| 摘要 |
PURPOSE:To expose plural reference patterns, and to detect them by a single detector, by switch-controlling plural reference patterns on a moving member instead of movement of an exposure optical system. CONSTITUTION:A mask plate 6 which is like a band and has a rectangular transparent window in the center is provided on the surface of the end part of an original placing plate in the right end of a platen 4. On this window, a circular arc plate-like moving member 8 is stuck to the tip part of an indicating pointer 9a of a moving coil type indicating instrument 9. On this moving member 8, a reference pattern of five blocks is formed. On this reference pattern, white and black are provided, respectively. A reference pattern image is exposed on the drum, is detected by a detector, this reference pattern input signal is compared with a prescribed reference value, is processed, a toner replenishing signal is outputted, and a toner replenishing device is driven. |
