Patent ID: 6322190
Filing Date: 2001-11-27
Classification: B41J

Abstract:
An ink-jet printing apparatus for performing printing by ejecting an ink toward a printing medium by employing at least one ink-jet head on which a predetermined number of ink-jet openings are arranged, comprising:detection means including a light emitting element and a photo-sensing element, said detection means for differentiating an output therefrom in accordance with an interrupting state of a light path formed between said light emitting element and said photo-sensing element;control means for sequentially selecting, from one of the at least one ink-jet head, a group composed of a plurality of ejection openings and formed by dividing the predetermined number of ejection openings of the one ink-jet head, to cause the one ink-jet head to sequentially eject ink from all of the election openings of each selected group of ejection openings to the light path formed between said light emitting element and said photo-sensing element; andejection failure determining means for determining an ejection failure state of each selected group of ejection openings based on the output from said detection means, the output being obtained when said control means causes each selected group of ejection openings to eject the ink, wherein said ejection failure determining means determines the ejection failure state of each selected group by determining whether any ejection opening composing a selected group is in an ejection failure state.