| 摘要 |
PURPOSE:To reduce size and cost and enable exposure of high reliability to be performed by controlling one or both of the running speed of an imaging optical system and the quantity of light of an exposure lamp thereby making exposure time product constant in a copying maching using a fluorescent lamp as an exposure lamp. CONSTITUTION:This is the method of controlling a motor 14 for running an imaging optical system 22, wherein at the time when the information of the original 20 is subsequently fed to a photoreceptor 24 along with travelling of the imaging optical system 22 the quantity of light is converted to voltage by the light quantity detector 10 provided near a fluorescent lamp 21 and this detection voltage is compared with the output of a reference voltage generator 11 in a differential amplifier 12. According to the output voltage of the differential amplifier 12, a motor driving circuit 13 is driven, by which the magnetic field current of the motor 14 is controlled. In this case, the output voltage of the reference voltage generator 11 is set in correspondence to the temperature at which the ambient temperature of the fluorescent lamp 21 becomes 35 to 40 deg.C, i.e., the quantity of light becomes maximum. |
