| 摘要 |
PURPOSE:To make the copying of many sheets repeatedly from the same latent image possible by passing the toner on a developing roller in the oscillating electric field generated by an auxiliary electrode provided just before the developing position. CONSTITUTION:A DC bias is applied by a power source 3 to the developing roller 2 which rotates by facing a photosensitive drum 1 and supplies a developer 4. The auxiliary electrode 5 is provided just before arrival of the roller 2 at the developing position (b) so that the toner on the roller 2 is passed through the inside of the oscillating electric field generated by a high frequency power source 6. The fogging on the white ground is thus decreased and the image density of fine lines is increased. There is no attenuation in the potential of the latent image even after repeated copying of many sheets from the same latent image. The deterioration of the gradation is thus prevented. |
