TRÖPFCHENABGABEGERÄT

Droplet deposition apparatus comprises a plurality of fluid chambers (2), each fluid ejection chamber being defined in part by at least one wall (11) actuable by an electrical signal to effect droplet ejection from that chamber. The apparatus provides means (16) for cyclically supplying electrical signals to the walls (11) for actuation thereof, means (60) for measuring, within a period between the application of successive electrical signals to the walls, a temperature dependent electrical property of a wall of a fluid chamber to provide a signal having a magnitude dependant on the temperature of fluid in the fluid chambers, and means for adjusting the magnitude of the actuating electrical signals depending on the magnitude of the temperature dependant signal.