Patent ID: 8249477

Claim:
A method of detecting a position of a toner pattern in an image forming apparatus including a light-emitting unit that includes M number of light-emitting elements aligned in a single direction intersecting a first direction, where M is equal to or larger than three, and emits a detection light such that M number of light spots fall on a supporting member that makes a surface movement in the first direction with a distance between adjacent light spots in a second direction perpendicular to the first direction on the supporting member equal to or smaller than a length of a toner pattern in the second direction and a light-receiving unit that includes N number of light-receiving elements that receive a reflected light from at least one of the supporting member and the toner pattern, where N is equal to or larger than three, and aligned opposed to the supporting member in a single direction corresponding to the light-emitting units, the method comprising: forming the toner pattern on a surface of the supporting member; emitting the detection light onto the supporting member with the light-emitting unit; receiving a reflected light reflected from at least one of the supporting member and the toner pattern with the light-receiving unit; and detecting the position of the toner pattern on the supporting member based on outputs of the light-receiving elements.