Abstract
A method for producing a stream of uniform-sized liquid droplets and individual droplets is discussed in detail. The method is based on the principle that a cylinder of liquid (jet) is dynamically unstable under the action of surface tension. When a capillary wave of a prescribed wavelength is applied to the jet, the jet will disintegrate into a stream of uniform-sized droplets. Since the droplet size depends on the capillary tube through which the liquid flows, the size can be easily varied. A piezoelectric transducer is used to produce the capillary wave on the jet. The apparatus discussed will produce droplets in a range between 25 and 350 μm in radius. The method is unique in that the droplet size can be precisely controlled and individual droplets can be produced at will.