Test Pattern and Drop Tracing for Nozzle Healthy Diagnostic

Abstract

The Rayleigh instability dominates the behavior during the ink drop from jetting to forming. This paper developed a drop tracing methodology for observation the printing quality, identified the drop tail and its break-off period, satellite drop creation, drop volume variation, and jetting speed. After standard recovery cleaning process (spitting, suction, wiping, priming, etc.), the drop landing presentation and its remedy were characterized by a group of test patterns, and furthermore, to be analyzed the failure mode of the nozzles. The measurement method integrated the test pattern design, analysis algorithm and stroboscope scheme, it could automatically trace the historical changes of nozzles and the operation deterioration early warning is possible. Compare with some traditional inspection methods, like off-line auto optical inspection, high speed image capture, continuous tape-rolling dot analysis etc., this method can real-time operate and detect nozzle failure, help the operator revise processing procedure on-line.