Patent ID: 6851778
Filing Date: 2005-02-08
Classification: B41J

Abstract:
1. A method for driving a droplet ejecting head including: a nozzle having a straight portion formed into a substantially straight shape with a small taper angle; a pressure generating chamber communicating with the nozzle; and an electromechanical transducer, the method comprising the steps of: applying a driving voltage to the electromechanical transducer; deforming the electromechanical transducer; producing pressure change in the pressure generating chamber filled with liquid; and ejecting a droplet from the nozzle, wherein a voltage waveform of the driving voltage includes: a first voltage change process for expanding volume of the pressure generating chamber to retract a meniscus in the nozzle toward the pressure generating chamber; and a second voltage change process for compressing the volume of the pressure generating chamber to eject the droplet; and wherein voltage change quantity and voltage change time of the first voltage change process are set so that retraction quantity D of the meniscus at a time when the second voltage change process is applied satisfies:  where l