Apparatus and method for detecting sheet-like material

Abstract

This invention provides a device and method to test slice materials, wherein, the device comprises transmission device, irradiation device, and receiving device and information process device. The transmission device is to load and transmit slice materials; the irradiation device is to irradiate the light on the slice materials; the receiving device is to receive the diffused and reflected light from slice and to convert the relative light into relative test images; the information process device is to collect and process test images and to compare the tested images and mode to test slice material color printing quality.

Description

technical field [0001] The present invention relates to detection devices and methods, in particular to devices and methods for detecting sheet materials. Background technique [0002] The quality inspection device for color printing of sheet materials has high requirements on inspection accuracy and inspection speed. At present, only Switzerland's ORMA--GIORI-----DE LA RUE company has produced a large banknote color printing quality inspection machine Nota Save Check II in the world. However, the inspection method of this machine is to convert the tristimulus values ​​R (red value), G (green value), and B (blue value) of the image color into black and white grayscale J values ​​by the following formula, namely: [0003] J=KrR+KgG+KbB (1) [0004] In the above formula, Kr, Kg, and Kb are conversion coefficients respectively corresponding to red, green, and blue, which are set in different areas on the sheet. Thus, a color image can be converted into a black and ...

AI Technical Summary

Problems solved by technology

However, because of the loss of color information, attempting to reflect the color status with grayscale information has serious defects, that is, the chromaticity (such as hue and saturation) error of color printing cannot be checked; on the other hand, in order to make the above " "Black and white model" can partially reflect a certain chromaticity error phenomenon in color printing, so it is necessary to establish many inspection models for implementation. For this reason, it takes several months to establish a predetermined inspection algorithm model at the inspection site

The above-mentioned "black and white model" also has a serious disadvantage, that is, it is extremely sensitive to the use environment. For example, this "black and white model" is very sensitive to the color change of the lighting source and banknote paper, so white balance correction must be done at least three times a day during work. Work

Images