EP3980761A1 - Method and device for optically inspecting containers - Google Patents
Method and device for optically inspecting containersInfo
- Publication number
- EP3980761A1 EP3980761A1 EP20711089.1A EP20711089A EP3980761A1 EP 3980761 A1 EP3980761 A1 EP 3980761A1 EP 20711089 A EP20711089 A EP 20711089A EP 3980761 A1 EP3980761 A1 EP 3980761A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- light
- camera
- different
- containers
- camera image
- 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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- 230000007547 defect Effects 0.000 claims abstract description 48
- 238000007689 inspection Methods 0.000 claims abstract description 44
- 238000005286 illumination Methods 0.000 claims abstract 3
- 230000005855 radiation Effects 0.000 claims description 20
- 230000003287 optical effect Effects 0.000 claims description 18
- 230000003595 spectral effect Effects 0.000 claims description 11
- 239000003086 colorant Substances 0.000 claims description 7
- 238000004458 analytical method Methods 0.000 abstract 1
- 230000010287 polarization Effects 0.000 description 12
- 239000000463 material Substances 0.000 description 9
- 230000000875 corresponding effect Effects 0.000 description 8
- 239000011521 glass Substances 0.000 description 8
- 238000010521 absorption reaction Methods 0.000 description 4
- 238000004049 embossing Methods 0.000 description 4
- 235000013361 beverage Nutrition 0.000 description 3
- 239000011159 matrix material Substances 0.000 description 3
- 241000196324 Embryophyta Species 0.000 description 2
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- 239000007799 cork Substances 0.000 description 1
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- 230000001419 dependent effect Effects 0.000 description 1
- 238000010017 direct printing Methods 0.000 description 1
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- 239000000945 filler Substances 0.000 description 1
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- 210000002643 mouth floor Anatomy 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 239000011049 pearl Substances 0.000 description 1
- 239000000825 pharmaceutical preparation Substances 0.000 description 1
- 229940127557 pharmaceutical product Drugs 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
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- 238000011144 upstream manufacturing Methods 0.000 description 1
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- 238000011179 visual inspection Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- 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
- G01N21/90—Investigating the presence of flaws or contamination in a container or its contents
-
- 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
- G01N21/90—Investigating the presence of flaws or contamination in a container or its contents
- G01N21/9018—Dirt detection in containers
-
- 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
- G01N21/90—Investigating the presence of flaws or contamination in a container or its contents
- G01N21/9036—Investigating the presence of flaws or contamination in a container or its contents using arrays of emitters or receivers
-
- 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
- G01N21/90—Investigating the presence of flaws or contamination in a container or its contents
- G01N21/9045—Inspection of ornamented or stippled container walls
-
- 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
- G01N2021/8845—Multiple wavelengths of illumination or detection
Definitions
- the invention relates to a method and a device for the optical inspection of containers with the features of the preamble of claims 1 and 7, respectively.
- Such methods and devices are usually used to inspect the container for foreign bodies and / or defects.
- the containers are transported to an inspection unit with a lighting unit and a camera so that they can be inspected in transmitted light or in incident light.
- the lighting unit emits light from a flat light exit surface, which light is transmitted or reflected via the container and then captured with the camera as at least one camera image.
- the at least one camera image is then evaluated for intensity information using an image processing unit in order to identify the foreign bodies and / or defects in the container.
- such methods and devices are used in the side wall, floor and / or fill level inspection of empty containers or containers that have already been filled with a product.
- the containers for the detection of foreign bodies are usually inspected with a diffusely radiating light exit surface in order to suppress, for example, glass embossing or water droplets in the camera image.
- the foreign bodies can be, for example, dirt, product residues, remnants of labels or the like.
- a directionally emitting light exit surface is used to detect defects in order to intensify the resulting refraction of light in the camera image.
- defects for example, damage to the containers, such as chipped glass, can be involved. It is also conceivable that the material is incorrectly produced, such as, for example, local material thickening.
- DE 10 2014 220 598 A1 discloses an inspection device for transmitted light inspection of containers with a device for subdividing the light exit surface into at least two predominantly horizontally separated sub-areas, which can be optionally switched on and off for side wall inspection and / or closure head inspection of the container.
- No. 6,304,323 B1 discloses a method for identifying defects in bottles.
- EP 0 472 881 A2 discloses a system and a method for optical inspection of the bottom surfaces of transparent containers.
- US 2008/0310701 A1 discloses a method and a device for visual inspection of an object.
- EP 0 926 486 B1 discloses a method for the optical inspection of transparent containers using infrared and polarized visible light.
- DE 10 2017 008 406 A1 discloses an inspection device with color lighting for inspecting containers for contamination and three-dimensional container structures.
- a radiation source has several spatially separate radiation zones which emit radiation in different wavelength ranges or with different intensities.
- a local color contrast arises, while in the case of soiling, only a local brightness contrast arises and no local color contrast.
- the object of the present invention is to provide a method and a device for the optical inspection of containers with which both foreign bodies and defects can be detected with less effort and which require less space.
- the invention provides a method for the optical inspection of containers with the features of claim 1.
- Advantageous embodiments of the invention are mentioned in the subclaims. Extensive investigations by the applicant have shown that the light emitted by the light exit surface passes through undamaged areas of a container predominantly with little or no deflection. In contrast, the light is refracted differently at the imperfections due to the associated local change in the container surface than at the intact areas. As a result, the light is deflected over the defect from a different emission direction of the light exit surface towards the camera than rich in the intact Be. Conversely, this is often less the case or not at all with foreign bodies, since contamination, for example, leads to local absorption of the light without significantly influencing the light path to the camera.
- the image processing unit evaluates the at least one camera image for the various wavelength ranges, a defect can be distinguished from a foreign body, for example due to a local change in the detected wavelength range. Conversely, the intensity information can still be evaluated in order to identify the absorption of the light by foreign bodies particularly well with the most diffuse radiation characteristics of the light exit surface. Consequently, with the method according to the invention, it is possible to identify both foreign bodies and defects with a single inspection unit. Because this is done with a single inspection unit, less installation space is required.
- the optical inspection method can be used in a beverage processing plant.
- the method can be upstream or downstream of a container manufacturing method, cleaning method, filling and / or closing method.
- the method can be used in a full bottle or empty bottle inspection machine.
- the method can be used to inspect returned returnable containers.
- the containers can be provided to hold drinks, food, hygiene articles, pastes, chemical, biological and / or pharmaceutical products.
- the containers can be designed as bottles, in particular as plastic bottles or glass bottles.
- Plastic bottles can specifically be PET, PEN, HD-PE or PP bottles. It can also be biodegradable containers or bottles, the main components of which are made from renewable raw materials such as sugar cane, wheat or corn.
- the containers can be provided with a closure, for example with a crown cork, screw cap, zip fastener or the like.
- the containers can also be present as empties, preferably without a closure.
- the method is used for side wall, floor, mouth, thread and / or content control of the container.
- Foreign bodies can be dirt, product residues, residues of labels and / or the like.
- damage to the containers, such as chipped glass can be a problem.
- material locations are incorrectly produced, such as, for example, local material thickenings or material tapering.
- the containers can be transported to the inspection unit as a container flow with a conveyor.
- the conveyor can comprise a carousel and / or a linear conveyor. It is conceivable, for example, that the transporter comprises a conveyor belt on which the containers are transported standing in an area between the lighting unit and the camera. Containers that hold one or more containers during transport (PUK) are conceivable.
- the container can also be transported held by side straps when e.g. B. the lighting illuminates the container bottom and the camera inspects the bottom through the container mouth.
- the lighting unit can generate the light with at least one light source, for example with a light bulb, a fluorescent tube or with at least one LED.
- the light can preferably be generated with a matrix of LEDs and emitted in the direction of the light exit surface.
- the light exit surface can be made larger than the camera view of the Benzol age. It is also conceivable that the light exit surface only illuminates part of the camera view of the container.
- An emission location can mean a local point or a flat section of the light exit surface here.
- a specific color spectrum portion of the light can be meant here by the wavelength range, for example. It is conceivable that the light exit surface emits the light from the emission locations in the different emission directions, each with a different wavelength or color. However, it is also conceivable that the wavelength ranges partially overlap. It is conceivable that the different wavelength ranges are emitted by correspondingly different light sources, in particular LEDs.
- the light can be visible Spectral range and / or in the non-visible Spectra I range of the wavelength spectrum are emitted herb.
- the light can be perceptible to the human eye in the visible spectral range and / or lie in a wavelength range of 380 nm-750 nm.
- the invisible spectral range can be imperceptible to the human eye and / or lie in the UV or IR wavelength range. It is also conceivable that the visible spectral range is combined with the non-visible spectral range.
- the light exit surface could emit the light for containers made of amber glass in the different emission directions with red and infrared wavelength ranges.
- the fact that "the light from emission points of the flat light exit surface is emitted in different directions with different wavelength ranges " can mean here that the light from a certain emission point of the flat light exit surface in one emission direction with a different wavelength range, in particular with another Color that is emitted than in a different direction.
- the camera can capture the at least one of the containers and the light transmitted or reflected through it with a lens and with an image sensor.
- the image sensor can, for example, be a CMOS or a CCD sensor. It is conceivable that the camera transmits the at least one camera image with a data interface to the image processing unit. It is conceivable that the light is generated by the lighting unit, then shines through the container and then captured by the camera.
- the camera can separate the wavelength range of the detected transmitted or reflected light for each image point of the at least one camera image. For example, it can be a color camera with which the different wavelength ranges, in particular colors, are recorded in at least two, in particular three color channels. For example, the color camera can include a Bayer filter to separate the colors.
- the image processing unit can process the at least one camera image with a signal processor and / or with a CPU and / or GPU. It is also conceivable for the image processing unit to include a storage unit, one or more data interfaces, for example a network interface, a display unit and / or an input unit. It is conceivable that the image processing unit evaluates the at least one camera image using image processing algorithms that are present as a computer program product in the storage unit.
- the wavelength ranges and / or an emission characteristic of the emitted light are adapted to a task, in particular to a type of container.
- boundaries of a region of the flat light exit surface with the radiation locations can be adapted to a container height and / or width.
- the area of the light exit surface that emits the different wavelength ranges in the different emission directions can be enlarged or reduced.
- multi-colored LEDs can be controlled differently depending on the task at hand.
- the light emitted by the light exit surface can be coded with a polarization property in addition to the mutually different wavelength ranges.
- the emitted light can also be locally coded with the polarization in addition to the direction coding with the different wavelength ranges.
- the camera can then separate both the different wavelength ranges and the polarization property in the at least one camera image.
- the polarization property can mean here that the light is emitted from the different emission locations of the light exit surface with different polarization directions in each case.
- a polarization filter with a continuously changing polarization profile or several polarization filters with different orientations can be arranged in the area of the light exit surface, so that the polarization of the emitted light changes locally.
- the camera separates the polarization property in the at least one camera image.
- it can comprise, for example, several image sensors each with a differently oriented polarization filter or a single image sensor with a polarization filter matrix.
- the camera can include a Sony IMX250MZR or IMX250MYR sensor for this purpose.
- the image processing unit evaluates the at least one camera image for the different wavelength ranges in order to additionally recognize local material embossing, such as embossings, glass embossing, pearls and the like on the containers and / or to differentiate them from the foreign bodies.
- material embossments can be used as decorative elements for example.
- the image processing unit can evaluate the at least one camera image for intensity information and the different wavelength ranges in order to identify areas with a changed wavelength range and changed intensity information as the container edge. Since both a darkening and a particularly large deflection of the light beams take place at the container edge, the container edge can thus be recognized particularly easily.
- the image processing unit evaluates the at least one camera image for a third local area with intensity information and wavelength range that differs from an environment in order to conclude that the container edge is present.
- the same wavelength range is emitted in at least one of the different radiation directions across all radiation locations. This allows the at least one camera image to be evaluated particularly easily, since the intact areas of the container are traversed predominantly in one direction of emission towards the camera and thus at least one camera image with only one of the wavelength ranges appears. Whereas the light is deflected by the flaws and appears with a different wavelength range in the at least one camera image. As a result, the defects can be distinguished particularly easily from the intact areas.
- the emission locations each have a different directional distribution with respect to the different wavelength ranges.
- a light beam from one of the different emission directions can be refracted at one of the flaws towards the camera, with another light beam from another of the different emission directions running towards the camera in the vicinity of the flaw.
- the image processing unit can evaluate the at least one camera image for a first local area with intensity information that differs from that of the surroundings in order to infer the presence of a foreign body. Because defects usually absorb light, they can be identified particularly easily via the differing intensity information in the at least one camera image.
- the image processing unit can evaluate the at least one camera image for a second local area with a wavelength range that differs from that of the surroundings in order to conclude that a defect is present. Because the flaw in the container deflects the light differently than the areas surrounding the flaw, it can be recognized particularly easily in this way in the at least one camera image. For example, the flaw in the at least one camera image can have a different color than its surroundings and / or undamaged areas of the container. This then suggests a different refraction of light than the environment and thus the defect.
- the at least one camera image can be separated into an intensity channel and a color channel with the image processing unit, the image processing unit recognizing the foreign bodies on the basis of the intensity channel and the defects on the basis of the color channel.
- the wavelength range can be one color.
- the at least one camera image in the HSV- Color space can be transformed, the H channel corresponding to the color channel and the V channel corresponding to the intensity channel.
- An intensity channel can mean a channel for a relative brightness, an absolute brightness or for an intensity.
- the invention provides a device for the optical inspection of containers with the features of claim 7 to solve the problem.
- Advantageous embodiments of the invention are mentioned in the subclaims.
- the lighting unit is designed to emit the light from the emission locations of the flat light exit surface in each case in the different emission directions with mutually different wavelength ranges means that, regardless of the intensity characteristics of the light exit surface, it can be determined for the pixels of the camera image whether the corresponding light component is through a defect has been deflected or whether it has passed through the intact areas of the respective container with little or no deflection.
- the image processing unit is designed to evaluate the at least one camera image for the various wavelength ranges, a defect can be differentiated from a foreign body, for example due to a local change in the detected wavelength range.
- the intensity information can still be evaluated in order to identify the absorption of the light by foreign bodies particularly well with the most diffuse radiation characteristic of the light exit surface. Consequently, it is possible with the device according to the invention to recognize both foreign bodies and defects with a single inspection unit equally well. Because this is done with a single inspection unit, less installation space is required.
- the device for the optical inspection of containers can be designed to carry out the method according to any one of claims 1-6.
- the device can accordingly comprise the features described above, in particular according to one of claims 1-6.
- the device for optical inspection can be arranged in a beverage processing plant.
- the beverage processing system can comprise container treatment machines, in particular a container manufacturing machine, a rinser, a filler, a closer, a labeling machine, a direct printing machine and / or a packaging machine. It is conceivable that the device for inspection is assigned to one of the aforementioned container treatment machines.
- the device can be used for full or empty bottle inspection. It is conceivable, for example, that the device is used to inspect returned returnable containers.
- the lighting unit can be designed to emit the light from the emission locations each with different colors in a visible spectral range. As a result, the lighting unit can be constructed with colored light sources that are used particularly frequently, in particular with LEDs, and is therefore particularly cost-effective.
- the light can be perceptible to the human eye in the visible spectral range and / or lie in a wavelength range from 380 nm to 750 nm.
- the camera can be designed as a color camera. As a result, the respective wavelength range can be recorded spatially resolved with little effort.
- the color camera can preferably comprise a Bayer filter for separating the colors.
- the lighting unit can each comprise a plurality of light sources with mutually different wavelength ranges for the emission locations. This allows the emitted intensity of the respective wavelength range to be set independently. Consequently, the lighting unit can be matched particularly easily to a transmission characteristic of the container, for example to its color.
- the lighting unit can comprise at least one lens, in particular a rod lens, Fresnel lens or lenticular lens, in order to bundle the light from the respective multiple light sources in the different emission directions for the emission locations.
- the lighting unit can be constructed in a particularly simple manner, so that it emits the light in the different emission directions with the different wavelength ranges from one another.
- the lighting unit comprise a plurality of lenses, in particular rod lenses, which are arranged next to one another along one direction in a uniform, linear grid.
- a rod lens can be understood here to mean a lens that comprises a linearly extruded lens profile.
- the lenses are arranged as a rectangular or hexagonal lens matrix.
- the lighting unit can include at least one white light source and a downstream bandpass interference filter in order to emit the light for the emission locations by interference in the different emission directions with the different wavelength ranges.
- bandpass interference filter a filter system with thin layers in the light wavelength range can be meant, which is designed to transmit a specific wavelength range in a radiation direction. Because the Layers of white light are passed through in different directions with a different optical path, they have a transmitting effect for correspondingly different light wavelengths.
- the lighting unit can comprise several light sources with different wavelength ranges from one another, in particular LEDs, with each light source being assigned a bundle optics to direct the light emitted by it onto a flat scattering element with a scattering angle of less than 20 °, in particular less than 15 ° to bundle.
- the lighting unit can be set up with a particularly small number of light sources, although the emitted intensity of the respective wavelength range can still be set independently.
- the flat scattering element can have a scattering angle of less than 10 °, in particular less than 5 °.
- the flat scattering element can be arranged along the flat light exit surface or form it.
- the flat scattering element can comprise a scattering film and / or a scattering disk.
- Figure 1 an inventive embodiment of a method for optical
- Figure 2 shows an inventive embodiment of a device for optical
- FIG. 3A shows a detailed view of the light exit surface of the lighting unit from FIG.
- FIG. 3B shows a detailed side view of the light exit surface from FIG. 3A with the different emission directions
- FIG. 4 shows a side detailed view of an exemplary embodiment of the lighting unit with lenses for radiating the different wavelength ranges in the different radiating directions;
- FIG. 5 shows a detailed side view of a further exemplary embodiment of the lighting unit with a band-pass interference filter for radiating the different wavelength ranges in the different radiation directions
- FIG. 6 shows a detailed side view of a further exemplary embodiment of the lighting unit with a diffuser for radiating the mutually different wavelength ranges in the different radiating directions
- FIGS. 7A-7B show a side view of the light exit surface and the camera from the figures
- FIG. 8A shows the camera image during the inspection of the foreign body and the defect according to FIGS. 7A-7B.
- FIGS. 8B-8C the intensity channel G and the color channel C of the camera image I from the figure
- FIG. 1 shows an exemplary embodiment according to the invention of a method 100 for inspecting containers 2 as a flow chart.
- the method 100 is explained in more detail with reference to FIGS. 2 - 6B:
- FIG. 2 an exemplary embodiment according to the invention of a device 1 for the optical inspection of containers 2 is shown as a perspective view.
- the inspection unit 10 With the lighting unit 3 and with the camera 4.
- the transporter 5 is arranged, which is designed here only as an example as a conveyor belt on which the container 2 in the direction R between the lighting unit 3 and the Camera 4 are transported (step 101).
- the containers 2 are transported on the conveyor 5 as a container stream and are each visually inspected between the lighting unit 3 and the camera 4.
- the lighting unit emits light from the flat light exit surface 30 in order to illuminate the container 2 (step 102).
- the emitted light is transmitted via the container 2 to the camera 4 (step 104).
- the arrangement of the lighting unit 3 opposite the camera 4 means that the light is reflected via the container 2.
- the camera 4 is arranged on the inspection unit 10 in such a way that it detects the containers 2 and light transmitted through them in at least one camera image (step 105).
- the lighting unit 3 is designed to radiate the light from the emission locations 31-42 of the light exit surface 30 shown in the following FIGS. 3A-3B in different emission directions A1, A2, A3 with mutually different wavelength ranges (step 103).
- the structure of the lighting unit 3 is explained below with reference to the execution examples in Figures 4-6 explained in more detail.
- the camera 4 is designed to capture the light in such a way that the various wavelength ranges can be distinguished from one another in the at least one camera image (step 106).
- the image processing unit 6 can be seen, with which the at least one camera image is evaluated for intensity information in order to identify foreign bodies and / or defects in the containers (step 107). This can be done, for example, with image processing algorithms known per se for recognizing local changes in the at least one camera image.
- the image processing unit 6 evaluates the at least one camera image for the various wavelength ranges in order to distinguish the flaws from the foreign bodies (step 108).
- FIG. 3A A detailed view of the light exit surface 30 from FIG. 2 is shown in FIG. 3A.
- FIG. 3B shows a detailed side view of the light exit surface 30 from FIG. 3A with the different emission directions.
- the various radiation locations 31-42 of the light exit surface 30 can be seen in detail, from which light with different wavelength ranges is emitted in each of the different radiation directions A1-A3.
- light is emitted from the emission locations 31-42 in the emission direction A1 in a green wavelength range, in the emission direction A2 in a yellow wavelength range and in the emission direction A3 in a red wavelength range.
- the light exit surface 30 is viewed from the opposite direction to the emission direction A1, it appears green, whereas it appears opposite to emission direction A2 yellow or opposite to emission direction A3 red.
- the same wavelength range is emitted in each of the different emission directions A1-A3 across all emission locations.
- the emission locations 31-42 each have a different directional distribution with respect to the different wavelength ranges.
- the wavelength ranges can be distributed continuously or in discrete steps over the emission locations A1-A3. It is true that in FIGS. 3A-3B individual areas for the emission locations 31-42 are shown purely graphically. However, it is also conceivable that the emission locations are distributed square or hexagonally over the light exit surface. In particular, the emission locations can form a continuum without being discretely separated from one another.
- the camera 4 is designed as a color camera in this exemplary embodiment.
- FIG. 4 shows a detailed side view of an exemplary embodiment of the lighting unit 3 with lenses L for radiating the mutually different wavelength ranges in the different radiating directions A1-A3. All that can be seen is a section with two light modules M 1, M2 arranged next to one another. Further light modules of the lighting unit are constructed accordingly and are not shown here in more detail. The illustration in FIG. 4 is only an example. It is conceivable that the lighting unit comprises only a single such light module M1.
- Each of the light modules M1, M2 comprises the light sources Q1-Q3 arranged next to one another and a lens L, which is designed here as a rod lens, for example.
- the light sources Q1-Q3 are of different types and emit light with different wavelengths from each other. For example, the light source Q1 emits light in a green, the light source Q2 in a yellow and the light source Q3 in a red light wavelength range.
- the light from the light source Q1 is bundled in the emission direction A1, the light source Q2 in the emission direction A2 and the light source Q3 in the emission direction A3 by the lenses L.
- light with different wavelength ranges can be emitted from each of the emission locations 31-42 in the different emission directions A1-A3.
- the lenses L are designed here, for example, as rod lenses, the Profilkon shown being extruded linearly perpendicular to the plane of the drawing. As a result, the lens has a focused refractive power only in the plane of the characters.
- a plurality of light sources Q1-Q3 can be arranged in a row, that is perpendicular to the plane of the drawing, next to one another in the longitudinal direction of the lens L.
- FIG. 5 shows a detailed side view of a further exemplary embodiment of the lighting unit 3 with a bandpass interference filter F for radiating the mutually different wavelength ranges in the different radiating directions A1-A3.
- the lighting unit 3 comprises several white light sources Q4, of which only two are shown here by way of example.
- the lighting unit 3 comprises only a single white light source Q4. They emit broadband light in a spectral range of 380nm - 750nm.
- the white light then passes through the downstream bandpass interference filter F in order to emit the light for the emission locations 31-42 by interference in the different emission directions A1-A3 with the different wavelength ranges.
- the bandpass interference filter F has a large number of thin layers, the thickness of which is in the spectral range of white light. Since the filter characteristic of such bandpass interference filters F is direction-dependent, the white light is transmitted in different colors depending on the emission direction A1-A3.
- FIG. 6 shows a detailed side view of a further exemplary embodiment of the lighting unit 3 with a diffuser ST for radiating the different wavelength ranges in the different radiation directions A1-A3.
- the lighting unit 3 comprises several light sources Q5-Q7 with mutually different wavelength ranges.
- these can be LEDs with different colors.
- a bundle optics 05-07 for example parabolic mirrors, is assigned to each of the light sources, in order to bundle the light emitted by the light sources Q5-Q7 onto the scattering element ST.
- the optical axis of the bundle optics 05 is in the direction of the emission direction A1, that of the bundle optics 06 in the direction of the emission direction A2 and that of the bundle optics 07 in the direction of the emission direction A3.
- the scattering element ST is provided, which fans out the light bundled or collimated by the bundle optics 05-07.
- the scattering element ST can for example comprise a scattering film.
- FIGS. 7A-7B show a side view of the light exit surface 30 and the camera 4 from FIGS. 2 and 3 during the inspection of a foreign body 8 and a defect 7.
- the detail D of FIG. 7A is shown in FIG. 7B.
- the planar emitting light exit surface 30 with the various emission locations 31-42 can be seen in a lateral profile.
- the light is radiated flatly in the direction of the camera 4 and thus shines through the container 2.
- the container 2 here consists, for example, of a transparent glass material, so that the light is transmitted through the container 2.
- the camera 4 comprises the image sensor 41 and the lens 42 in order to capture the container 2 in at least one camera image. It is conceivable that the camera 4 is designed as a color camera with a Bayer filter.
- the light beam S1 can also be seen, which, starting from the emission location 39 in the emission direction A2, illuminates the container 2. It hits the foreign body 8, which absorbs part of its energy. Consequently, the foreign body 8 appears in the at least one camera image of the camera 4 with a reduced intensity compared to its immediate surroundings. Because the foreign body does not deflect the light beam S1, it appears in the at least one camera image with the same wavelength range as its immediate surroundings.
- the light beam S2 can be seen, which, starting from the emission location 37 in the emission direction A2, illuminates the container 2 in the vicinity of the defect 7.
- the light is only absorbed to a small extent, depending on the material of the container 2, so that the corresponding image point appears in the at least one camera image with a high intensity and with the wavelength range of the emission direction A2.
- the light beam S2 passes through the container 2 at a point at which the container inner wall 22 and the container outer wall 21 run plane-parallel to one another. Consequently, depending on the angle of incidence, the light beam S2 experiences only a slight offset, but no change in direction. Consequently, the corresponding image point appears in the at least one camera image with high intensity and with the wavelength range of the emission direction A2. Consequently, the undamaged area of the container 2 appears in the at least one camera image with the wavelength range of the emission direction A2.
- the defect 7 has local notch surfaces 71, 72 on the container outer wall 21.
- This can be, for example, a notch due to a chipping. Consequently, the light beams S3, S4 are deflected at the local notch surfaces 71, 72 by light refraction. More precisely, the light beam S3 is emitted from the emission location 38 in the emission direction A1 and deflected towards the camera 4 by refraction on the first notch surface 71 as it passes through the container 2. In contrast, the light beam S4, starting from the emission location 34, passes through the container 2 in the emission direction A3 and is deflected at the second notch surface 72 towards the camera 4 by refraction. Accordingly, the defect 7 appears due to the local refraction of light at the notch surfaces 71, 72 in the at least one camera image with a different wavelength range from the surroundings, in particular a color.
- FIG. 8A shows a camera image I during the inspection of the foreign body 8 and the defect 7 in more detail. It can be seen that the container 2 appears in the camera image I in front of the light exit surface 30. It can also be seen that the foreign body 8 is shown as a darkened, first local area 8 '. In contrast, the defect 7 is shown as a second local area 7 'with an intensity similar to that of the immediate surroundings, but it appears there in the upper area with the color value C3 of the emission direction A3 and in the lower area with the color value C1 of the emission direction C1, since the Radiation, as shown in FIG. 7A, locally through the defect
- the undamaged areas of the container appear in the at least one camera image I. 2 as well as the environment U2 predominantly with the color value C2 of the emission direction A2.
- the foreign body 8 also only darkens the image information, but does not change the color value C2.
- the defect 7 appears with the color values C1 and C3 and can thus be distinguished from the foreign body 8 particularly easily with the image processing unit 6.
- the intensity channel G and the color channel C of the camera image I from FIG. 8A are shown in FIGS. 8B-8C.
- the image processing unit 6 shown in FIG. 2 initially divides the camera image I shown in FIG. 8A into the intensity channel G and the color channel C.
- the camera image I is divided into brightness values in intensity channel G and color values in color channel C, pixel by pixel, on the basis of an HSV color model.
- the image processing unit 6 then evaluates the intensity channel G of the camera image I for the first local area 8 ‘with intensity information that differs from the environment U1 in order to infer the presence of the foreign body 8. For example, this is done by means of a filter to detect fluctuations in brightness.
- the image processing unit 6 evaluates the color channel C of the camera image I for the second local area 7 'with a wavelength range that deviates from the surroundings U2.
- the local area 7 ‘of the defect 7 appears in the upper area with the color value C3 and in the lower area with the color value C1.
- the immediate surroundings U2 have the color value C2. Since the second local area 7 ‘has different color values C1, C3 than its surroundings U2, the defect 7 can come from the foreign body
- the image processing unit 6 After the detection of the foreign body 8 and / or the defect 7, the image processing unit 6 generates a signal that the container 2 has the foreign body 8 or the defect 7. On the basis of the signal, a switch can be controlled, for example, in order to channel the affected container 2 for renewed cleaning or recycling after the inspection.
- the image processing unit 6 evaluates the at least one camera image I for the various wavelength ranges, a defect 7 can be distinguished from a foreign body 8, for example due to a local change in the detected wavelength range.
- the intensity information can still be evaluated in order to identify particularly well the absorption of the light by foreign bodies 8 given the most diffuse radiation characteristics of the light exit surface 30. Consequently, it is possible with the method according to the invention to recognize both foreign bodies 8 and defects 7 with a single inspection unit 10 equally well. Because this is done with a single Inspektionsein unit 10, less space is required for it.
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Abstract
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DE102019208299.8A DE102019208299A1 (en) | 2019-06-06 | 2019-06-06 | Method and device for the optical inspection of containers |
PCT/EP2020/056019 WO2020244818A1 (en) | 2019-06-06 | 2020-03-06 | Method and device for optically inspecting containers |
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EP3980761A1 true EP3980761A1 (en) | 2022-04-13 |
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US (1) | US20220307987A1 (en) |
EP (1) | EP3980761A1 (en) |
CN (1) | CN114127545A (en) |
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DE102021115493A1 (en) * | 2021-06-15 | 2022-12-15 | Heuft Systemtechnik Gmbh | Process and device for full container inspection |
FR3132352A1 (en) * | 2022-01-28 | 2023-08-04 | Tiama | Methods and opto-computer systems for through-light inspection of a glass container |
DE102022102253A1 (en) | 2022-02-01 | 2023-08-03 | Heuft Systemtechnik Gmbh | Inspection device with multi-channel detection unit |
DE102022111523A1 (en) | 2022-05-09 | 2023-11-09 | Krones Aktiengesellschaft | Method and device for producing plastic containers with zone-by-zone inspection of plastic preforms |
Family Cites Families (26)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5095204A (en) | 1990-08-30 | 1992-03-10 | Ball Corporation | Machine vision inspection system and method for transparent containers |
US6067155A (en) | 1997-12-24 | 2000-05-23 | Owens-Brockway Glass Container Inc. | Optical inspection of transparent containers using infrared and polarized visible light |
EP1006350A1 (en) | 1998-11-30 | 2000-06-07 | Kirin Techno-System Corporation | Method for detecting defects in bottles |
DE19953738C1 (en) * | 1999-11-09 | 2001-06-07 | Krones Ag | Inspection device for side wall inspection of vessels |
DE10017126C1 (en) * | 2000-04-06 | 2001-06-13 | Krones Ag | Transparent container optical checking method, has illumination light field intensity and/or imaging sensitivity matched to individual container transparency |
DE60223956T3 (en) * | 2001-03-14 | 2011-05-19 | Hitachi Information & Control Solutions, Ltd., Hitachi | Examination device and system for the examination of foreign objects in containers filled with liquid |
DE10140009B4 (en) * | 2001-08-16 | 2004-04-15 | Krones Ag | Device for inspecting filled and closed bottles |
EP1779096B1 (en) * | 2004-07-30 | 2013-07-31 | Eagle Vision Systems B.V. | Apparatus and method for checking of containers |
NO322775B1 (en) * | 2004-09-24 | 2006-12-11 | Tomra Systems Asa | Device and method for detecting a medium |
DE102004054349A1 (en) * | 2004-11-09 | 2006-05-11 | Heuft Systemtechnik Gmbh | Checking the integrity of products in containers |
DE602005012163D1 (en) | 2005-09-09 | 2009-02-12 | Sacmi | METHOD AND DEVICE FOR THE OPTICAL INSPECTION OF A SUBJECT |
NL1031853C2 (en) * | 2006-05-22 | 2007-11-23 | Eagle Vision Systems B V | Method and device for detecting an unwanted object or defect. |
FR2907553B1 (en) * | 2006-10-24 | 2009-02-13 | Tiama Sa | METHOD AND DEVICE FOR DETECTING LOW AND HIGH CONTRAST DEFECTS IN TRANSPARENT OR TRANSLUCENT OBJECTS |
DE102009039254A1 (en) * | 2009-08-28 | 2013-05-08 | Krones Aktiengesellschaft | Apparatus and method for inspecting tagged vessels |
DE102010012570A1 (en) * | 2010-03-23 | 2011-09-29 | Krones Ag | Apparatus and method for inspecting filled containers for foreign bodies |
FR2958751B1 (en) | 2010-04-13 | 2012-05-25 | Iris Inspection Machines | METHOD FOR DETECTING DEFECTS IN GLASS ARTICLES AND INSTALLATION FOR CARRYING OUT SAID METHOD |
DE102012100987B3 (en) * | 2012-02-07 | 2013-07-11 | Miho Holding-Gmbh | Inspection device for objects e.g. containers, has cameras in which one camera images object in non-transparent state of optical element by performing transmitted light method |
FR2993662B1 (en) * | 2012-07-23 | 2015-05-15 | Msc & Sgcc | METHOD AND INSTALLATION FOR THE DETECTION IN PARTICULAR OF REFRACTANT DEFECTS |
FR3005354B1 (en) * | 2013-05-03 | 2015-05-15 | Msc & Sgcc | METHOD AND DEVICE FOR OBSERVING AND ANALYZING OPTICAL SINGULARITES USED BY GLASS CONTAINERS |
CN103743757A (en) * | 2014-01-21 | 2014-04-23 | 清华大学 | Device and method for detecting foreign matters on inner wall of glass bottle |
DE102014216188A1 (en) * | 2014-08-14 | 2016-02-18 | Krones Ag | Optical inspection method and optical inspection device for containers |
DE102014220598B4 (en) | 2014-10-10 | 2023-07-13 | Krones Aktiengesellschaft | Inspection device and method for transmitted light inspection of containers |
DE102016012585A1 (en) * | 2016-10-21 | 2018-04-26 | Seidenader Maschinenbau Gmbh | Device for detecting air bubbles in a container filled with liquid |
JP7084012B2 (en) * | 2016-10-31 | 2022-06-14 | キリンテクノシステム株式会社 | Foreign matter inspection device and foreign matter inspection method for containers |
US10422755B2 (en) * | 2016-12-07 | 2019-09-24 | Applied Vision Corporation | Identifying defects in transparent containers |
DE102017008406B4 (en) * | 2017-09-07 | 2023-07-20 | Heuft Systemtechnik Gmbh | Inspection device and method using color illumination |
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US20220307987A1 (en) | 2022-09-29 |
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