In an apparatus for measuring an ejection velocity of a liquid droplet ejected from a nozzle orifice of a head device which is provided with a pressure chamber communicated with the nozzle orifice and an actuator which varies pressure of liquid contained in the pressure chamber, a driver generates a...http://www.google.com.tw/patents/US6897466?utm_source=gb-gplus-share專利 US6897466 - Instrument and method for measuring ejection velocity of liquid
