Patent ID: 6547367
Filing Date: 2003-04-15
Classification: B41J

Abstract:
An ink jet printing apparatus for carrying out printing by moving an ink jet head in a scanning direction relative to a printing medium, said ink jet head having a plurality of ejection openings arranged therein for ejecting an ink, said apparatus comprising:means for emitting a light beam in a direction which is different from an arrangement direction of the plurality of ejection openings and which traverses a trace of the ink ejection through the ejection openings; means for receiving the emitted light beam; means for controlling said light beam emitting means to emit the light beam and for controlling said ink jet head to eject ink through the plurality of ejection openings in accordance with predetermined data, while said ink jet head is being relatively moved in the scanning direction between said light beam emitting means and said light beam receiving means; means for detecting ink ejection states from the plurality of ejection openings based on light beam receiving states at said light beam receiving means; and means for judging adhesion of ink to a face of said ink jet head on which the ejection openings are formed, based on the light beam receiving state at said light beam receiving means.