| 摘要 |
PROBLEM TO BE SOLVED: To form pattern images for color shift correction between pages without extending an interval between the pages, execute color shift correction processing, and thereby to reduce color shifts caused by a variation of a laser irradiation position, etc. accompanied by a temperature change.SOLUTION: A CPU40 causes an image forming part to form a color shift detection pattern 203 in each color between pages of a print job including images of a plurality of pages(S511), and corrects, on the basis of time Ty-Tk (S513) between a timing for outputting a sub-scanning writing timing synchronization signal, and a timing for detecting the color shift detection pattern 203 by a color shift detection sensor 25, time Trv, Tv from the timing for outputting the sub-scanning writing timing synchronization signal to a timing for laser light irradiation made by a laser unit 7 (S525, S526). |
