Patent ID: 7604311

Claim:
A droplet ejection device that includes at least one printing head module in which a plurality of nozzles are arranged, and ejects ink from the printing head module to a recording medium, comprising: a latch circuit configured to acquire for each of a plurality of resolution sections a discharge data that defines a resolution in a transport direction of the recording medium to set discharge data elements for respective ones of the plurality of nozzles with respect to each of the plurality of resolution sections; an output enable signal generating unit configured to output an output enable signal periodically at intervals of a period differing from an integral multiple of a period between two of the plurality of resolution sections; a drive waveform applying unit configured to apply a drive waveform to a common electrode line of respective piezoelectric elements of the plurality of nozzles in synchronization with the output enable signal from the output enable signal generating unit, the drive waveform having a time to discharge each piezoelectric element gradually; and a switching circuit configured to turn on or off a switch based on results of ANDing the output enable signal from the output enable signal generating unit and the discharge data from the latch circuit to cause an individual electrode of each of the piezoelectric elements of the plurality of nozzles to be grounded, wherein the period of the output enable signal from the output enable signal generating unit is controlled to adjust an amount of the ink ejected.