EP4133260A1 - Verfahren und inspektionseinrichtung zur optischen inspektion einer oberfläche - Google Patents
Verfahren und inspektionseinrichtung zur optischen inspektion einer oberflächeInfo
- Publication number
- EP4133260A1 EP4133260A1 EP21715496.2A EP21715496A EP4133260A1 EP 4133260 A1 EP4133260 A1 EP 4133260A1 EP 21715496 A EP21715496 A EP 21715496A EP 4133260 A1 EP4133260 A1 EP 4133260A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- pattern
- image
- lighting
- sequence
- image recording
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
- G01B11/25—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures by projecting a pattern, e.g. one or more lines, moiré fringes on the object
- G01B11/2518—Projection by scanning of the object
- G01B11/2522—Projection by scanning of the object the position of the object changing and being recorded
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
- G01B11/25—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures by projecting a pattern, e.g. one or more lines, moiré fringes on the object
- G01B11/2513—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures by projecting a pattern, e.g. one or more lines, moiré fringes on the object with several lines being projected in more than one direction, e.g. grids, patterns
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
- G01B11/25—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures by projecting a pattern, e.g. one or more lines, moiré fringes on the object
- G01B11/2518—Projection by scanning of the object
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
- G01B11/25—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures by projecting a pattern, e.g. one or more lines, moiré fringes on the object
- G01B11/2518—Projection by scanning of the object
- G01B11/2527—Projection by scanning of the object with phase change by in-plane movement of the patern
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
- G01N21/88—Investigating the presence of flaws or contamination
- G01N21/8806—Specially adapted optical and illumination features
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
- G01N21/88—Investigating the presence of flaws or contamination
- G01N21/8851—Scan or image signal processing specially adapted therefor, e.g. for scan signal adjustment, for detecting different kinds of defects, for compensating for structures, markings, edges
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
- G01N21/88—Investigating the presence of flaws or contamination
- G01N21/89—Investigating the presence of flaws or contamination in moving material, e.g. running paper or textiles
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
- G01N21/88—Investigating the presence of flaws or contamination
- G01N21/89—Investigating the presence of flaws or contamination in moving material, e.g. running paper or textiles
- G01N2021/8909—Scan signal processing specially adapted for inspection of running sheets
Definitions
- the invention relates to a method and an inspection device for the optical inspection of a surface of an object, as well as an advantageous use of the method and the inspection device.
- an illumination device of the inspection device is used to generate a pattern which is periodic over time during an image recording sequence and has different illumination patterns on the surface. In or during this image recording sequence, several images of the pattern are recorded on the surface by means of an image recording device of the inspection device.
- the method according to the invention is suitable for the optical inspection of reflective surfaces.
- Reflective surfaces within the meaning of the invention include both ideally reflective (i.e. reflective) surfaces and surfaces which, in addition to reflective properties, also have a certain scattering effect.
- the criterion for this is that a surface illuminated with a pattern (including a pattern projected onto the surface) can be optically recorded in an image.
- a method for inspecting surfaces that has been known for a long time is deflectometry.
- the image of the reflection of a known pattern on the surface is recorded by a camera and evaluated with a computer. Defects in the surface lead to distortions in the pattern on the surface, which are recognized. If the recording geometry and the pattern geometry are known, it can also be used to determine a 3D topography of the surface. Various methods such as this are known to those skilled in the art is carried out. These are assumed within the scope of the invention and are no longer described in detail.
- Processes that manage with one image have the advantage that they can also be used on a moving surface and thus initially appear more suitable for the inspection of, for example, web goods or in production processes.
- they have the disadvantage that they are more prone to failure or require a second, physically present pattern in the beam path.
- WO 98/17971 A1 for example, a method is known how the smallest beam deviations can be recognized and determined. Essentially, a stripe pattern is observed there with a camera. The method described manages with a single image because the camera's pixel grid is used as the second pattern will.
- this has the disadvantage that a very precise adjustment of the camera and pattern is required. In the industrial environment, for example, in production processes, this can hardly be achieved or not at a reasonable cost.
- the lighting device and the image recording device are arranged at the angle of reflection (each based on the surface normal aligned perpendicular to the surface in the reflection area).
- the reflection angle means that the marginal rays (ie the visual rays emanating from the edge of the image point) of the image point are reflected in the reflection points on the surface and mark the visible area of the lighting pattern (pattern area) in the image point.
- the reflection of the lighting pattern of the pattern on the surface is just imaged in the image points of the image recording device.
- the method can also be used for curved surfaces.
- the duration of the image recording sequence is selected to be so short that a sequence reflection area can be viewed as constant.
- the sequence reflection area is defined as the total surface area covered or captured by the reflection areas in the respective images from the image recording sequence.
- the total surface area covered by the reflection areas in the respective images from the image recording sequence results from combining all reflection areas of all individual images that were recorded during the image recording sequence into a common area, which is then referred to as the sequence reflection area.
- This surface area can then be viewed as at least approximately constant if the reflection areas of all images from the image recording overlap at least 40% or more, preferably at least 60%.
- these values are not to be understood as fixed values, but rather typical guide values that the specialist may need. can experimentally adapt to the respective conditions. In principle, the methods can be used well as long as the optical conditions mean that significantly less than one period length of the pattern is imaged on an image point.
- concave curvatures of the surface due to the concave mirror effect are used to map large pattern areas in one pixel.
- a range of 40% to 70% overlap should be sufficient, with an estimate of the surface normals (ie an estimate of the topology of the surface, a range of 60% to 80% overlap.
- an estimate of the surface normals ie an estimate of the topology of the surface, a range of 60% to 80% overlap.
- Occurring errors may also result in other areas that the person skilled in the art can determine and / or specify empirically by test measurements when setting up a corresponding inspection device based on the teaching of the invention.
- the invention proposes that the duration of the image recording sequence is chosen so that the images recorded within the image recording sequence are recorded so quickly one after the other that the displacement of the surface due to the movement of the object from the first image to the last image of the image recording sequence is so small that the reflection areas of the first image and the last picture as the same area a can be viewed on the surface.
- the duration of the image recording sequence is chosen so that the images recorded within the image recording sequence are recorded so quickly one after the other that the displacement of the surface due to the movement of the object from the first image to the last image of the image recording sequence is so small that the reflection areas of the first image and the last picture as the same area a can be viewed on the surface.
- the reflection area on the surface that is recorded in the image point (defined in the smallest resolution by a camera pixel or possibly by combining several camera pixels) is predetermined by the recording geometry (distance, recording angle) and the recording optics. Due to the arrangement of the recording device and the lighting device at the angle of reflection with reference to the surface normal, a change in the angle of one of the two devices must also be reproduced in the other device will. This makes changes in the angle of reflection comparatively expensive. The same applies to the changes in the recording optics. According to the invention, the size of the reflection area and / or the pattern area depicted in the reflection area can be varied or adjusted comparatively easily via the distance between the recording device and / or the lighting device. However, this also requires a change to the structure of the inspection device.
- the size of the image point can correspond to the pixel resolution of the camera (used as an image recording device). At a given distance from the camera and a given focal length of the camera, this represents the highest possible resolution. The higher the resolution of the camera, the smaller the reflection area assigned to a pixel on the surface and the smaller the defects that can be seen on the surface.
- One way of changing the size of the image pixel is to change the pixel resolution of the camera.
- the pixel resolution of the camera is - in the case of the digital image recording preferred according to the invention - predetermined by the photo chip used as the recording sensor of the camera, on which individual pixels (sensor pixels) which detect (integrate) the light falling on this pixel during the exposure time.
- the size of the image point can also be achieved by combining several sensor pixels of the camera into one image point.
- An image point can also be referred to as a pixel. Image pixels and sensor pixels are different, however, if several sensor pixels are combined into one image pixel.
- the setting of the size of an image point can take place by combining several pixels of an exception sensor (sensor pixel) of the recording device to form an image pixel.
- the number of combined pixels in the direction of movement of the object and transversely to the direction of movement of the object can be selected differently. It can be useful to increase the size of the reflection area in the direction of movement of the object, while accepting a lower resolution, in order to achieve a greater over-thinking of the reflection areas of the individual images in a respective image recording sequence. This increases the sequence reflection area in the direction of movement of the object. A higher resolution can be maintained across the board.
- a motion blur occurs along the direction of movement of the object. Because the camera integrates all of the light that occurs during an exposure in an image point (pixel of the image that does not necessarily coincide with a pixel of the recording sensor) during an image recording If this pixel falls, the observed surface is enlarged in the direction of movement that is mapped onto the one pixel. In relation to the moving surface (also referred to as the reflection area assigned to the image point), the image point appears elongated, so to speak. “Longitudinal” and “transverse” refer to the direction of movement and do not necessarily have to match the row and column directions of the cameras. With an oblique viewing angle, each pixel appears stretched at an angle in relation to the direction of the rows and columns of the camera.
- a further measure can be to set the duration of the image recording sequence when the method is carried out.
- the duration of the image recording sequence in other words the time required to record all images of the one image recording sequence, determines - at a given speed of movement of the object or the surface - how far the surface area corresponding to the reflection area of the first image extends to the recording of the last picture. This results in the size of the sequence reflection area and the overlap of the reflection areas of the individual images to be set according to the invention. Basically, the overlap is greater, the shorter the duration of the image recording sequence.
- the scanning frequency (defined as the frequency of successive image recordings) and / or the exposure time can be adapted.
- the shorter the exposure time the sharper the recorded image (reduction of motion blur) and the faster images can be recorded one after the other (sampling rate).
- the exposure time can be shortened by increasing the brightness of the pattern produced on the surface and / or by opening the aperture of the recording optics.
- the exposure time can be shortened by increasing the brightness or enlarging the aperture (usually defined in optics by smaller f-numbers). It is therefore sensible to use a lighting device with a high but dimmable light intensity.
- Suitable lighting devices can be built from individually dimmable LEDs which, when individually dimmed, enable the creation of a pattern and, when dimmed together, enable the overall light intensity to be set. In principle, it can be preferred to operate the lighting device with maximum light intensity and to reduce the exposure time until suitably exposed images are recorded.
- the sensitivity of the measurement can also be influenced by the choice of the illumination distance (at the same time also the viewing distance between the recording device and the sample) and the viewing angle. Larger distances as well as flatter viewing angles (i.e. flatter in relation to the surface; perpendicular to the surface would be maximally steep) lead to a higher sensitivity. Particularly in the case of partially reflective and partially diffusely reflective surfaces, a flat viewing and illumination angle between (e.g. ⁇ 30 °) and / or the greatest possible illumination distance can be selected. According to the invention, the greatest possible illumination distance can mean that an available space is used for the arrangement of the illumination device.
- the lighting distance distance between the lighting device and the surface
- the distance between the receiving device and the surface can be selected to be greater than the distance between the receiving device and the surface, with typical values in the range between 1 and 10 times, for example.
- the person skilled in the art will, if necessary, select the values experimentally adapted to the respective application, which corresponds to the basic teaching of the invention that smaller lighting and viewing angles and / or a larger lighting distance (between the recording device and the lighting device) reduce the sensitivity in many Cases increased.
- the aim of recording multiple images is to determine the phase of the pattern in order to identify the position of the known illumination pattern in a recorded image point. This can cause errors in the surface can be recognized by distortions of the pattern on the surface.
- three image recordings can be made, for example.
- the pattern can also be designed periodically symmetrically, and the images can be recorded asymmetrically, for example by varying the scanning or image recording frequency between different images within the same image recording sequence.
- An application preferred according to the invention provides for scanning with at least or exactly four images within the same image recording sequence.
- the pattern itself can, for example, be a brightness sinusoidal distribution that is recorded with the same scanning sequence in four different phase positions. From this, the phase of the pattern in each of the images can be precisely determined in a simple manner. For example, the phase shift between the phases in the image recording sequence of successive images can be just% of the period length of the pattern. However, other phase shifts between the images of an image recording sequence are also possible.
- the area of the illumination pattern (pattern area) visible in the image points during an image recording sequence can be viewed as constant as long as this pattern area still remains visible at all in the image point and the detected intensity of the pattern area does not change significantly. This can be assumed, for example, if the recorded intensity does not change by more than 10%, preferably by no more than 8%, and particularly preferably by no more than 4% during an image recording sequence, or another defined criterion is complied with. In principle, the criteria already explained above also apply here
- the reflection area In the case of a pattern transverse to the direction of movement, the reflection area also changes. However, because the pattern has the same intensity along the direction of displacement of the object, a change in the angle of reflection does not necessarily lead to a change in the intensity.
- the intensity measured in the image point remains the same as long as the image point captures the same pattern area and the pattern area captured in the image point does not shift transversely to the direction of movement due to a curvature of the surface.
- this difference can be taken into account, for example, in the previously described adaptation of the period length of the pattern as a function of the orientation of the pattern along or across the direction of movement of the object.
- the period length of the pattern for pattern along and across the direction of movement can particularly preferably be different.
- a known curvature of the surface of an object in a defined surface area to be inspected can also be used to establish suitable criteria in order to determine a non-defective surface to distinguish from a defective surface and / or to correct the deviation resulting from the known (expected) surface shape in the evaluation of the recorded images within the scope of the error detection.
- the recording device can be focused in such a way that the illumination pattern recorded in the image is out of focus.
- the recording device is not focused on the pattern, but on the surface or another defined point.
- the depth of field or depth of field can also be selected in a targeted manner according to the invention in order to depict the illumination pattern in the image in a blurred manner, but the surface in sharp focus.
- a sharp distribution of brightness is washed out.
- a sharp pattern consisting simply of alternating sharply defined light-dark areas can be mapped approximately as a sinusoidal brightness curve.
- a particularly simple lighting device can be used without the need for additional optical elements to generate the desired brightness curve.
- the brightness distribution becomes more blurred, which can have a positive effect, in particular in the case of curved surfaces and the associated effects, if displaced pattern areas are mapped onto the images recorded in one of the image recording sequences.
- the surface to be inspected is not ideally reflective, but reflects semi-diffusely. The reflection is directed, but it scatters in a relatively large solid angle, ie the bidirectional reflection distribution function BRDF (English. Bidirectional Reflectance Distribution Function) has a scattering lobe of medium width.
- BRDF English. Bidirectional Reflectance Distribution Function
- the surface must reflect enough that a pattern can be observed at all. With relatively few reflective surfaces, it is therefore advantageous to choose a viewing and lighting angle that is as flat as possible and to make the lighting distance large.
- the three-dimensional topography of the surface of the object is determined by means of deflectometric methods. If, as in the method proposed according to the invention, the recording geometry and the pattern geometry are known, a 3D topography of the surface can also be determined. There are various known ways in which this can be carried out. Deflectometry primarily determines the deflection of a light beam striking the surface by determining the point of the pattern on which a visual beam emanating from the camera (recording device) and reflected on the surface strikes. So it will be the Deflection of the line of sight determined, which depends on the surface normal at the corresponding point.
- the topography of the surface can be determined from the resulting normal field of the surface, for example by integration.
- FCCL foils Flexible Copper Clad Laminates
- FCCL foils usually have a thickness of up to about 100-150 ⁇ m and have, for example, a polyamide core (or generally a plastic foil) which is laminated on one or both surface sides with a copper foil.
- wrinkles can arise that should be known by the method proposed according to the invention.
- lamination folds 4 as shown schematically in FIG. 1
- inner folds 5 as shown schematically in FIG. 2.
- the inspection device When inspecting curved surfaces, such as painted containers or car bodies, the inspection device according to the invention is programmed according to a preferred embodiment, for example by means of a corresponding handling device, guided over the curved surface in such a way that the lighting device and the recording device are each at a reflection angle to the surface being held.
- the Inspektionseinrich device is moved relative to the mostly stationary object. This generates a relative movement of the object or object surface to the inspection device. This type of relative movement is also meant in this description when speaking of a moving object relative to the inspection device.
- the smallest, flat topographical defects that can interfere with the appearance or function of the surface are to be found on the curved surface. It is often helpful to also measure such defects in three dimensions, i.e. to determine the 3D topology of the surface and the defect.
- the invention also relates to an inspection device for the optical inspection of a surface of an object and its use for the applications described above.
- the inspection device is provided with a lighting device and a receiving device, which are aligned with one another in such a way that a visual ray emanating from the receiving device as a visual ray reflected on the surface hits the illuminating device when a surface normal that is perpendicular to the surface at the point of incidence of the visual ray the angle between the outgoing line of sight and the reflected line of sight just halved.
- the recording device and the lighting device of the inspection device are thus arranged at the angle of reflection with respect to the surface.
- the lighting device is designed to provide a temporally periodic pattern with different lighting patterns to generate, and the recording device is designed to record images of the pattern reflected on the surface synchronously with the generation of the lighting pattern during the image recording sequence.
- the inspection device also has a computing unit for controlling the inspection device and for evaluating the recorded images, a processor of the computing unit being designed to carry out the above-described method or parts thereof.
- the lighting device has individually controllable light elements in a row or matrix arrangement.
- the recording device can further preferably have a recording sensor for recording images imaged on the recording sensor via recording optics, the recording sensor having individual sensor pixels (camera pixels) in a row or matrix arrangement.
- the lighting device can, for example, be designed as a lighting line, which is preferably arranged transversely or longitudinally to the feed direction (direction of movement of the object or the surface relative to the inspection device).
- a lighting line as a row arrangement of individually controllable light elements can consist of many LEDs or LED modules arranged next to one another, which can be individually switched synchronously with the image recording.
- the periodic patterns required for the phase shift method are generated in rapid succession with the lighting device.
- the recording device can also be designed, for example, as a line camera which, if necessary, can also be constructed from several line camera modules arranged next to one another. In such an arrangement, the composite image field of the line camera is a line on the upper surface (the so-called scan line).
- This scan line can be perpendicular to the relative Be aligned in the direction of movement of the surface and also has a certain width in the direction of movement, which is very small compared to its length (running transversely to it) and which depends on the pixel resolution of the line camera.
- the lighting line can be so long (transverse to the direction of movement) that it covers the entire width of the web to be inspected (or of the desired inspection area on the surface) at the angle of reflection. If the camera and lighting are arranged at the same distance from the surface, the lighting line on each side must be about half a scan line width of a single line camera longer than the scan line observed by all cameras on the surface, with other Ab stand conditions longer or shorter accordingly.
- the width of the lighting line (in the direction of movement) can determine the maxima len surface angle that can still be measured with the arrangement. If the surface angle is greater than the maximum surface angle, the camera's line of sight reflected from the surface no longer falls on the lighting and the camera can no longer see anything.
- the method can also be used with area cameras (matrix arrangement). Then the scan line becomes the image field because the width in the direction of movement is much larger. The width of the lighting line in the direction of movement can also be increased accordingly.
- an illumination matrix can be used instead of the illumination line. This consists of many individual LEDs or LED modules that are arranged in several seamlessly joined lighting rows, all of which can be switched independently of one another, synchronized with the image recording. This means that the width of a lighting line can also be varied easily by inserting several lighting lines in switched in the same way.
- a lighting matrix not only can patterns be switched across the direction of the web, but also patterns along the direction of the web. This is advantageous because deflectometry methods primarily measure surface angles or normals, specifically in the direction of the periodic pattern. So if you use a lighting line you can only measure angles perpendicular to the direction of movement, with an illumination matrix you can measure all directions, preferably the two directions along and across the direction of movement.
- FIG. 1 shows, in a schematic sectional illustration, an object with a surface to be inspected with a first exemplary defect
- FIG. 2 shows, in a schematic sectional illustration, the object according to FIG. 1 with the surface to be inspected with a second exemplary defect
- 3a shows a plan view of the one inspection device according to an embodiment of the invention during the inspection of a flat surface
- 3b shows a side view of the inspection device according to FIG. 3a; 1 and 2 is as object 1, the surface 10 of which is to be checked by an inspection device according to the Invention, an FCCL film Darge provides, which serves as the starting material for printed circuit boards. It is a laminated film 1 which consists of three layers, a middle plastic film 3 as the middle layer, onto which copper foils 2 are laminated as outer layers. The upper surface 10 of the object 1 is typically checked for surface defects.
- lamination folds 4 (FIG. 1) and inner folds 5 (FIG. 2).
- laminating folds 4 the material has formed slight folds that were pressed flat again during the laminating process.
- Inner folds 5 arise from the fact that folds have formed in the inner plastic film 3, which folds have been laminated in.
- Fig. 3b shows a side view of an inspection device 9 with a lighting device 8 and a recording device 7.
- a periodic pattern 13 with different lighting patterns 130 is shown, which illuminates or illuminates the surface 10 of the object 1 ( see also top view according to FIG. 3a).
- the lighting pattern 130 has a brightness distribution 14.
- the pattern 13 is also produced on the surface 13.
- the recording device 7 records the pattern 13 on the surface 1 in an image.
- the recording device 7 comprises a recording sensor 11, which generates an image of many image points 12.
- Optical rays 15 emanating from the (each) image point 12 are reflected on the surface 10 by optics (not shown) of the recording device and strike the pattern 13 generated there as reflected rays 19 on the lighting device 8 Lines of sight 15, 19 are shown.
- the marginal rays go from the edges of the image point 12 and border on the surface 10 the reflection area 17 from. All lines of sight 15 which hit the surface starting at the pixel 12 in the reflection angle a are located in the reflection area 17 on the surface 10 and are also reflected in the reflection angle a from the surface as reflected lines of sight 19. You meet in the pattern area 18 on the lighting device 8, because according to the fiction, contemporary arrangement, the receiving device 7 and the lighting device 8 are arranged in the reflection angle ⁇ based on the surface 10.
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Abstract
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Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
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DE102020109945.2A DE102020109945A1 (de) | 2020-04-09 | 2020-04-09 | Verfahren und Inspektionseinrichtung zur optischen Inspektion einer Oberfläche |
PCT/EP2021/057217 WO2021204521A1 (de) | 2020-04-09 | 2021-03-22 | Verfahren und inspektionseinrichtung zur optischen inspektion einer oberfläche |
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EP4133260A1 true EP4133260A1 (de) | 2023-02-15 |
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EP21715496.2A Pending EP4133260A1 (de) | 2020-04-09 | 2021-03-22 | Verfahren und inspektionseinrichtung zur optischen inspektion einer oberfläche |
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US (1) | US20230140278A1 (de) |
EP (1) | EP4133260A1 (de) |
JP (1) | JP2023521175A (de) |
KR (1) | KR20230014686A (de) |
CN (1) | CN115398213A (de) |
BR (1) | BR112022020214A2 (de) |
CA (1) | CA3179520A1 (de) |
DE (1) | DE102020109945A1 (de) |
IL (1) | IL297164A (de) |
MX (1) | MX2022012556A (de) |
WO (1) | WO2021204521A1 (de) |
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DE102022133889A1 (de) | 2022-12-19 | 2024-06-20 | Isra Vision Gmbh | Verfahren zur optischen Inspektion eines Objekts und entsprechende Inspektionseinrichtung |
Family Cites Families (12)
Publication number | Priority date | Publication date | Assignee | Title |
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DE19643018B4 (de) | 1996-10-18 | 2010-06-17 | Isra Surface Vision Gmbh | Verfahren und Vorrichtung zum Messen des Verlaufs reflektierender Oberflächen |
DE10063293A1 (de) * | 2000-12-19 | 2002-07-04 | Fraunhofer Ges Forschung | Verfahren und Vorrichtung zur mehrkanaligen Inspektion von Oberflächen im Durchlauf |
DE102004033526A1 (de) | 2004-07-08 | 2006-02-02 | Universität Karlsruhe (TH) Institut für Mess- und Regelungstechnik | Verfahren und Vorrichtung zur Analyse zumindest partiell reflektierender Oberflächen |
CN101305601B (zh) | 2005-11-10 | 2011-03-30 | 奥比·奥马特和鲍姆加特纳两合公司 | 用于摄录图像的摄像机芯片、摄像机和方法 |
JP2010256021A (ja) * | 2009-04-21 | 2010-11-11 | Konica Minolta Opto Inc | フィルム表面欠陥検査装置、フィルム表面欠陥検査方法及び光学フィルムの製造方法 |
JP2011064482A (ja) * | 2009-09-15 | 2011-03-31 | Kurabo Ind Ltd | 高速三次元計測装置及び高速三次元計測方法 |
JP4685971B2 (ja) * | 2009-09-24 | 2011-05-18 | 株式会社ケー・デー・イー | 検査システム及び検査方法 |
DE102010021853B4 (de) | 2010-05-28 | 2012-04-26 | Isra Vision Ag | Einrichtung und Verfahren zur optischen Überprüfung eines Gegenstands |
JP5443303B2 (ja) * | 2010-09-03 | 2014-03-19 | 株式会社サキコーポレーション | 外観検査装置及び外観検査方法 |
DE102011117894A1 (de) | 2011-11-04 | 2013-05-08 | OBE OHNMACHT & BAUMGäRTNER GMBH & CO. KG | Vorrichtung und Verfahren zur optischen Formerfassung von bewegten Gegenständen |
JP6917781B2 (ja) * | 2017-05-31 | 2021-08-11 | 株式会社キーエンス | 画像検査装置 |
JP7003669B2 (ja) * | 2018-01-10 | 2022-01-20 | 株式会社アイシン | 表面検査装置、及び表面検査方法 |
-
2020
- 2020-04-09 DE DE102020109945.2A patent/DE102020109945A1/de active Pending
-
2021
- 2021-03-22 CN CN202180026475.6A patent/CN115398213A/zh active Pending
- 2021-03-22 KR KR1020227038758A patent/KR20230014686A/ko active Search and Examination
- 2021-03-22 EP EP21715496.2A patent/EP4133260A1/de active Pending
- 2021-03-22 MX MX2022012556A patent/MX2022012556A/es unknown
- 2021-03-22 WO PCT/EP2021/057217 patent/WO2021204521A1/de unknown
- 2021-03-22 CA CA3179520A patent/CA3179520A1/en active Pending
- 2021-03-22 BR BR112022020214A patent/BR112022020214A2/pt unknown
- 2021-03-22 IL IL297164A patent/IL297164A/en unknown
- 2021-03-22 JP JP2022562049A patent/JP2023521175A/ja active Pending
- 2021-03-22 US US17/917,812 patent/US20230140278A1/en active Pending
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WO2021204521A1 (de) | 2021-10-14 |
CA3179520A1 (en) | 2021-10-14 |
US20230140278A1 (en) | 2023-05-04 |
DE102020109945A1 (de) | 2021-10-14 |
BR112022020214A2 (pt) | 2022-12-13 |
JP2023521175A (ja) | 2023-05-23 |
CN115398213A (zh) | 2022-11-25 |
MX2022012556A (es) | 2023-01-11 |
KR20230014686A (ko) | 2023-01-30 |
IL297164A (en) | 2022-12-01 |
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