CN100340840C - Method and device for optical form measurement and/or estimation - Google Patents
Method and device for optical form measurement and/or estimation Download PDFInfo
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Abstract
The invention discloses a method for the optical form measurement and/or estimation of optically smooth, reflecting or optically rough surfaces is disclosed. The above is characterised by a combination of a photometric stereo method, a deflectometric method and a diffuser, whereby the regions on the diffuser surfaces have a planar coding.
Description
Technical field
The present invention relates to a kind of to object and the surface, particularly smooth surface carries out method and a kind of corresponding device thereof of optical form measurement and/or evaluation.Say that further the bright and clean optically roughness degree that is meant object is in the transition range between optically roughness face and the optically smooth face.The optically roughness face is meant that its roughness is much higher than wavelength of visible light (about 0.5 micron), and the roughness of optically smooth face is then far below above-mentioned wavelength.Because this specific character, optically roughness produces nondirectional diffuse reflection or transmission in the face of light.Here the object that can enumerate has paper, chalk, frosted glass etc.In contrast, the optically smooth face then directionally reflects or the transmission incident ray.It can generate the image of its surrounding environment.Here adducible have level crossing or curved mirror and polished metal surface and a glass surface (lens).
Bright and clean object is in these two transition range between extreme.This object is very important, because we can often run into it.The particularly industrial object of being made by metal, plastics and timber and other material all belongs to bright and clean object.The roughness that the industrial processes of these materials (as the powder die-casting of injection moulding, metal and the pottery of the cut of metal and timber, plastics etc.) is reached is generally several microns, is in the rate range of visible wavelength (about 0.5 micron).
Background technology
There is a series of optics 3D sensor to be used to measure the optically roughness face of scattering at present.Wherein most widely used a kind of method is the basis that is projected as with candy strip.On a direction to fringe projection, on another direction, then observe with video camera.Striped more or less distortion occurs according to the shape of observed object in video camera.Can restore the shape of object from the distortion of striped.The intensity of the striped of the candy strip of meeting projection more than three, and hypothesis usually becomes Sine distribution.
Among other numerous method, should be mentioned that the method, particularly stereo photometry of " recovering body form " (Shape from Shading) this class according to the image shading value, the present invention is based on these class methods.Thereby this method draws its shape by the brightness structure of body surface.To be elaborated below to this.
For the optics shiny surface, known method has the three-dimensional measurement method.Measuring a single surface configuration, as plane or sphere (mirror, lens etc.), mainly is to adopt interferometry.And, then adopt Hartmann's method (Hartmann-Verfahren) and Shack-Hartmann test (Shack-Hartmann-Test) for the deformation plane such as the aspheric surface shape of complexity.This method is that the deflection that one light pencil taken place on measured object is observed.Other method then is that one is observed by the raster grating pattern that body surface reflected or propagated.Grating is according to object surface shape appearance distortion more or less.Said method is contained by deflectometry.Their common ground is that they measure the deflection of light, draw surface configuration then therefrom.Deflectometry is based on reflection law or refraction law, and law has been described the relation between incident ray, surface normal direction and reflection or the transmitted ray.
But up to the present, how to measure the problem that is in the surface in the transition range between optically roughness face and the optics shiny surface and also do not have solution.The measuring method on above-mentioned two kinds of surfaces is also inapplicable in this case.Though people can use a kind of sensor to measure the uneven surface that occurs bright and clean point once in a while, this sensor just is not suitable for measuring when smooth surface occupies ascendancy with respect to diffuse scattering surface.On the other hand, concerning a kind ofly being used for the sensor of optically smooth face, particularly surveying the inclined to one side sensor,, want to make optical imagery clear just gruelling if the surface is too coarse.For example, it must guarantee still can see the fine structure of grating.Though use the method for sine streak lower,, must guarantee that also the structure of striped is in visible scope because the sinusoidal striped allows higher indistinctness to the requirement of surface quality.
That is to say, for be in the transition range, often appear at smooth surface on the industrial processes product, known optical sensor can not provide gratifying solution.
U.S. Pat 4,912,336 have described a kind of method and apparatus that uneven surface, even surface and smooth surface is carried out shape recognition.In this case, with a scatterer certain distance is arranged and is evenly distributed on the semicircle around this scatterer---the light source on the hemisphere preferably, thereby the irradiation of being opened continuously by scatterer produces so-called wide light source, is used to illuminate the body surface that is taken.Arrive this surperficial light beam video camera and analyzed that is reflected into.
Summary of the invention
Therefore, purpose of the present invention just provides a kind of method and a kind of corresponding device thereof that can avoid above-mentioned defective.
In order to achieve the above object, of the present invention being used for to the optically smooth face, the method that smooth surface or optically roughness face carry out optical form measurement or evaluation, with a kind of stereo photometry, an a kind of deflectometry and a scatterer (S) are combined, and plane coding is carried out in the lip-deep position of this scatterer by the shape of selective scattering body (S), make lip-deep each position of scatterer corresponding with a normal vector respectively, and backscattering brightness corresponding with each normal vector reflection and the brightness of camera review by body surface is corresponding and by the backscattered brightness of this scatterer (S), obtain the slope p (x of body surface, y) and q (x, y); According to the slope p of body surface (x, y) and q (x y) determines the shape of body surface.
As if the characteristics of this method are that it combines two kinds of methods known, that repel mutually by a special optical element, particularly a scatterer that is shaped.On the one hand, it relates to a kind of known stereo photometry.This method is used for diffuse surface, but is not suitable for smooth surface.On the other hand, it relates to and a kind ofly is used to reflect or the deflectometry on transmission surface.The range of application of these two kinds of methods is widened by this mode below used for optical elements: the total method by their be combined intos has reached good especially result on smooth surface.
Description of drawings
The present invention is described in detail below by drawings and Examples, wherein:
Fig. 1 is a kind of device disclosed, that measure with stereo photometry;
Fig. 2 is a kind of partial view of device disclosed, that measure with deflectometry;
Fig. 3 is the embodiment synoptic diagram of a device of measuring according to optical form measurement method involved in the present invention.
Embodiment
Stereo photometry belongs to one group and is called as the method for " recovering body form according to the image shading value ".These methods are to infer the shape of the object to be imaged according to the variation of brightness in the image.For example, when people observe the photo of a face, can change hardly, but still can find the variation of brightness though it is believed that the reflection coefficient of skin.Exactly, the generation reason of these variations is and since residing orientation, lip-deep some position make light that they send to video camera than other position send more.If light vertically is mapped on the surface from light source, it is maximum that brightness will reach, and when light nuzzled up the surface, brightness was minimum.The example of an image is exactly that the sun illuminates earth surface.In summer, noon sunlight almost is vertically to shine earth surface, and brightness is just very big.And at sunset, light nuzzles up from the surface just, and brightness at this moment is just very little.When recovering body form according to the image shading value, different thinkings can appear.
It is the shape that is used for measuring not with grain surface (surface reflection coefficient unanimity everywhere) that one group of methods is wherein arranged.And other method is also determined the position (determining light source according to the image shading value) of light source except the Measuring Object shape.The photometric stereo rule in contrast, the position of known luminaire in advance, and allow the surface to have texture.When relating to a kind of broad-spectrum sensor, this point is just noticeable especially, because in practice, in most cases and do not know whether the surface has texture.Therefore, then can describe stereo photometry.
Here earlier the stereo photometry of using on the device shown in Fig. 1 is described.At first, (x, testee G y) are successively by 1,2,3 irradiations of three point source of lights to have 3D shape z.In Fig. 1, the surperficial O of straight line directed towards object G.Under the simplest situation, people can suppose that the distance of light source is far and the illumination direction of each light source on object G is invariable.If surperficial O is lambert's scatterer (desirable non-directional scattering), situation just becomes particularly simple so.Under the situation of lambert's scattering, the scattering strength of object G only depends on the slope of irradiating angle and object G, and irrelevant with direction of observation.Video camera K is that in three light sources 1,2,3 each taken down image separately.In this course, the stationkeeping of object G and video camera K is constant.
In order to represent stereo photometry with mathematical measure, people need three illumination directions and be also referred to as target surface object G surperficial O normal vector n (x, y).Vector s
1, s
2And s
3The expression illumination direction.They point to each light source from target surface.
S
1＝(S
11，S
12，S
13)
T
S
2＝(S
21，S
22，S
23)
T
S
3＝(S
31，S
32，S
33)
T
Because the distance of light source is far, so the vector of being had a few on the surperficial O is near constant.In contrast, (x y) then according to the change of shape of surperficial O, and is counted as the local approach line vector to normal vector n.
n(x，y)＝(n
x(x，y)，n
x(x，y)，n
z(x，y))
T
Here supposition, surperficial z (x, y) differentiable and exist normal vector everywhere.(x, situation that y) can't differential can be divided into the surface some differentiable parts to make z owing to limit or teat.Video camera K takes the image E of object G down
1(x, y), E
2(x, y) and E
3(x, y), the light source of each image is respectively 1,2 and 3.Video camera K be on the z direction of principal axis and distance far, and each pixel picked-up illuminance E of incident down
i(x, y), i=1 wherein, 2,3, the coordinate of they and surperficial O (x, y) corresponding.According to Lambert law, the brightness of scattering is at illumination direction S
i(x becomes varies with cosine between y) with normal vector n.Also can select the brightness of representing scattering with the scalar product and the normal direction of illumination direction.The advantage of this method for expressing is that it concerns that the linear face of land illustrates with each.Except the slope and illumination direction of surperficial O, the brightness of scattering also depend on surperficial O (texture) local reflex coefficient ρ (x, y) and the brightness of light source and the optical parametric of video camera.The optical parametric of factor that all are constant such as light-source brightness and video camera is integrated on the length of illumination normal.Therefore obtain following equation:
E
1＝ρ· S
1· n
E
2＝ρ· S
2· n
E
3＝ρ· S
3· n
If the graphical representation method below introducing, that just can merge into an equation with these three equatioies by matrix representation.
E＝(E
1，E
2，E
3)
T
The illumination vector has formed each row of illumination matrix
So obtain following equation:
E＝ρ·S· n
Obtain by following formula
And
If the illumination vector is uncorrelated mutually on linearity, that is to say that if object G and three light sources 1,2,3 are not in one plane, the matrix S of then throwing light on is reversible.
Thisly by vector the mathematical description that stereo photometry carried out is compared with other describing mode (for example being described by angle), advantage is that it is at normal direction, illumination direction and brightness E
1, E
2And E
3Between set up a kind of linear relationship.According to the value of being tried to achieve, normal direction can be untied this relation: only need the illumination matrix inversion at an easy rate on mathematics.So just can finely find the solution not at grade the situation of three-dimensional lighting arrangements of normal direction and different illumination direction, and for other describing method (for example being described) by angle this be impossible.In addition, also very important for method this point involved in the present invention, because it equally also is to be described as the basis with vector, and therefore can considers to adopt three-dimensional lighting arrangements and measure three-dimensional body.If measured normal vector, can demonstrate target surface z (x, shape y) without difficulty by partial derivative p and q so according to x and y.(x, integration y) is also favourable for this shape z for the back.
Also effective to the description of stereo photometry to the far light source of Lambert surface and distance.This special circumstances can illustrate the function of this method as far as possible simply.At the light source of limited distance with do not meet the surface of Lambert law, can be with the method adjustment adapting to it, but here just no longer describe in detail.
Up to the present, the shape data of surperficial O have normal vector n (x, y) and partial derivative (being also referred to as slope local here)
(x y), must carry out integration with partial derivative in order to obtain shape z.
Except stereo photometry, the invention still further relates to deflectometry.The common ground of various deflectometries is that they measure the deflection of light on a reflection or transmission surface, draw surface configuration then therefrom.They are based on reflection law or refraction law, and law has been described the (see figure 2) that concerns between incident ray, surface normal and the reflection ray.Be a device that has video camera K among Fig. 2, the object G that camera alignment is illuminated by light source L is so that measure its surperficial O.Under the situation of reflection, incident ray E, reflection ray R and surface normal m are in same plane.The angle of incident ray and surface normal is identical with angle between reflection ray and the surface normal.We use from surperficial O, and the unit vector along light source L direction identifies incident ray, and similarly, we use from surperficial O, and the unit vector along observed ray b identifies reflection ray R, so just can make to describe to become simple.So, normal vector m just is the vector sum (unified specified length standard) of incident ray E and reflection ray R.
Up to now, deflectometry is applied on the optically smooth face always.Stereo photometry and deflectometry are conflicting outwardly because measured surface can not be simultaneously coarse be again smooth.If but using a kind of suitable optical element, so just these two kinds of methods can be combined well.Being combined in of these two kinds of methods hereinafter will be called as " luminosity deflectometry ".Here the optical element of being mentioned be a kind ofly have suitable shape, be preferably hemispheric, preferably be the transparent scatterer of rotational symmetric structure to small part.The homologue of the deflectometry part of the method is on the smooth surface of testee, and the homologue of photometry is in scatterer.According to integrated processes as described herein, can measure very bright and clean surface.
Fig. 3 is one and is used for the inclined to one side device of luminosity survey is carried out in reflection that its preferred construction mode is as follows: a video camera K aims at a tested bright and clean object G.Body surface O reflection ray, it is preferably semicircular scatterer S and towards the direction of video camera K from one.If the method is not in reflection but uses that video camera K must be from following aligning object G from opposite direction in the drawings then in transmission.Because self roughness, object G generates one clearly but the image of some fuzzy scatterer S more or less.Fuzzy image does not influence this method, just the situation of using in this case as deflectometry.Also will carry out deep discussion to this.Scatterer S itself then by some light sources 1,2,3 ... (being preferably 3) illuminated, as common in the photometry.Vector from one on the scatterer S representative some P to light source is respectively s
1, s
2, s
3Preferably, object G and light source 1,2,3 and spatially are three dimensional arrangement not at grade.
At first preferably open light source 1, and close other light source, and video camera K takes the image 4a of object G under this lighting condition down.Be opened and after other light source is closed, repeat a process at light source 2.To light source 3 grades also is like this.Image 4b, 4c etc. have been absorbed in this process.Also can select to open light source in proper order by another.Equally, light source also can be opened simultaneously, for example light source 1 and 2, be light source 2 and 3 then, be 3 and 1 at last.Be less than or also can adopt same way as more than the layout of 3 light sources.
After shooting, then image 4a, 4b, 4c are evaluated according to stereo photometry.As mentioned above, can draw from the gray-scale value of the picture point of the position of light source 1,2,3 and image 4a, 4b, 4c normal vector n (x, y) or the slope of scatterer S.
And
In common stereo photometry, it is the surface normal of object G, and in the luminosity deflectometry, it is the normal of scatterer S.A brand-new transformation is arranged here: stereo photometry is used to be encoded in lip-deep each position of scatterer.Coding can be divided into following a few step:
During the shape of ■ selective scattering body, should make lip-deep each position of scatterer that a normal vector n who only occurs is once arranged.It is a spheroid, an ellipsoid, a rotational symmetric object or their part preferably; Conversely,, on scatterer, have only a position, promptly concern one to one for each normal vector n.
■ follows, and with each corresponding backscattering brightness of scatterer surface normal vector n that is obtained by stereo photometry, and vice versa.
The reflection and the camera review brightness E of body surface passed through in backscattering brightness on the ■ scatterer again
1, E
2And E
3Corresponding one by one.
If the brightness of image E that lip-deep position of scatterer and normal vector n and the latter and backscattering brightness, backscattering brightness and video camera are taken
1, E
2And E
3Words one to one respectively, so the position just with brightness for corresponding one by one.According to this principle, just can the brightness from image derive on the scatterer position with light scatter.As long as by three illumination directions, each position on the scatterer just can be encoded in three dimensions, and obscuring can not appear in coding.The method that scatterer throws light on is compared as segmentation, substep with other, this coding has tangible advantage.The former must have a lot of illumination directions, but can only measure the single line on the scatterer, and this is equivalent to a kind of bidimensional to object and measures.
In contrast, in method involved in the present invention, just can carry out plane coding, thereby can carry out three-dimensional measurement object to scatterer with three illumination directions.Now from the normal vector of unique coding of position and scatterer derive body surface normal m (x, y).
m(x，y)＝(m
x(x，y)，m
x(x，y)，m
z(x，y)) T
Below a spherical scatterer S is described.Particularly a sphere has following characteristic: each the unit vector r from center towards surface direction (x, y) the parallel (see figure 3) of normal vector on (radial vector) and this aspect.Under the effect of reflection law or refraction law, radial vector and interknit (deflectometry) successively with the normal vector of object G.If to compare object G very little with the radius of ball, so all object points are positioned at the center of ball approx.Even be not the situation of this exception, also can calculate the normal vector on the object, but also will get a less object here, so that diagram becomes simple.When selecting the z axle of coordinate system, make it parallel with the optic axis of video camera K.According to reflection law, following formula be applicable to normal to a surface vector m (x, y)
m＝const·( n+ b)
Wherein, b is the unit vector towards observed ray, and the supplementary condition here is, m and n are unit vectors.So just can measure the normal vector of object G for the numerous points on the body surface O, obtain partial derivative p and q thus, and draw surperficial z (x, shape y) of object G again from them by integration.
Even but not to shape z (x, slope local p y) (x, y) and q (x y) carries out integration, also can draw the useful conclusion about body surface.Though still before carrying out integration, just interrupt passing judgment on contradicting, also be fine with desirable.In the application of many reality, the image of the gray level code of slope (intermediate result) shows even has precedence over z (x, y) image of (net result) shows.But because in any case net result is all more convincing than intermediate result, so above-mentioned situation is very astonishing.The image that same situation also occurs in the local approach line vector of body surface or its each several part shows.Exist between slope and the normal vector and contact directly, so that can replace the notion of " slope " hereinafter with the notion of " normal vector " or its each several part.
If surface configuration showed an observer (visual) and analyze its feature (explain, pass judgment on), the image of slope shows to have special advantage.Slope p (x, y) and q (x is with the output of the image format of gray level code on display, printer etc. y).Depression, projection, scuffing, burr or the like as can be seen in the image of slope shows.Also the form that at least one ingredient of slope local and/or local approach line vector is encoded with gray scale and/or color shadow can be shown.
The reason that slope replot looks like to have advantage is to be born with and to be good at analyzing the data of slope in people's vision sky.When the people is observing, can utilize brightness shade (in " recovering body form " and stereo photometry) to go to obtain a space image of observed object according to the image shading value.Also have other mechanism in addition, as stereopsis, it equally also can produce stereoeffect.Compare with other mechanism, slope observation is information source the most accurately.Well-trained observer can identify trickle irregular to 10 microns from shade under illumination that is fit to and suitable visual angle condition.Except shade, the reflection (as deflectometry in) of light on object or measured piece also can obtain spatial impression, can discern superfine little part by it.
If the gray-coded image of slope shows with using as the method for measurement slopes such as stereo photometry or luminosity deflectometry, the scrambling that on real-world object, can not discern of naked eyes even can become as seen so.For the people, the slope information of texture (local luminance) and object always can be obscured.Being typically, always being difficult on the judgment object one and seeming dark lines, is by a shape facility, causes as crackle, is still caused by the mark of a dark color.And luminosity deflectometry and photometric stereo rule can be offered help in this respect.They have considered not only a kind of lighting condition (with visual observation time different), thereby can distinguish slope data and texture.By after visual, naked eyes just can be seen those sightless features at the slope replot picture.
Even aspect degree of accuracy, the combination of slope measurement and slope replot picture also has many advantages.It can measure trickle details in some micrometer ranges.Slope is by visual, and simultaneously, hatching effect can be exaggerated and give prominence to by computing machine.
In addition, when object overturning and rotation occurred with respect to illumination, the slope measurement method can not be affected.For example, the observer can only one with respect to the completely specified direction of illumination on scrobicula trace on bright and clean object of identification.Similar situation also appears in many image processing methods.The selection of illumination is especially strict for smooth surface.In case with respect to illumination, the most tiny variation appears in the position of body surface, the inexactness during for example owing to introducing or the deviation of object itself, because different light reflects, the variation of essence will take place in appearance so.The luminosity deflectometry is then opposite fully.Even also can realize the repeatability of measuring on the bright and clean object that tilts evaluates with objective.In addition, slope replot looks like to be presented at and by equipment the aspect is evaluated on the surface automatically and had advantage.Treated slope data makes a kind of automatic evaluation become possible or more convenient, and this evaluation is preferably carried out on a computing machine or other electronics evaluation instrument.The advantage that slope replot picture described above shows all is applicable to automatic evaluation.
Have many-sided advantage because the slope replot picture shows, (x uses it in method y) also can to consider directly to measure shape z at other.Here, slope p (x, y) and q (x y) can obtain by numerical differentiation.But must consider the high frequency interference that all can have in the each actual measurement of the special reinforcement of differential meeting simultaneously.In the slope measurement method, particularly in luminosity deflectometry and the stereo photometry, then do not have this situation.Slope obtains through direct measurement in these methods.Disturb though it also is subjected to a spot of measurement, it has cancelled the step of the differential method that makes disturb worsens.
Thereby, a kind of measuring method and visual between preferred combination be exactly that slope measurement method involved in the present invention and slope replot picture show.
Should be mentioned that here a bit, promptly luminosity deflectometry itself just can be used for the optically roughness face.The image of the scatterer S that body surface provides can more or less blur.In other deflectometry, this point can be brought adverse effect, because they generally need structure meticulous figure such as striped, point etc. are carried out imaging.At the luminosity deflectometry then is not this situation.Luminosity on a spherical scatterer changes evenly, also distortion can occur hardly even make under the situation that image seriously blurs.
Therefore, on uneven surface and shiny surface, the luminosity deflectometry is better than other deflectometry.
On the other hand, it also is better than only being used for the stereo photometry of scattering surface.
Another advantage of this method is that three video cameras (according to three illumination directions) just enough can record the shape of object.Thereby once complete measurement can be controlled in the very short time, and this meets the industrial measurement and the requirement of inspection technology.If three light sources by by red, green and blue-coded and adopt a kind of electronic color video camera K to observe, so just can reduce to video camera only one.Chroma channel redness, green and blue comprising by image 4a, 4b, the 4c of the illumination direction of corresponding encoded.Certainly precondition is that object is monochromatic.To measure video camera and reduce to one, mean a critical progress.Even under the situation of the corresponding minimizing of irradiation time, take a picture similarly with the flashlamp in the photography, also can take down mobile object and serious motion blur phenomenon can not occur.
Up to the present consideration all is to be starting point to measure bright and clean object.In addition, said method and corresponding device thereof also can be used for scatterer.On this surface, the photometric stereo principle is not to show on the scatterer 1, but on one's body showing that object originally.Scatterer 1 forms row's expansion light source with light source 1,2,3 etc.The advantage of the light source that spatially is expanded is that they can be minimized the coherent optics noise that is caused by speckle.Coherent noise shows as the measuring uncertainty of shape on all optics 3D sensors.Thereby method described in the invention can reduce the measuring uncertainty of scatterer.In addition, this characteristic is also helpful to the accurate measurement of smooth surface.
What have advantage especially is that the result of shape measure is made into the form of computer documents for use.This is easy to they are done further processing.
In addition, when optical imagery, can use microscope and/or microcobjective.So just can replace or the existing optics decorum of additional video camera K, thereby also can measure the extra fine object surfaces.
Also can preferably adopt light emitting diode (LEDs) as light source.It makes simple, and is easy to operate direct.
At last, it is also conceivable that the one or more flashlamp of use throw light on.Like this, just can avoid possible measuring error by the of short duration fluorescent lifetime of flashlamp, particularly by the caused error of the relative motion between light source, video camera K and the testee, the relative motion here may be by being caused such as vibration or movement of objects.In addition, the advantage of flashlamp is exactly that luminous intensity is big, just can correspondingly reduce its light sensitivity like this when the design video camera.
Claims (34)
1. one kind is used for the optically smooth face, the method that smooth surface or optically roughness face carry out optical form measurement or evaluation, it is characterized in that, with a kind of stereo photometry, an a kind of deflectometry and a scatterer (S) are combined, and plane coding is carried out in the lip-deep position of this scatterer by the shape of selective scattering body (S), make lip-deep each position of scatterer corresponding with a normal vector respectively, and backscattering brightness corresponding with each normal vector reflection and the brightness of camera review by body surface is corresponding and by the backscattered brightness of this scatterer (S), obtain the slope p (x of body surface, y) and q (x, y); According to the slope p of body surface (x, y) and q (x y) determines the shape of body surface.
2. in accordance with the method for claim 1, it is characterized in that the shape of scatterer (S) is a spheroid, an ellipsoid, a rotational symmetric object or their part.
3. according to claim 1 or 2 described methods, it is characterized in that shape measure and/or evaluation results are made into the form of software document for use.
4. according to claim 1 or 2 described methods, it is characterized in that, use a kind of electron camera (K).
5. in accordance with the method for claim 3, it is characterized in that, use a kind of electron camera (K).
6. according to the claim 1 or the 2 or 5 described methods of front, it is characterized in that, use a kind of colour TV camera (K).
7. in accordance with the method for claim 3, it is characterized in that, use a kind of colour TV camera (K).
8. in accordance with the method for claim 4, it is characterized in that, use a kind of colour TV camera (K).
9. according to claim 1 or 2 or 5 or 7 or 8 described methods, it is characterized in that light source is by coloud coding.
10. in accordance with the method for claim 3, it is characterized in that light source is by coloud coding.
11. in accordance with the method for claim 4, it is characterized in that light source is by coloud coding.
12. in accordance with the method for claim 6, it is characterized in that light source is by coloud coding.
13. according to claim 1 or 2 or 5 or 7 or 8 or 10 or 11 or 12 described methods, it is characterized in that, reduce relevant speckle noise by an expansion, luminous scatterer surface.
14. in accordance with the method for claim 3, it is characterized in that, reduce relevant speckle noise by an expansion, luminous scatterer surface.
15. in accordance with the method for claim 4, it is characterized in that, reduce relevant speckle noise by an expansion, luminous scatterer surface.
16. in accordance with the method for claim 6, it is characterized in that, reduce relevant speckle noise by an expansion, luminous scatterer surface.
17. in accordance with the method for claim 9, it is characterized in that, reduce relevant speckle noise by an expansion, luminous scatterer surface.
18., it is characterized in that the slope local of body surface and/or local approach line vector are by visual and/or evaluated by electronic installation according to claim 1 or 2 or 5 or 7 or 8 or 10 or 11 or 12 or 14 or 15 or 16 or 17 described methods.
19. in accordance with the method for claim 3, it is characterized in that the slope local of body surface and/or local approach line vector are by visual and/or evaluated by electronic installation.
20. in accordance with the method for claim 4, it is characterized in that the slope local of body surface and/or local approach line vector are by visual and/or evaluated by electronic installation.
21. in accordance with the method for claim 6, it is characterized in that the slope local of body surface and/or local approach line vector are by visual and/or evaluated by electronic installation.
22. in accordance with the method for claim 9, it is characterized in that the slope local of body surface and/or local approach line vector are by visual and/or evaluated by electronic installation.
23. in accordance with the method for claim 13, it is characterized in that the slope local of body surface and/or local approach line vector are by visual and/or evaluated by electronic installation.
24. according to claim 1 or 2 or 5 or 7 or 8 or 10 or 11 or 12 or 14 or 15 or 16 or 17 or 19 or 20 or 21 or 22 or 23 described methods, it is characterized in that the slope local on surface and/or at least one ingredient of local approach line vector are by visual and/or evaluated by electronic installation.
25. in accordance with the method for claim 3, it is characterized in that the slope local on surface and/or at least one ingredient of local approach line vector are by visual and/or evaluated by electronic installation.
26. in accordance with the method for claim 4, it is characterized in that the slope local on surface and/or at least one ingredient of local approach line vector are by visual and/or evaluated by electronic installation.
27. in accordance with the method for claim 6, it is characterized in that the slope local on surface and/or at least one ingredient of local approach line vector are by visual and/or evaluated by electronic installation.
28. in accordance with the method for claim 9, it is characterized in that the slope local on surface and/or at least one ingredient of local approach line vector are by visual and/or evaluated by electronic installation.
29. in accordance with the method for claim 13, it is characterized in that the slope local on surface and/or at least one ingredient of local approach line vector are by visual and/or evaluated by electronic installation.
30. in accordance with the method for claim 18, it is characterized in that the slope local on surface and/or at least one ingredient of local approach line vector are by visual and/or evaluated by electronic installation.
31. in accordance with the method for claim 24, it is characterized in that slope local and/or local approach line vector are shown by the form with gray scale and/or color shadow coding.
32., it is characterized in that slope local and/or local approach line vector are shown by the form with gray scale and/or color shadow coding according to the described method of arbitrary claim in the claim 25 to 30.
33. in accordance with the method for claim 24, it is characterized in that at least one ingredient of slope local and/or local approach line vector is shown by the form with gray scale and/or color shadow coding.
34., it is characterized in that at least one ingredient of slope local and/or local approach line vector is shown by the form with gray scale and/or color shadow coding according to the described method of arbitrary claim in the claim 25 to 30.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2002158130 DE10258130A1 (en) | 2002-11-29 | 2002-11-29 | Optically rough surface photometric form determination procedure uses stereo photometry via scattering body with color coded illumination and color camera |
| DE10258130.4 | 2002-11-29 | ||
| DE10345349.0 | 2003-09-19 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1729381A CN1729381A (en) | 2006-02-01 |
| CN100340840C true CN100340840C (en) | 2007-10-03 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2003801070478A Expired - Lifetime CN100340840C (en) | 2002-11-29 | 2003-11-22 | Method and device for optical form measurement and/or estimation |
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| Country | Link |
|---|---|
| CN (1) | CN100340840C (en) |
| DE (1) | DE10258130A1 (en) |
Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102005022540B4 (en) | 2005-05-17 | 2007-07-05 | Siemens Ag | Method for minimizing image artifacts and medical imaging system |
| DE102005023165A1 (en) | 2005-05-19 | 2006-11-23 | Siemens Ag | Medical imaging system with a patient traversable part and collision protection method |
| US7711182B2 (en) * | 2006-08-01 | 2010-05-04 | Mitsubishi Electric Research Laboratories, Inc. | Method and system for sensing 3D shapes of objects with specular and hybrid specular-diffuse surfaces |
| DE102010007396B4 (en) * | 2010-02-03 | 2013-10-02 | Carl Zeiss Oim Gmbh | Method and device for optically inspecting a device under test with an at least partially reflecting surface |
| DE102010001715B4 (en) * | 2010-02-09 | 2023-08-24 | Robert Bosch Gmbh | Method and device for surface testing |
| US9818021B2 (en) | 2014-10-21 | 2017-11-14 | Isra Surface Vision Gmbh | Method for determining a local refractive power and device therefor |
| DE102014115331A1 (en) * | 2014-10-21 | 2016-04-21 | Isra Surface Vision Gmbh | Method and device for determining a three-dimensional distortion |
| CN104359417B (en) * | 2014-11-14 | 2017-02-22 | 西安交通大学 | Elliptical speckle generation method for large-viewing-field large-dip-angle measurement |
| CN108303045A (en) * | 2018-02-01 | 2018-07-20 | 北京科技大学 | A kind of surface roughness measuring method and device |
| CN109405770B (en) * | 2018-11-02 | 2020-12-25 | 上海华力微电子有限公司 | Method for monitoring level degree of glue coating tank of glue coating developing machine through thickness of photoresist film |
| CN110609039B (en) * | 2019-09-23 | 2021-09-28 | 上海御微半导体技术有限公司 | Optical detection device and method thereof |
| DE102021131620B4 (en) | 2021-12-01 | 2024-02-08 | Chromasens Gmbh | Photometric stereo method for scanning a surface, method for normalizing a scanning device for a photometric stereo method and scanning device for a photometric stereo method |
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| EP0047936A1 (en) * | 1980-09-17 | 1982-03-24 | Siemens Aktiengesellschaft | Method and device for the opto-electronic monitoring of superficiel structures on rotation-symmetrical bodies |
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| DE19944354C5 (en) * | 1999-09-16 | 2011-07-07 | Häusler, Gerd, Prof. Dr., 91056 | Method and device for measuring specular or transparent specimens |
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2002
- 2002-11-29 DE DE2002158130 patent/DE10258130A1/en not_active Ceased
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- 2003-11-22 CN CNB2003801070478A patent/CN100340840C/en not_active Expired - Lifetime
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0047936A1 (en) * | 1980-09-17 | 1982-03-24 | Siemens Aktiengesellschaft | Method and device for the opto-electronic monitoring of superficiel structures on rotation-symmetrical bodies |
| US4912336A (en) * | 1989-02-21 | 1990-03-27 | Westinghouse Electric Corp. | Surface shape and reflectance extraction system |
| JP2000097641A (en) * | 1998-09-28 | 2000-04-07 | Nireco Corp | Method for measuring hole or slip with transmission film |
| CN1253280A (en) * | 1998-11-05 | 2000-05-17 | 渡边正博 | Three-D shaped measuring device |
Also Published As
| Publication number | Publication date |
|---|---|
| DE10258130A1 (en) | 2004-06-17 |
| CN1729381A (en) | 2006-02-01 |
| DE10258130A8 (en) | 2005-03-10 |
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