Printed matter color quality detection method and system

Abstract

An embodiment of the invention discloses a printed matter color quality detection method and system. A color code and a positioning core which has a position setting relation with a pure color area in a printed matter are arranged in each image-text cycle of the printed matter. A photoelectric sensor in a first position sends a color code emergence signal to a processor when detecting that the conveyed printed matter have a color code. When the printed matter with the color codes moves to a second position, the processor triggers an image acquisition device for image acquisition and searches the positions of the positioning cores. The processor determines the position of a pure color area according to the position of the corresponding positioning core and calculates the position adjustment amount of a fiber optical spectrometer according to the position of the pure color area, and a motion control mechanism drives the fiber optical spectrometer to move to a designated position. When the detected printed matter moves to a third position, the fiber optical spectrometer performs optical spectrum acquisition, and optical spectrum data are converted into LAB data and then are compared with a standard value to obtain a detection result. The printed matter color quality detection method and system have high detection precision and detection efficiency.

Description

technical field [0001] The invention relates to the field of label printing, in particular to a color quality detection system for printed matter. Background technique [0002] In the online production process of printed matter, color deviation usually occurs due to factors such as ink imbalance, unsuitable pressure, bad ink roller, or deformation and wear of printing plate. Manually detecting the color deviation of printed matter is prone to visual fatigue, and the detection effect will be greatly reduced due to factors such as color difference, viewing angle, and light source brightness. This leads to a large amount of waste in the online printing process, seriously affecting production efficiency and Cost of production. Similarly, for the off-line color quality inspection of the printed matter, manual inspection will seriously reduce the detection speed and detection accuracy. At present, the printing industry usually uses spectrophotometers and industrial cameras for o...

AI Technical Summary

Problems solved by technology

However, the above two color detection devices have the following problems: (1) The spectrophotometer calculates the absolute value of the color according to the absorption spectrum.

With the continuous improvement of the transmission speed of printing equipment, more and more printed materials are transmitted per unit time, and the number of printed materials detected by the spectrophotometer per unit time is fixed, which directly limits the detection speed of printed materials to be detected

(2) In the prism spectroscopic 3CCD camera, only the color information of the red, green, and blue channels are synthesized, and the less color channels doom it to not have too high color detection accuracy

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