| 摘要 |
<p>PURPOSE:To securely prevent drop of printing effect due to toner contamination of exposure plane, by gluing a transparent electret sheet to the exposure plane of an optical fiber cathode ray tube, and charging to the specified potential. CONSTITUTION:A transparent electret sheet 18 charged to a specified potential is glued to the exposure plane of a glass fiber plate 17 at the tip of an optical fiber cathode ray tube OFT 4. For this sheet 18, usually a thin teflon film is used, and is charged at high potential by means of a corona charger or the like. Necessary information is converted from electric signal to optical signal be means of the OFT 4, and is radiated to the surface of a photoreceptor 2. Contamination of the exposure plane of the OFT 4 by the toner slightly remaining on the surface of the photoreceptor 2 may be prevented by this charged sheet, so that clear printing may be obtained for a long period of time.</p> |
