Method and apparatus for determining drop volume from a drop ejection device

摘要

A device for determining drop volume for a drop ejection device is disclosed. The drop ejection device has a drop ejector and a reference drop ejector that exhibits less drop volume variation than the drop ejector. The drop ejection device includes a sensor responsive to impinging drops for producing a signal proportional to drop volume. The sensor is responsive to drops from the drop ejector to produce an electrical signal. The sensor is responsive to drops from the reference drop ejector to produce a reference electrical signal. Also included is a processing device responsive to the electrical signal and reference electrical signal for determining drop volume of the drop ejector relative to drop volume of the reference drop ejector.