Device for high-resolution monitoring of color security features

Abstract

A device (1) for checking a colored security feature (2) on a beverage packaging (4) produced by means of a security ink, at least comprising: an illumination device (6) for broadband illumination of at least a portion of the beverage packaging (4) or the beverage packaging component, a camera device (8) for capturing a plurality of images of the colored security feature (2) of the beverage packaging (4) or the beverage packaging portion during illumination of the beverage packaging (4) or the beverage packaging component by means of the illumination device (6), wherein each of the images represents an amount of reflected light of a predetermined wavelength, wherein the wavelengths differ from one another, at least with regard to the images, by a respective predefined wavelength range and lie within a color change interval (14) of the security ink,and an evaluation device (12) for determining the amount of reflected light per captured image and for comparing a mathematical processing of the captured values with a reference criterion and for outputting a result value or result signal depending on the comparison, wherein the mathematical processing corresponds to the first derivative of a function generated from the captured values, wherein a result value describing the highest gradient of the curve defined by the values is determined for the comparison.

Claims

[1] Device (1) for checking a coloured security feature (2) produced by means of a security ink on a beverage packaging (4), at least comprising: a lighting device (6) for broadband illumination of at least a portion of the beverage packaging (4) or the beverage packaging component, a camera device (8) for capturing a plurality of images of the colored security feature (2) of the beverage packaging (4) or the beverage packaging component during illumination of the beverage packaging (4) or the beverage packaging component by means of the illumination device (6), wherein each of the images represents an amount of reflected light of a predetermined wavelength, wherein the wavelengths differ from one another at least with regard to the images by a respective predefined wavelength range and lie in a color change interval (14) of the security color, and an evaluation device (12) for determining the amount of reflected light per recorded image and for comparing a mathematical processing of the recorded values with a reference criterion and for outputting a result value or result signal depending on the comparison, where the mathematical processing corresponds to the first derivative of a function generated from the recorded values, where a result value describing the highest slope of the curve defined by the values is determined for the comparison. [2] Device according to claim 1, characterized by that the reference criterion defines a range of values or data that represents predetermined deviations from ideal reflection data. [3] Device according to claim 1 or 2, characterized by that the mathematical processing of the second derivative corresponds to a function generated from the recorded values. [4] Device according to claims 1 to 3, characterized by that the camera device (8) is designed such that the images can be recorded simultaneously or that the camera device (8) is designed such that the images are generated with a temporal offset of less than 200µs. [5] Device according to one of the preceding claims, characterized by that the lighting device (6) and the camera device (8) can be operated in dependence on one another. [6] Device according to one of the preceding claims, characterized by that at least the majority of the wavelengths detected with regard to the amount of reflected light lie in the color change interval (14), wherein in the color change interval at a first end (16) at least 80% of the light emitted in the corresponding wavelength is reflected and in a second end (18) less than 20% of the light emitted in the corresponding wavelength is reflected. [7] Device according to one of the preceding claims, characterized by that the first range end (16) is spaced from the second range end by at least 20 nm and preferably by at least 30 nm and particularly preferably by at least 40 nm, wherein the second range end (18) lies in the near-infrared range (NIR). [8] Device according to one of the preceding claims, characterized by that the plurality of images of the colored security feature (2) of the beverage packaging (4) or the beverage packaging part during illumination of the beverage packaging (4) or the beverage packaging component by means of the illumination device (6) are at least five images. [9] Device according to one of the preceding claims, characterized by that the beverage packaging (4) is a can. [10] Device according to one of the preceding claims 1 to 8, characterized by that the beverage packaging (4) is a bottle. [11] Device according to claim 10, characterized by that the bottle is a PET bottle. [12] Food packaging return device or food packaging printing device, at least comprising a device according to one of the preceding claims.

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