Method of adjusting density detecting device used for image forming

Abstract

A method and an apparatus for setting an amount of light to be irradiated onto a photoreceptor from a density detecting device precisely in a short time in detecting the density of a toner image on the photoreceptor. Light of amounts in a plurality of steps is successively irradiated onto one point of the photoreceptor on which no toner adheres. Density data outputted by the density detecting device which correspond to the amounts of light in the respective steps are acquired. One density data is selected on a predetermined basis out of a plurality of density data acquired. Light of the amount in the step corresponding to the selected one density data (a reference amount of light) is irradiated onto a plurality of points of the photoreceptor. The density data outputted by the density detecting device at each of the points is acquired. The average value of the acquired density data corresponding to the plurality of points is found as average density data. Further, a plurality of acquired density data corresponding to the amounts of light in the plurality of steps are corrected on the basis of the average density data and the selected one density data. The amount of light for detecting a toner image density is set on the basis of the plurality of density data corrected.