Patent ID: RE38941

Claim:
An ink droplet ejecting method, wherein a jet pulse signal is applied to an actuator, for changing the volume of an ink chamber filled with ink, to generate a pressure wave within the ink chamber, thereby applying pressure to the ink and allowing a droplet of the ink to be ejected from a nozzle comprising the steps of: applying said jet pulse signal to said actuator in accordance with a one-dot printing instruction, said jet pulse signal having a pulse width which allows the volume of said ink chamber to increase upon application of a leading edge of said jet pulse signal to said actuator, thereby causing a pressure wave to be generated within the ink chamber, and which, after the lapse of time T required for an approximately one-way propagation of the pressure wave through the ink chamber or after the lapse of an odd-multiple time of said time T, allows the volume of the ink chamber to decrease from the increased state to a normal state; and applying an additional pulse signal to said actuator in accordance with the one-dot printing instructions, said additional pulse signal having a pulse width of approximately 0.2T to 0.6T relative to said jet pulse signal and a time difference between a trailing edge of said jet pulse signal and a leading edge of said additional pulse signal being 0.3T to 0.7T.