| 摘要 |
PURPOSE:To erase an excessive image precisely by a simple and small-sized structure by increasing the light of a reciprocating exposure lamp which forms an electrostatic latent image on a photosensitive substance in proportion to the moving speed of the lamp at its backward movement. CONSTITUTION:The exposure lamp 3 to be reciprocated along a platen 1 is provided with a variable speed mechanism for changing the moving speed of the lamp 3 itself and a means for changing the quantity of light and the light is increased at the backward movement increasing its moving speed and reduced when the speed of the lamp is low at the forward movement. Even if the exposing time is shortened at the backward movement of the lamp which increases the speed of the lamp, the quantity of light applied to the photosensitive substance 4 is increased as compared with that of forward movement, so that the potential of an excessive image formed on the photosensitive substance 4 can be reduced less than the background potential at the time of forward movement. Consequently, the potential of the photosensitive substance is reduced less than that of a developing roll and the excessive image is not developed. |
