| 摘要 |
PURPOSE:To control the color registering in a multicolor printing press with high accuracy, by mounting a means for inputting a crisscross register mark as image data, a means for calculating the registering shift quantity between colors from the crisscross register mark and a means for performing the adjustment of registering corresponding to the registering shift quantity being calculated. CONSTITUTION:When a positional shift is generated in crisscross register marks 65-68, registering inferiority is considered to be generated. By emphasizing the gradation difference of black, blue, red and yellow by using a monochromatic sensor in a line camera and utilizing a color correction filter, the signal levels of image signals of black, blue, red and yellow are adjusted so that a white paper part becomes a value of about 200, a black part becomes a value of about 20, a blue part becomes a value of about 75, a red part becomes a value of about 110 and a yellow part becomes a value of about 150 and stored in buffers at every picture element. At first, the data of one line is read from one buffer and the change point of a signal level is detected at every pixel, and the number of times of falling, the signal level of the first falling pixel and the number of a falling pixel are stored. When registering shift is generated, the numbers of two falling pixels being stored are read and the operation is applied to calculate registering correcting quantity. Next, a correcting direction moving a plate cylinder is specified from the first falling signal level. |
