| 摘要 |
PURPOSE:To enhance yield while also enabling the enhancement of a printing speed, by using a monolithic type light emitting diode array having a plurality of light emission part lines each having many LED's arranged thereto in one line. CONSTITUTION:Same horizontal scanning signals are supplied to a first light emission part line A and a second light emission part line B in a timely shifted state through a delay circuit by using an LED array in which two lines of light emission parts 21 are arranged. Even if a2 of the A-line is inferior and a place supposed to emit light by a first horizontal signal does not emit light, the light emission part b2 of the B-line emits light and, therefore, the predetermined part of a photosensitive drum is destaticized. It is similar when the A-line is well and the B-line is inferior. Because probability wherein the A-line and the B-line simultaneously become inferior is low, the yield of the array can be enhanced to a large extent. In addition, when all of the light emission parts are well, the printing speed of a printer can be doubled by simultaneously scanning the A-line and the B-line. |
