| 摘要 |
PURPOSE:To simplify the device and to reduce the cost, by bringing the electrode row of an optical switch array having the multineedle electrode row, to which a voltage is applied, into contact with a toner layer and irradiating the optical image of a picture to the optical switch array. CONSTITUTION:An optical switch array 8 which is provided with a multineedle electrode row 6 and is connected to a power source 7 is arranged under a doctor 4, and an optical image 9 of a picture to be reproduced is irradiated to the optical switch array 8 to inject selectively the positive-polarity charge from the power source 7 to the negative charged toner layer on a donor roller, and thus, an electrostatic pattern corresponding to the optical image is formed. In the optical switch aray 8, the multineedle electrode row 6 is provided on an insulating substrate 10 so as to protrude slightly from the substrate 10, and a photoconductive insulator 11 is provided so as to cover the base part of the multineedle electrode row 6, and a transparent electrode 12 is provided on this insulator 11 in addition. Thus, the device is simplified, and the cost is reduced. |
