Patent ID: 7614711

Claim:
A liquid droplet ejection apparatus comprising: a nozzle from which a liquid droplet is ejected; a print controller for driving the liquid droplet ejection apparatus at an ejection frequency of f; a pressure chamber filled with liquid to which a pressure is applied in order to eject the liquid in a form of the liquid droplet from the nozzle; and a supply port which supplies the liquid to the pressure chamber, wherein inertance Mn of the nozzle, resistance Rn of the nozzle, compliance Cn of a nozzle section due to surface tension, inertance Ms of the supply port, and resistance Rs of the supply port satisfy the following two formulas: 1 Mn + Ms ⁢ Mn + Ms Cn - ( Rn + Rs ) 2 4 > π ⁢ ⁢ f - Rn + Rs 2 ⁢ ( Mn + Ms ) × 1 f < log ⁢ ⁢ 0.01 .