Patent ID: 7715708
Filing Date: 2010-05-11
Classification: B41J

Abstract:
1. A method of detecting a position of printing performed by a printing apparatus, the method comprising: locating an optical sensor comprising a photo emitter operable to emit light and a photo receiver operable to receive light and output a first signal in accordance with an amount of the received light at a position above a marker provided on a tray; emitting light from the photo emitter to irradiate the marker; receiving light reflected from the marker with the photo receiver; determining a threshold value based on a first value of the first signal outputted from the photo receiver when the marker is irradiated; changing a relative position between the optical sensor and the tray, while emitting light from the photo emitter: comparing the first signal outputted from the photo receiver with the threshold value while the relative position is changed; and determining a position at which the printing begins based on the comparison between the first signal and the threshold value.