摘要:
A first LED that is one of a plurality of LEDs arranged in the main scanning direction is turned on, and the presence of a document on a document table glass is determined by detection of reflected light from the document using a CCD sensor, and a second LED other than the first LED in addition to the first LED among the plurality of LEDs is turned on when it is determined that a document is placed on the document table glass, and the size of the document on the document table glass is determined based on a scanning result of the CCD sensor on the reflected light from the document caused by illumination from the first and the second LEDs and a detection result of a reflective photosensor.