Patent ID: 6539199
Filing Date: 2003-03-25
Classification: G03G

Abstract:
An image forming apparatus comprising:a sheet feeding unit provided with a feeding path, on which a cut sheet serving as an image forming medium having a predetermined size is fed; a sheet edge sensor having sensor elements separately arranged at portions, at which the edge of the cut sheet serving as the image forming medium having the predetermined size can be detected, along a direction perpendicular to the feeding direction of the cut sheet serving as the image forming medium on the feeding path in the sheet feeding unit; an image forming unit for forming a predetermined image on the cut sheet serving as the image forming medium to be fed by the sheet feeding unit; and an image formation correcting unit for correcting image formation according to lateral misalignment of the cut sheet serving as the image forming medium based on a detection result transmitted from the sheet edge sensor when a predetermined image is formed on the cut sheet serving as the image forming medium by the image forming unit, wherein when the presence of the sheet is detected based on the detection result transmitted from the sheet edge sensor, the image formation correcting unit adjusts a threshold as a judgment criterion of the presence of the sheet before actual detection of the sheet by the sheet edge sensor, and when the presence of the sheet is detected based on the detection result transmitted from the sheet edge sensor, the image formation correcting unit previously designates a color of the sheet, and then, resets the threshold as the judgment criterion of the presence of the sheet in accordance with the designated color.