Patent ID: 8807712

Claim:
An inkjet printer head comprising: a semiconductor substrate; a vibration diaphragm provided on the semiconductor substrate and configured to vibrate in an opposing direction in which the vibration diaphragm is opposed to the semiconductor substrate; a piezoelectric element provided on the vibration diaphragm; a pressure chamber, provided on a side of the vibration diaphragm adjacent to the semiconductor substrate, and facing the vibration diaphragm, the pressure chamber being configured to be filled with an ink; and a nozzle extending through the vibration diaphragm and communicating with the pressure chamber via a straight ink path for ejecting the ink supplied from the pressure chamber, the straight ink path having a first end coupled to the pressure chamber and a second end coupled to the nozzle; wherein the nozzle includes a first surface defining a first region on a side of the first end and a second surface defining a second region on a side of the second end, the second region being nearer to an outside of the inkjet printer head than the first region; wherein the first surface is a curved surface and inclines with respect to the opposing direction so as to widen the first region gradually toward the pressure chamber and the second surface extends straight along the opposing direction; and wherein the first surface extends to a vertical direction and gradually curves to a horizontal direction so that a hollow space defined by the first surface curves and the surface of the hollow space is rounded.