Patent ID: 8770691
Filing Date: 2014-07-08
Classification: B01J,B01L,B05B,B41J

Abstract:
1. An apparatus for acoustically ejecting a droplet of fluid from each of a plurality of reservoirs comprising: a plurality of fluid reservoirs contained in or located on a substrate; a quantity of fluid disposed in each reservoir of the plurality of fluid reservoirs; an acoustic radiation generator for generating at least one pulse of acoustic radiation; a means for successively acoustically coupling the acoustic radiation generator with each reservoir such that at least one pulse of acoustic radiation generated by the acoustic radiation generator is transmitted through the substrate and into the fluid to a site at or near the surface of the fluid in each reservoir in a manner effective to eject a droplet from each reservoir acoustically coupled to the acoustic radiation generator; and an analyzer for determining, prior to acoustically ejecting a droplet of fluid from a reservoir, the wave form of a droplet-forming pulse of acoustic radiation to be generated, wherein the analyzer is further configured to determine an amplitude for the droplet-forming pulse which is sufficient to eject a fluid droplet; wherein the analyzer is further configured to, for determining the amplitude for the droplet-forming pulse for a reservoir: wherein the processing of step (v) includes analyzing the frequency spectrum of a portion of the reflection detected in step (iv); wherein the processing of step (v) includes using a frequency domain-based algorithm to identify the difference in frequency between two minima of the frequency spectrum of the reflection detected in step (iv).