| 摘要 |
PURPOSE:To make possible the transmission of the process controlling signal having no effect of noise by performing the light emission and reception for the purpose of optical detection by way of optical fibers and performing conversion to electric signals corresponding to the quantity of received light in a place having no effect of noise. CONSTITUTION:LED1, LED2, such as light emitting diodes, generate oscillation light by way of the driving circuits 31, 32 controlled by the input-output port 37 of a microcomputer unit 36. The oscillation light propagates in optical fibers 30A, 30C and radiates an encoder 22 and belt 29 corresponding to the driving of a photosensitive belt 29. The reflected light by this is received in the optical fibers 30B, 30D which assume a pair with the fibers 30A, 30C and is converted to pulse signals by the photoelectric transducers PD1, PD2 provided in a place where the effect of noise is less. The pulse signals are then added by an OR gate 35 and become the timing signal having no effect of noise through the port 37 only when the timing mark 29A on the belt 29 is detected. The interruption process by CPU according to this is then accomplished and the copying machine controlled well. |
