Label pattern detection method and detection equipment

Abstract

The embodiment of the invention discloses a label pattern detection method and detection equipment. The detection method includes selecting a linear scanning area on the detection platform; using a plurality of linear luminous areas parallel to the linear scanning area and having adjustable luminous brightness to form a surface light source, and dividing the luminous surface of the surface light source into first light-emitting areas arranged in sequence. surface, the second light-emitting surface and the third light-emitting surface; the collection surface of the image acquisition device and the light-emitting surface of the surface light source are obliquely arranged on both sides above the linear scanning area, and the second light-emitting surface and the collection surface of the image acquisition device are linearly The longitudinal center of the scanning area is vertically symmetrical; the luminous brightness of the second luminous surface is adjusted relative to the luminous brightness of the first luminous surface and the third luminous surface, so that the background color of the label to be detected forms the gray scale of the image in the image acquisition device The difference between the gray scale of the decorative pattern and the image formed in the image acquisition device is kept within the set threshold range. The invention can greatly improve the accuracy of label detection.

Description

technical field [0001] The invention relates to the field of printed matter detection, in particular to a label pattern detection method and detection equipment using the method. Background technique [0002] A tag is a tool used to mark the classification or content of a target, making it easier for yourself and others to find and locate your target. Labels are widely used in the production or sale of commodities, such as cigarette labels, beverage packaging labels, alcohol labels, etc. At present, the most commonly used labels on the market are self-adhesive labels. In the label production process, in addition to printing the background color and the logo pattern with a high contrast with the background color on the label, decorative patterns will also be printed, such as laser shading with a grayscale smaller than the background color of the label, or a grayscale larger than the background Color bronzing patterns, etc. The decorative pattern not only makes the label ha...

AI Technical Summary

Problems solved by technology

The above two detection methods can reduce the false detection rate to a certain extent, but they will also miss a large number of real printing errors, which greatly reduces the detection accuracy

[0005] For decorative patterns (such as bronzing patterns) whose grayscale is much larger than the background color, the characteristics of the image collection are specular reflection and high reflectivity. The grayscale contrast between the collected decorative patterns and the background color of the label is very large. The image quality is obviously reduced, which will affect the final detection effect

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