Patent ID: 8801129

Claim:
A method for operating a jetting module comprising: providing a jetting module including a nozzle and a drop forming mechanism; providing a liquid to the jetting module under pressure sufficient to cause a liquid stream to jet from the nozzle; providing a small-drop waveform, the small drop waveform having a starting endpoint and a trailing endpoint, the small-drop waveform having a small-drop period X S equal to the time between the starting endpoint and the trailing endpoint of the small-drop waveform, the small-drop waveform including a small drop volume-control pulse, the small-drop volume-control pulse of the small-drop volume-control pulse having centroid, the centroid of the small-drop volume-control pulse being at a first defined time relative to a predefined one of the starting endpoint and the trailing endpoint of the small-drop waveform; providing a large-drop waveform, the large-drop waveform having a starting endpoint and a trailing endpoint, the large-drop waveform having a large-drop period X L , where X L =N*X S and N is an integer greater than one, the large-drop waveform including a large-drop volume-control pulse, the large-drop volume-control pulse having centroid, the large-drop waveform having a corresponding endpoint that corresponds to the predetermined endpoint of the small-drop waveform; wherein the centroid of the large-drop volume-control pulse being at a second defined time relative to the corresponding one of the starting endpoint and trailing endpoint of the large-drop waveform, the second defined time being different from the first defined time; applying to the drop forming mechanism a sequence of drop formation waveforms in which: applying a small-drop waveform after another identical small-drop waveform causes a small drop of volume Vs to be formed; applying a small-drop waveform after a large-drop waveform causes a small drop of volume Vs2 to be formed, where V S2 is not equal to V S ; applying a large-drop waveform after another identical large-drop waveform causes a large drop of volume VL to be formed, where V L ˜N*Vs; and applying a large-drop waveform after a small-drop waveform causes a large drop of volume VL2 to be formed, where V L2 is not equal to V L .