| 摘要 |
<p>An equal voltage is applied to a shielding case (11b) and a screen grid (28) when a normal mode is set, while a switch (46) is changed over to connect the shielding case (11b) to ground when a photo mode is set. Therefore, part of a discharge voltage from a corona discharger (11) is passed to ground in the photo mode. It is therefore possible to make the surface potential of a photosensitive body (10) in the photo mode in which the shielding case (11b) is grounded lower than that in the normal mode in which the shielding case (11b) of the corona discharger (11) is placed at a potential corresponding to an output direct-current voltage of a high-tension transformer (76). As a result, the halftones of photographs can be reproduced effectively.</p> |
