| 摘要 |
PROBLEM TO BE SOLVED: To reduce cost by using a single rotating polygon mirror and a single BD sensor for a plurality of laser beam generation parts in an image forming apparatus provided with a plurality of image carriers. SOLUTION: The image forming apparatus is provided with: a laser beam detection means which is located on the scanning path of a first laser beam and outputs a signal showing the detection of the beam when the laser beam is inputted; a first horizontal synchronization signal generation means which generates the first horizontal synchronization signal which serves as a reference for deciding the timing of the beginning of writing an image with the first laser beam by inputting the signal from the laser beam detection means; and a timing signal generation means for a second laser beam which generates a signal for deciding the timing of the beginning of writing an image with the second laser beam by delaying for a predetermined time by inputting the horizontal synchronization signal of the first laser beam. In this case, the delay time is n times an average period of the first horizontal synchronization signal when the deviation of the first and the second laser beams is n on the reflection face of the rotating polygon mirror. COPYRIGHT: (C)2006,JPO&NCIPI |
