Abstract: In the embodiments described in the specification, an ink jet head has an orifice filter disposed between a pressure chamber and an orifice to trap contaminant particles having a size likely to block the orifice, while permitting smaller particles to pass through the filter, thereby preventing blocking of the orifice while avoiding substantial pressure drop in the pulses producing ejection of drops from the orifice. In addition, a separate filter having a substantially smaller pore size is incorporated in a reservoir from which ink is supplied to the pressure chamber, thereby filtering out small particles which might accumulate to produce orifice-blocking particles.