Ultrasonic vibration detection using frequency matching
US6700666B2 · kind B2 · utility
3Cited by
7References
33Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 24, 2002 |
| Grant date | Mar 2, 2004 |
| Priority date | — |
| Expiry date | Apr 24, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/0427
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In order to probe an object in motion subject to surface displacement, for example, caused by ultrasonic wave propagation, a laser beam is split into a first portion and a second portion. The first is scatted off the object to generate a signal beam. The frequency shift produced in the signal beam due to motion of the object is measured, and this is used to adjust the frequency of one or both portions of the laser beam so that both beams have substantially the same frequency. The surface displacements are measured by comparing the second portion of the laser beam and the signal beam after frequency adjustment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.