line light source belong to the field of length, or width or thickness metering of the metering equipment field which is characterized by utilizing an optical method. The method for measuring the pixel pitch of the image sensor on the basis of the line light source includes that a linear image is obtained by targeting the line light source, the pixel pitch of the image sensor is acquired by calculating by using the equality of a practically- measured frequency when the modulation transfer function value reaches the minimum value for the first time with a theoretical cutoff frequency in a frequency domain. The device for measuring the pixel pitch of the image sensor on the basis of the line light source is located in the plane determined by an optical axis direction and a row direction or a line direction of the image sensor, the line light source is curved, any part of the line light source can be subjected to quasi focal imaging to the surface of the image sensor. By adopting the method and the device for measuring the pixel pitch of the image sensor on the basis of line light source, errors among results of a single measurement can be reduced so that repeatability of the measurement results can be improved.
Description
Technical field
Belonging to the employing optical means based on the image sensor pixel measurement method for distance of line source and device is the field that is used for gauge length, width or thickness in the metering outfit field of characteristic; Relating in particular to a kind of is target with the line source, utilizes line source to look like to come the measuring method and the device of measurement image sensor pixel spacing at frequency domain.
Background technology
The image sensor pixel spacing is the very important technical indicator in precision measurement field.For example; A size known target is passed through optical system imaging; As shared image sensor pixel number, and pel spacing is promptly known the size of target picture according to target; Be the merchant through the size and the target size of target picture at last, just can demarcate the lateral magnification of this optical system; In addition, piece image is carried out spectrum analysis, only know pel spacing, just possibly accurately obtain the frequency spectrum of this image.
Yet; The product description of a lot of imageing sensors has only provided the pixel dimension of imageing sensor, and has not provided pel spacing; Like the MV-1300UM type industrial digital camera of Shaanxi dimensional view picture, it is 5.2 μ m * 5.2 μ m that product description has only been given the size of pixel; The IR113 type non-refrigeration focal surface movement of Wuhan Gao De and for example, its pixel dimension is 25 μ m * 25 μ m, though provide fill factor, curve factor＞80% simultaneously, still can't obtain pel spacing according to a uncertain fill factor, curve factor numerical value.If the frequency spectrum that we utilize above-mentioned imageing sensor to go to demarcate the lateral magnification of optical system or obtain certain image, pel spacing must become technical bottleneck.So it is very important that the pel spacing of measurement image sensor seems.
One, image sensor pixel measurement method for distance background technology
For the measuring method of image sensor pixel spacing, what at first expect is exactly in theory, can utilize one to project to the linear image that image sensor surface and length can be known, divided by this linear image institute covered pixels number, obtains pel spacing.Under perfect condition, this method has following two characteristics:
1) pixel that line source is covered fully, its gray-scale value is as the benchmark gray-scale value.
The edge pixel that 2) can not cover fully for line source, according to the ratio of its gray-scale value and benchmark gray-scale value, judge can the cover part scale.
Yet this method but has inevitable disturbing factor, has a strong impact on the accuracy of measurement result.
1) if the pixel that covers fully is saturated; Then gray-scale value will keep 255 constant; Gray-scale value between edge pixel that can not cover fully and the complete covered pixels will no longer have proportionate relationship, and the ratio of edge pixel that line source covers is judged mistake will occur.
2) in the line source process for imaging; Be bound to the to have powerful connections influence of light, random noise and imageing sensor dark current receives the influence of these disturbing factors, can make the pixel that line source covers fully; Gray-scale value is also all inequality, will bring difficulty to the judgement of benchmark gray-scale value like this.
Though these shortcomings can increase the length of line source in theory, remedied through sharing error equally with more pixel, the length that increases line source also can be brought new problem:
1) for the big optical lens of distortion, increase the length of line source, may make the line source picture that serious deformation takes place on length, in this case, not only can not share error equally, and can make the error in judgement of number of pixels bigger on the contrary.
2) in the optical system debug process, can make imageing sensor that the target of same intensity under the different visual fields is had different responses.Increased the judgement of benchmark gray-scale value so again.
Have above-mentioned a series of problem just because of this method, therefore in actual mechanical process, this method seldom is used, and the substitute is another serial method.
In April, 2005; College of Military Engineering journal the 17th volume is published an article for No. 2 " pel spacing of measuring the ccd image acquisition system based on Joint Fourier Transformation ", and this piece article has been introduced a kind of utilization centrosymmetric two square target are carried out the method that twice Fourier transform method tried to achieve the image capturing system pel spacing.This method is centrosymmetric two square-shaped image of output on spatial light modulator at first, through the fourier lense imaging, obtain the power spectrum of this width of cloth image on the CCD surface | S (u, v) |
2, this power spectrum obtains the real power spectrum after amplifying p times through image capturing system | S ' (u ', v ') |
2To respectively | S (u, v) |
2Compose with real power | S ' (u ', v ') |
2Be presented at once more on the spatial light modulator, form images, scheme electric acquisition system once more through fourier lense and amplify, obtain respectively | S (u, v) |
2Power spectrum o (ξ, η) and | S ' (u ', v ') |
2Power spectrum o (ξ ', η '), here, o (ξ '; η ') and o (ξ η) is the center for brighter square, and symmetrical is darker relatively square pattern in the both sides, center, and o (ξ '; η ') through p after doubly amplifying be exactly o (ξ, η), therefore, o (ξ; η) shared image capturing system pixel count D be the shared image capturing system pixel count D ' of o (ξ ', η ') p doubly, so, can utilize the ratio of D and D ' to calibrate the enlargement ratio p of image capturing system; After the p value is confirmed, | S ' (u ', v ') |
2And o (ξ ', η ') can confirm in succession, just can obtain among the o (ξ ', η ') between two squares apart from d ', utilize d '/D ' to obtain the pel spacing of ccd image acquisition system at last.The shortcoming of this method is: o (ξ, η) and o (ξ ', η ') can not guarantee that all square just in time covers on the pixel of ccd image acquisition system just; And very greatly may be across two pixels; This judgement to D and D ' will bring difficulty, all occurs ± 1 error during judgement easily, thereby makes the calibration result of the enlargement ratio p of ccd image acquisition system have error; And then have influence on o (ξ '; η ') judgement of the spacing d ' of two specks in, owing to utilized d '/D ', so can make the judgement of ccd image acquisition system pel spacing have inevitable error.
In Dec, 2005, College of Military Engineering journal the 17th volume is published an article for No. 6 " the CCD pel spacing based on the circular hole Fraunhofer diffraction is demarcated ", and a kind of method of utilizing the Fraunhofer diffraction distribution plan to demarcate the CCD pel spacing introduced in this piece article.This method utilizes the directional light irradiation to place the circular hole at collimator objective focal length place, and at the Fraunhofer diffraction distribution plan of collimator objective surface formation circular hole, this distribution plan incides the picture that the CCD surface forms this Fraunhofer diffraction distribution plan through the parallel ejaculation of collimator objective.Diameter a according to circular hole; Incident light wave length λ; And collimator objective focal distance f; Can obtain central bright spot diameter L=1.22f λ/a in the circular hole Fraunhofer diffraction distribution plan, again according to the number N of the shared CCD pixel of diameter of central bright spot in the Fraunhofer diffraction distribution plan ', the pel spacing that obtains CCD is δ '=L/N '.The shortcoming of this method is: the edge that can not guarantee central bright spot just in time drops on the pixel of CCD; And very greatly may be across two pixels; This just brings difficulty to the judgement of the shared CCD number of pixels of central bright spot diameter N ' in the Fraunhofer diffraction distribution plan; Occur ± 1 error easily, make the judgement of CCD pel spacing have inevitable error.
In June, 2008; Photon journal the 37th volume is published an article for No. 6 " pel spacing that utilizes TFT-LCD pixel mechanism diffraction test ccd image acquisition system ", and a kind of principle and method of utilizing Thin Film Transistor-LCD (TFT-LCD) test ccd image acquisition system pel spacing introduced in this piece article.This method at first forms the object space signal through TFT-LCD; According to TFT-LCD pixel zone printing opacity, the lighttight characteristic in non-pixel zone; Can it be regarded as one by orthogonal two two-dimensional gratings that the cycle rectangular raster constitutes; Be placed on the front focal plane of fourier lense, then on the back focal plane of this fourier lense, can obtain the spectrum intensity distribution plan of two-dimensional grating.This frequency spectrum profile is multistage spectrum distribution form; Wherein, Areal coordinate initial point place is composed in being centered close to of zero level frequency spectrum; The distribution form of each senior frequency spectrum and width are identical with the zero level frequency spectrum, but intensity reduces rapidly with the rising of level time, according to m level frequency spectrum center to the distance of initial point do | m λ f/d|.Gather this two-dimensional grating spectrum intensity distribution plan through the ccd image acquisition system, and arrive the shared pixel count N of initial point according to m level frequency spectrum center
m, the pel spacing that can obtain the ccd image acquisition system does | m λ f/dN
m|.This method also has with the identical shortcoming of above prior art: can not guarantee that zero level frequency spectrum and m level frequency spectrum center just in time drop on the pixel of CCD, therefore, N
mCan occur equally ± 1 error, make the judgement of ccd image acquisition system pel spacing have inevitable error.In order to solve N
mThe problem that has ± 1 error has adopted a kind of method of averaging of repeatedly measuring in the literary composition, under the situation of not considering enlargement factor, the pel spacing of the ccd image acquisition system of trying to achieve is:
This method is alleviated N to a certain extent
m± 1 error problem.
In October, 2008; Photoelectric technology is used the 29th volume and is published an article for No. 5 " the CCD pel spacing based on double direction shear is interfered is demarcated ", and this piece article has been introduced and a kind ofly interfered the relativeness of two half-court widths of fringe to measure the method for ccd image acquisition system pel spacing through double direction shear.This method is through directional light irradiation wedge shape mirror W, and the reflected light on the forward and backward surface of wedge shape mirror W is because the effect of wedge shape mirror W forms the shearing of x axle forward, again through mirror M
1Reflection back transmission is crossed wedge shape mirror W and is imaged on the ccd detector, and the width of fringe of this shear interference striped is d
1=λ R/ (s+2n β R), wherein, d
1=N
1Q; Simultaneously, the transmitted light on the forward and backward surface of wedge shape mirror W is through mirror M
2Incide again after the reflection on the wedge shape mirror W, form the shearing of x axle negative sense, the width of fringe of this shear interference striped is d
2=λ R/ (s+2n β R), wherein, d
2=N
2Q.These two equations all are the equations about CCD pel spacing q, radius R, shearing displacement s, and these two equations are constituted system of equations, and the expression formula that can obtain ccd image acquisition system pel spacing is:
Wherein, λ is the wavelength of incident light wave, and n is the refractive index of wedge shape mirror W, and β is the angle of wedge of wedge shape mirror W, all can be given by calibration system; N
1, N
2Be respectively the pixel count of the adjacent shear interference ccd image sensor that width of fringe covers of the positive negative sense of x axle, through to N
1, N
2Measurement, can obtain ccd image acquisition system pel spacing q.The shortcoming of this method is: can not guarantee that adjacent stripes covers on the pixel of CCD just, therefore, N
1, N
2All can occur ± 1 error, make the judgement of ccd image acquisition system pel spacing have inevitable error.
More than the common trait of these four kinds of methods be:
1) forms a shape and the big or small figure that all can know in image sensor surface;
2) figure has tangible boundary characteristic;
3) boundary position of figure is thought in the center of graphic limit institute respective pixel.
Than desirable measuring method, the advantage of this serial of methods is:
1), and avoided through judging and the process of edge pixel can make this method can bear the influence of larger interference factor with the proportionate relationship of benchmark gray-scale value because avoided the judgement of benchmark gray-scale value;
2),, reduced for the requirement of image also in the judgement that does not influence the graphic limit position even image is in state of saturation to a certain extent.
But this method also has the problem of self:
For the judgement of number of pixels, can only be that integer is judged, the judgement of each side can exist ± error of 0.5 pixel, and two edges will exist ± error of 1 pixel, line source length is short more, and error will be big more.
Though these shortcomings can increase the length of line source in theory, remedied through sharing error equally with more pixel, the length that increases line source can be brought new problem equally:
1) for the big optical lens of distortion, increase the length of line source, may make the line source picture that serious deformation takes place on length, in this case, not only can not share error equally, and can make the error in judgement of number of pixels bigger on the contrary;
2) in the optical system debug process, can make imageing sensor that the target of same intensity under the different visual fields is had different responses.Increased the judgement of benchmark gray-scale value so again.
The drawback of existing method is for the big optical lens of distortion, to be not suitable under big visual field, measuring; And the measurement under the small field of view, therefore error is bigger between the single measurement result, makes the measurement result poor repeatability.
Two, image sensor pixel gap measuring device background technology
The field tests of international Patent classificating number G01M 11/02 optical property discloses forming of moving image modulation transfer function measurement mechanism by two patents of invention:
Patent No. ZL200810137150.1; At on 09 29th, 2010 Granted publication day; Patent of invention " dynamic target modulation transfer function measurement method and device "; Disclose a kind of moving image modulation transfer function measurement mechanism of high-accuracy multifunctional, also had the structure of light source, optical system and imageing sensor in this device, and be that light source arrives image sensor surface through optical system imaging equally.
Patent No. ZL201010252619.3; At on 01 11st, 2012 Granted publication day; Patent of invention " moving image modulation transfer function measurement mechanism " on the basis of a last disclosed device of patent, further defines the coupling scheme of optical lens in the device and the method for synchronization of measurement.
But the movement locus that these two characteristic feature of an inventions are light sources is perpendicular to the straight line of optical axis; For the optical system that the curvature of field is arranged, in the process of light source motion, will inevitably cause the out of focus of image; If these two the disclosed measurement mechanisms of invention are applied directly among the present invention; Can't overcome problem of image blurring and gradation of image value variation issue that out of focus causes, this problem can cause the locational skew of cutoff frequency, and the accuracy of measurement result is affected.
Summary of the invention
The present invention is exactly the problem that is not suitable for measurement in the small field of view scope to above-mentioned existing measuring method; And there is the problem of out of focus in existing measurement mechanism; Proposed a kind of image sensor pixel spacing frequency domain measuring method and device, this method can improve measurement result repeatability in the small field of view scope; This device can be eliminated the influence of out of focus to measurement result.
The objective of the invention is to realize like this:
Based on the image sensor pixel measurement method for distance of line source, step is following:
A. placing length at object space is the line source of h, and direction is parallel with image sensor line or column direction, and after the calculating line source was the optical system of β through lateral magnification, the line source picture in the theory movement displacement of image sensor surface was: d=h β;
B. the theory movement displacement d that obtains according to a step and line source picture frequency spectrum model MTF (f)=| sinc (π fd) |, obtain the cutoff frequency that the line source picture frequency composes and be: f=1/d;
C. imageing sensor forms images to line source, as initial point spread function image, and full line or the permutation information that the line source picture is expert at or is listed as is extracted, and as initial line spread function image, this initial line spread function image has n element;
D. remove line source and keep the imageing sensor time shutter constant, imageing sensor forms images to background, obtains interfering picture, and with the maximal value of gray-scale value in the interfering picture as threshold value;
E. c goes on foot the initial line spread function image that obtains; Gray-scale value is modified to 0 less than the gray-scale value that d goes on foot the pixel of gained threshold value; Obtain modified line spread function image, this modified line spread function image has the identical element number n of initial line spread function image that obtains with the c step;
F. the modified line spread function image that e step is obtained is 1 to carry out discrete Fourier transformation and delivery by spacing; Obtain initial modulation transport function image; This initial modulation transport function image has the identical element number n of initial line spread function image that obtains with the c step; Be n discrete spectrum component, be respectively M according to spatial frequency order from small to large
0, M
1, M
2..., M
N-1, at this in proper order down, it is M that the initial modulation transfer function values reaches the pairing modulating transfer function value of minimal value for the first time
i, footnote sequence number is i under it;
G. it is M that the cutoff frequency value f that obtains according to b step goes on foot the modulating transfer function value that obtains with f
iPairing spatial frequency values equates, that is: f=i/ (nl), and the pel spacing that obtains imageing sensor is: l=i/ (nf)=id/n=ih β/n.
Above-mentioned image sensor pixel measurement method for distance based on line source, c step, d step, e step replace with:
C '. imageing sensor forms images to line source, as initial point spread function image;
D '. remove line source and keep the imageing sensor time shutter constant, imageing sensor forms images to background, obtains interfering picture, and with the maximal value of gray-scale value in the interfering picture as threshold value;
E '. the initial point spread function image that the c ' step obtains; Gray-scale value is modified to 0 less than the gray-scale value that d ' goes on foot the pixel of gained threshold value; And full line or the permutation information that the line source picture is expert at or is listed as extracted; Obtain modified line spread function image, this modified line spread function image has the identical element number n of initial line spread function image that obtains with the c step.
Image sensor pixel gap measuring device based on line source; Comprise line source, optical system, imageing sensor; Described line source arrives image sensor surface through optical system imaging, and, in this device optical axis direction and image sensor line or the determined plane of column direction; Line source is bending, and accurate Jiao in optional position is imaged onto image sensor surface on the described line source.
The invention has the beneficial effects as follows:
1) measuring method of the present invention's employing is different from traditional spatial domain measuring method; This method is that target obtains linear image with the line source; Pairing frequency equated with theoretical cutoff frequency when the modulating transfer function value that in frequency domain, utilizes actual measurement to obtain reached minimal value for the first time, calculated the pel spacing of imageing sensor; When this characteristic make to adopt the short and small line source of length, can obtain higher cutoff frequency, thereby share the error of cutoff frequency equally, make that the error between the single measurement result is littler, and then improve measurement result repeatability;
2) measurement mechanism of the present invention's employing is in this device optical axis direction and image sensor line or the determined plane of column direction, and line source is bending, and accurate Jiao in optional position is imaged onto image sensor surface on the described line source; This characteristic makes the modulation transfer function curve that measures more near true curve, and the cutoff frequency position that actual measurement obtains is more accurate, can further reduce the error between the single measurement result, improves measurement result repeatability.
Description of drawings
Fig. 1 is based on the image sensor pixel gap measuring device structural representation of line source
Fig. 2 is based on the image sensor pixel gap measuring device optical planar circuit figure of line source
Fig. 3 is based on the image sensor pixel measurement method for distance process flow diagram of line source
Among the figure: 1 line source, 2 optical systems, 3 imageing sensors
Embodiment
Below in conjunction with accompanying drawing the specific embodiment of the invention is described in further detail.
Fig. 1 is the image sensor pixel gap measuring device structural representation based on line source, and figure is as shown in Figure 2 for its optical planar circuit; This device comprises line source 1, optical system 2, imageing sensor 3; Described line source 1 is imaged onto imageing sensor 3 surfaces through optical system 2; And; In this device optical axis direction and the determined plane of imageing sensor 3 line directions, line source 1 is bending, and accurate Jiao in optional position is imaged onto imageing sensor 3 surfaces on the described line source 1; Wherein, the lateral length of line source 1 is 1.526mm, and the lateral magnification of optical system 2 is 0.0557.
Based on the image sensor pixel measurement method for distance of line source, process flow diagram is as shown in Figure 3, and this method step is following:
A. placing length at object space is the line source 1 of h=1.526mm; Direction is parallel with imageing sensor 3 line directions; After calculating line source 1 was the optical system 2 of β=0.0557 through lateral magnification, the line source picture in the theory movement displacements on imageing sensor 3 surfaces was:
d＝h·β＝1.526×0.0557＝0.085mm；
B. the theory movement displacement d=0.085mm that obtains according to a step and line source picture frequency spectrum model MTF (f)=| sinc (π fd) |, obtain the cutoff frequency that the line source picture frequency composes and be:
C. 3 pairs of line sources of imageing sensor 1 imaging, as initial point spread function image, and the full line information that the line source picture is expert at extracts, and as initial line spread function image, this initial line spread function image has n=1280 element;
D. remove line source 1 and keep 3 time shutter of imageing sensor constant, the imaging of the 3 pairs of backgrounds of imageing sensor obtains interfering picture, and with the maximal value of gray-scale value in the interfering picture as threshold value, this threshold value is 10;
E. c goes on foot the initial line spread function image that obtains; Gray-scale value is modified to 0 less than the gray-scale value that d goes on foot the pixel of gained threshold value; Obtain modified line spread function image, this modified line spread function image has the identical element number n=1280 of initial line spread function image that obtains with the c step;
F. the modified line spread function image that e step is obtained is 1 to carry out discrete Fourier transformation and delivery by spacing; Obtain initial modulation transport function image; This initial modulation transport function image has the identical element number n=1280 of initial line spread function image that obtains with the c step; Promptly 1280 discrete spectrum components are respectively M according to spatial frequency order from small to large
0, M
1, M
2..., M
N-1, at this in proper order down, it is M that the initial modulation transfer function values reaches the pairing modulating transfer function value of minimal value for the first time
i, footnote sequence number is i under it;
G. it is M that the cutoff frequency value f=11.7647lp/mm that obtains according to b step goes on foot the modulating transfer function value that obtains with f
iPairing spatial frequency values equates, that is: f=i/ (nl) obtains the pel spacing of imageing sensor 3: l=i/ (nf)=id/n=ih β/n.
According to top thinking pel spacing has been carried out 100 times and measured, the measurement result that obtains is listed in the table below:
Above-mentioned image sensor pixel measurement method for distance based on line source, c step, d step, e step replace with:
C '. 1 imaging of 3 pairs of line sources of imageing sensor, as initial point spread function image;
D '. remove line source 1 and keep 3 time shutter of imageing sensor constant, the imaging of the 3 pairs of backgrounds of imageing sensor obtains interfering picture, and with the maximal value of gray-scale value in the interfering picture as threshold value, this threshold value is 10;
E '. the initial point spread function image that the c ' step obtains; Gray-scale value is modified to 0 less than the gray-scale value that d ' goes on foot the pixel of gained threshold value; And the full line information that the line source picture is expert at extracts; Obtain modified line spread function image, this modified line spread function image has the identical element number n=1280 of initial line spread function image that obtains with the c step.
Claims (3)
1. based on the image sensor pixel measurement method for distance of line source, it is characterized in that said method step is following:
A. placing length at object space is the line source of h, and direction is parallel with image sensor line or column direction, and after the calculating line source was the optical system of β through lateral magnification, the line source picture in the theory movement displacement of image sensor surface was: d=h β;
B. the theory movement displacement d that obtains according to a step and line source picture frequency spectrum model MTF (f)=| sinc (π fd) |, obtain the cutoff frequency that the line source picture frequency composes and be: f=1/d;
C. imageing sensor forms images to line source, as initial point spread function image, and full line or the permutation information that the line source picture is expert at or is listed as is extracted, and as initial line spread function image, this initial line spread function image has n element;
D. remove line source and keep the imageing sensor time shutter constant, imageing sensor forms images to background, obtains interfering picture, and with the maximal value of gray-scale value in the interfering picture as threshold value;
E. c goes on foot the initial line spread function image that obtains; Gray-scale value is modified to 0 less than the gray-scale value that d goes on foot the pixel of gained threshold value; Obtain modified line spread function image, this modified line spread function image has the identical element number n of initial line spread function image that obtains with the c step;
F. the modified line spread function image that e step is obtained is 1 to carry out discrete Fourier transformation and delivery by spacing; Obtain initial modulation transport function image; This initial modulation transport function image has the identical element number n of initial line spread function image that obtains with the c step; Be n discrete spectrum component, be respectively M according to spatial frequency order from small to large
0, M
1, M
2..., M
N-1, at this in proper order down, it is M that the initial modulation transfer function values reaches the pairing modulating transfer function value of minimal value for the first time
i, footnote sequence number is i under it;
G. it is M that the cutoff frequency value f that obtains according to b step goes on foot the modulating transfer function value that obtains with f
iPairing spatial frequency values equates, that is: f=i/ (nl), and the pel spacing that obtains imageing sensor is: l=i/ (nf)=id/n=ih β/n.
2. the image sensor pixel measurement method for distance based on line source according to claim 1 is characterized in that c step, d step, e go on foot and replace with:
C '. imageing sensor forms images to line source, as initial point spread function image;
D '. remove line source and keep the imageing sensor time shutter constant, imageing sensor forms images to background, obtains interfering picture, and with the maximal value of gray-scale value in the interfering picture as threshold value;
E '. the initial point spread function image that the c ' step obtains; Gray-scale value is modified to 0 less than the gray-scale value that d ' goes on foot the pixel of gained threshold value; And full line or the permutation information that the line source picture is expert at or is listed as extracted; Obtain modified line spread function image, this modified line spread function image has the identical element number n of initial line spread function image that obtains with the c step.
3. based on the image sensor pixel gap measuring device of line source; Comprise line source (1), optical system (2), imageing sensor (3); Described line source (1) is imaged onto imageing sensor (3) surface through optical system (2); It is characterized in that: in this device optical axis direction and imageing sensor (3) row or the determined plane of column direction, line source (1) is bending, and last accurate Jiao in optional position of described line source (1) is imaged onto imageing sensor (3) surface.
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Cited By (3)
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| CN102607444A (en) * | 2012-03-17 | 2012-07-25 | 哈尔滨工业大学 | Method and device for measuring space of pixels of image sensor by using linear light source |
| CN102620671A (en) * | 2012-03-17 | 2012-08-01 | 哈尔滨工业大学 | Method and device for measuring pixel pitches of image sensor by utilizing line light source |
| CN109974596A (en) * | 2019-04-28 | 2019-07-05 | 广东工业大学 | A kind of linear displacement measurement device |
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| CN102620671A (en) * | 2012-03-17 | 2012-08-01 | 哈尔滨工业大学 | Method and device for measuring pixel pitches of image sensor by utilizing line light source |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102607444A (en) * | 2012-03-17 | 2012-07-25 | 哈尔滨工业大学 | Method and device for measuring space of pixels of image sensor by using linear light source |
| CN102620671A (en) * | 2012-03-17 | 2012-08-01 | 哈尔滨工业大学 | Method and device for measuring pixel pitches of image sensor by utilizing line light source |
| CN102607444B (en) * | 2012-03-17 | 2014-07-16 | 哈尔滨工业大学 | Method and device for measuring space of pixels of image sensor by using linear light source |
| CN102620671B (en) * | 2012-03-17 | 2014-10-15 | 哈尔滨工业大学 | Method and device for measuring pixel pitches of image sensor by utilizing line light source |
| CN109974596A (en) * | 2019-04-28 | 2019-07-05 | 广东工业大学 | A kind of linear displacement measurement device |
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