Patent ID: 7427118

Claim:
A method for detecting intermittent, weak or missing jets of a printer having a row of nozzles, the method comprising: printing a test pattern in its entirety, the test pattern having an array of dashes produced by the row of nozzles; sensing the test pattern using a sensor; obtaining a first response profile based on a first cross section of the sensed test pattern; obtaining a first metric for the first response profile; obtaining a difference between the first metric and a reference; and determining a nozzle that produces intermittent, weak or missing jets based on the difference by determining whether the difference is greater than a threshold, wherein if the difference is greater than the threshold, the method further comprising: printing a confirmation pattern that is separate from the test pattern, the confirmation pattern being printed to be identical to a part of the printed and sensed test pattern; and confirming the intermittent, weak or missing jets over the confirmation pattern.