Alignment pattern detecting sensor, method of determining acceptance width of the alignment pattern detecting sensor, method of forming alignment pattern, and image forming apparatus

摘要

An image forming apparatus includes an alignment pattern and an alignment pattern detector that detects the alignment pattern. The alignment pattern is formed in such a manner that a line image of a reference color and a line image of a color other than the reference color are superposed on each other with a predetermined shift amount. An acceptance width of the alignment pattern detector is determined so that the acceptance width satisfies a relation with a writing density of the image forming apparatus and a line width of the alignment pattern, as follows: [acceptance width]>[line width]/(5.0627x[writing density (dpi)]^-0.5331).