Patent ID: 8457509
Filing Date: 2013-06-04
Classification: G03G

Abstract:
1. An image forming apparatus that forms an image on an image carrier and transfers the image thus formed on paper to be fixed, the image forming apparatus comprising: an obtaining unit a light amount setting unit a detecting unit that detects a pattern image a controller that controls image formation on the image carrier based on a detected result by the detecting unit, wherein the detecting unit maintains the threshold at a constant value when the required light amount value does not exceed the limiting value, and reduces the threshold when the required light amount value exceeds the limiting value depending on a degree of the excess, the limiting value being an upper limit of a driving voltage of the light-emitting unit, the pattern image includes a plurality of images, having predetermined widths, varying in a plurality of colors, and which are formed at a predetermined pitch with non-color area between the plurality of images in a sub-scanning direction of the image carrier, and the obtaining unit obtains respective output values corresponding to each of the plurality of colors from each of a plurality of sensors, each sensor including one of the light-emitting unit and one of the light-receiving unit.