Patent ID: 7449708

Claim:
A paper detection apparatus for detecting a size of a sheet of paper transferred along a paper transfer path, the paper detection apparatus comprising: a light source; an optical sensor; a feeding method detection sensor located close to a reference edge of a paper transfer path for detecting whether the sheet of paper is transferred in a side feeding method or a center feeding method, according to whether the paper transferred along the paper transfer path is detected; a plurality of light emitting optical fibers located at a first side of the paper transfer path for receiving light radiated by the light source and emitting the received light to a plurality of positions in a widthwise direction of the paper; a plurality of light receiving optical fibers located at a second side of the paper transfer path for guiding the light emitted by the light emitting optical fibers toward the optical sensor; and a determination unit for detecting the size of the paper based on the amount of light detected by the optical sensor.