| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a multicolor image forming apparatus capable of forming a high-quality image free from color shift or color change by constantly and accurately detecting and correcting misregistration even to the change with lapse of time of the position of a sensor which detects a line pattern. <P>SOLUTION: An image passing timing detection means 5 is constituted of a slit 157 and three photosensors 12. Each photosensor 12 has an LED element 154 for illumination, a photodetector 155 and a pair of condensing lenses 156. The line pattern 8 is detected through the slit 157 having an aperture 157a parallel with a main scanning direction, whereby errors in detection timing of the line pattern 8 associated with the variation (caused by vibration or temperature change or the like) of the attaching position of the photosensor 12 are drastically decreased. <P>COPYRIGHT: (C)2008,JPO&INPIT |
