| 摘要 |
PURPOSE:To prevent attachment of developer to nonimage areas and to obtain a sharp developed image in a method of applying alternating voltage and DC bias voltage to a developing member and grid wires, allowing the developer to jump toward an electrostatic latent image, and thus developing said image, by gradually changing the distance between the grid wires and an electrostatic latent image bearing member as the member proceeds. CONSTITUTION:A high-frequency alternating voltage source 7 for applying voltage to grid wires 6 and that 10 for applying voltage to a developing roller 4 are same in phase but the source 10 is set higher in voltage than that 7. A toner (d) moves forward and backward in accordance with the alternating voltage between the roller 4 and the wires 6, forming a cloud state. The toner (d) opposite to the areas of an electrostatic latent image formed on a photosensitive drum 1 is attached by attraction to the image as the drum 1 rotates to develop the image. At that time, since the distance between the wires 6 and drum 1 is gradually set smaller as the drum 1 rotates, the toner (d) once attached to the drum 1 is stripped, and fogging is prevented. |
