Patent ID: 8111277

Claim:
An image forming apparatus comprising: a lower housing including: a plurality of photosensitive members, and a main substrate; an upper housing including: a plurality of exposure units, an exposure control substrate which is configured to control light emission of the plurality of exposure units; and a plurality of first cables which include a plurality of signal lines and electrically couple the exposure control substrate and the plurality of exposure units, a second cable which includes a plurality of signal lines and electrically couples the exposure control substrate and the main substrate; and a hinge which rotatably couples one end of the upper housing to the lower housing, wherein the first cables and the second cable are different in terms of a data transfer rate per at least one signal line and a protocol used in the data transfer, wherein the exposure control substrate is provided to the upper housing so that a centroid of the upper housing is positioned between an opposed end to the one end and a center between the end and the opposed end.