| 摘要 |
A method and an apparatus for selecting an amount of light to be irradiated for fog detection onto a photoreceptor from a density detecting device out of amounts of light for low density or for high density. A real original is illuminated by a predetermined amount of illuminating light, whereby a toner image corresponding to the real original is formed on the photoreceptor. Light of an amount for low density from the density detecting device is irradiated onto the toner image to acquire a first density data. Thereafter, a pseudo original is illuminated by the predetermined amount of illuminating light, whereby a toner image corresponding to the pseudo original is formed. Light of the amount for low density from the density detecting device is irradiated onto the toner image to acquire a second density data. The difference between the first and the second density data is compared with a predetermined threshold value. If the difference is less than the threshold value, the amount of light for low density is selected for fog detection. If the difference is not less than the threshold value, an amount of light for high density is selected.
|
