| 摘要 |
PURPOSE:To expose an original by moving and fixing a light source and an optical system within a prescribed range when adopting variable power, setting freely a variable power range, moving the optical system by fixing the original, or moving the original by fixing the optical system. CONSTITUTION:The first mirror 5a formed as one body with a light source of a position I 5a at the time of unmagnification is moved and fixed to a position V5a of a range which does not obstruct a movement of a projection lens 5c when adopting variable power. As a result, a stop position V5b of the second mirror 5b is not superposed on a position IV5c of the lens 5c of the time of a magnified exposure. Accordingly, by this movement and fixation, the variable power range is set freely, an exposure by an original scan is executed by moving the optical system by fixing the original, or moving the original by fixing the optical system, and an image can be formed on a photosensitive drum 6. |
