摘要 |
<p>An electrostatic potential is induced onto an electrode from a photoconductive member such as a drum in accordance with the electrostatic potential of a background area of an electrostatic image on the drum. An intensity of light radiation of the drum is controlled in accordance with the induced potential. The light radiation may be radiation of a light image to form the electrostatic image or subsequent uniform radiation. The induced electrostatic potential may be used to control an exposure aperture means such as means defining a variable width slit. In another embodiment of the invention the electrode is in the form of an occluder plate and is positioned by electrostatic force to block the light radiation to a variable degree in accordance with the induced electrostatic potential.</p> |