(i9) United States
(12) Patent Application Publication
Ellson et al.
(54) ACOUSTIC ASSESSMENT OF
CHARACTERISTICS OF A FLUID RELEVANT
TO ACOUSTIC EJECTION
(75) Inventors: Richard N. Ellson, Palo Alto, CA
(US); Mitchell W. Mutz, Palo Alto,
CA (US); Shehrzad Ahmed
Qureshi, Palo Alto, CA (US);
Richard G. Stearns, Felton, CA
MINTZ, LEVIN, COHN, FERRIS, GLOVSKY
AND POPEO, P.C
1400 PAGE MILL ROAD
PALO ALTO, CA 94304-1124
(73) Assignee: Labcyte Inc., Sunnyvale, CA (US)
(21) Appl.No.: 12/079,173
(22) Filed: Mar. 24, 2008
Related U.S. Application Data
(60) Division of application No. 11/048,285, filed on Jan. 31, 2005, now Pat. No. 7,354,141, which is a continuation-in-part of application No. 10/310,638, filed on
Dec. 4, 2002, now Pat. No. 6,938,995, which is a continuation-in-part of application No. 10/010,972, filed on Dec. 4,2001, now abandoned, said application No. 11/048,285 is a continuation-in-part of application No. 10/956,616, filed on Oct. 1, 2004.
(51) Int. CI.
G01N 29/024 (2006.01)
(52) U.S. CI 73/64.53
Methods are provided for analyzing characteristics of fluids in the context of an acoustic ejection system. Such a system has a controller, an acoustic radiation generator, and a coupling medium coupling the radiation to a reservoir holding fluid. The methods can use acoustic radiation to both perturb a surface of the fluid in the reservoir and analyze the effect of the perturbation. The methods may use information about prior fluids. The methods of the invention can determine physical characteristics such as speed of sound and viscosity. The methods also include ways to determine a level of acoustic energy suitable to eject a droplet. Preferably the methods are executed automatically under control of programming of a controller of an acoustic ejection system.