| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent photosensors from erroneously detecting a detection mark, in an image forming apparatus in which a toner image formed on an image carrier is transferred to a recording medium held and conveyed by a light transmissive transfer belt stretched between a plurality of support rollers, thereby obtaining a recorded image, and a detection mark formed on the transfer belt is detected by photosensors disposed opposite one support roller. <P>SOLUTION: Small diameter parts SD1 are formed in the support roller 16 which is disposed opposite the photosensors 20. Small diameter parts SD2 are formed in parts of the other support rollers 15, 17, and 18 which are opposite the belt mark formation areas MA. The depth of the small diameter part SD1 of the support roller 16 is less than the depth of the small diameter parts SD2 of the support rollers 15, 17, and 18. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
