| 摘要 |
PURPOSE:To enable a large number of same copies to be made at high speed, by injecting charge to the center or central layer of a composite semiconductor on a conductive substrate, illuminating the composite semiconductor with light, applying toner to it in accordance with charge captured, and transferring the toner to the surface to be printed on. CONSTITUTION:A composite photosensitive semiconductor 1 is formed on a conductive substrate 2, and consists of a semiconductor layer 3, an insulating or semiinsulating layer 4, a charge capturing central layer (hence TL) 5, and an insulating layer 6 each laminated in succession. An electric field is applied between the substrate 2 and an electrostatic charge generating source on the semiconductor 1, and positive charge is captured through the surface of the semiconductor 1 with TL 5. Light 10 is projected locally, releasing the positive charges on regions 7, 7', 7'' to the conductor 2. Negative electrons neutralize the positive charge in TL 5 or on the surface to selectively distribute on the semiconductor 1. The charge on the surface is erased by attaching and removing toner, but the charge in TL 5 remains as it is, permitting high speed copying without requiring charging and destaticizing at each time one copy is made during multiple copying. |
