Motion measurement of acoustically levitated object
US5203209A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 1991 |
| Grant date | Apr 20, 1993 |
| Priority date | — |
| Expiry date | Feb 25, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01H17/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system is described for determining motion of an object that is acoustically positioned in a standing wave field in a chamber. Sonic energy in the chamber is sensed, and variation in the amplitude of the sonic energy is detected, which is caused by linear motion, rotational motion, or drop shape oscillation of the object. Apparatus for detecting object motion can include a microphone (24) coupled to the chamber and a low pass filter (40) connected to the output of the microphone, which passes only frequencies below the frequency of sound produced by a transducer (18) that maintains the acoustic standing wave field. Knowledge about object motion can be useful by itself, can be useful to determine surface tension, viscosity, and other information about the object, and can be useful to determine the pressure and other characteristics of the acoustic field.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.