| 摘要 |
PURPOSE:To improve the gradient of an electrophotographic image in a wide density area from low density to high density by irradiating a photosensitive body with a dot pattern by an eraser according to an original image. CONSTITUTION:The photosensitive body 28 is charged uniformly and electrostatically and an original O is lighted by a lamp 12 to irradiate the photosensitive body 28 with its original image, thus forming an actual electrostatic latent image. Further, the original light image is formed on a solid-state image sensor 18 and converted into an electric signal. Then, the photosensitive body 28 is irradiated with the dot pattern by the eraser 32 according to the read original image. Then, the rate of erasure by the eraser 32 is increased in proportion to original density X when X is in a low-density area, decreased linearly with X when in an intermediate density area, and made substantially continuous when 0<=X<=1.5, and the erasure rate is substantially 0 when X=0 or when X=1.5; and the largest erasure rate is determined almost corresponding to the quantity of exposure of a density part whose image density is 0.6-0.8 during image exposure. |
