METHOD FOR DETECTING INK DROP IN PRINTER

摘要

PROBLEM TO BE SOLVED: To shorten the time required for testing a plurality of nozzles before executing print by repeating measurement of ink drop in the vicinity of an ink drop detector thereby decreasing the number of ink drops required to be sampled for providing a functioning ink ejection nozzle. SOLUTION: A printer head 400 including a plurality of nozzles for ejecting ink, a light emitting element 540 and a light receiving element 560 in a means for detecting a series of ink drops being ejected from the plurality of nozzles, and means 520 for measuring an output signal pulse formed depending on each detected ink drop are provided. The measuring means generates a signal indicative of the performance of the nozzle depending on a signal from the detector resulting from at least one ink drop containing ink of specified volume traversing the optical path of each nozzle. An instruction for ejecting a series of specified ink drops from the nozzles is delivered to the head and the output signal from the ink drop detecting means is measured thus determining the operational characteristics of the nozzle.