| 摘要 |
PURPOSE: To reduce the power consumption by controlling a voltage for lighting an exposing lamp so that the voltage when an original is read is different from that when the original is not read. CONSTITUTION: A controlling means 1 controls an exposing lamp driving means 3 and an optical driving means 2 so that a scanner part advances at a specified speed and the voltage for turning on the lamp required for image forming operation is simultaneously set to V1 in the case the position of a scanner part is OK by means of an optical HP(home position) detecting means 4. Next, when the means 1 detects that the scanner part means an image effective area by means of an image leading edge detecting means 8, the means 1 performs image forming operation equivalent to an area for an original size or for a paper size and performs moving equivalent to the scanner. The means 1 controls the means 3, so that the voltage for turning on the exposing lamp is lowered to the lowest voltage VL for turning on the lamp by which optical density and life are not disturbed after the scanner part performs scanning equivalent to the original size or the paper size and the image forming operation is performed. |
