Measuring vibrational frequency of vibratable pins
US4850225A · kind A · utility
2Cited by
5References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 31, 1988 |
| Grant date | Jul 25, 1989 |
| Priority date | — |
| Expiry date | Oct 31, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N29/2418
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Measuring vibrational frequency of a pin attached at one end by collimating two laser beams onto the pin and back scattering the beams. The back scattered frequency is modulated by doppler effect and is heterodyned with the original beam frequency to produce a signal representative of each modulating frequency. The representative signals are summed together and also subtracted from one another. The summed and subtracted signals are representative, one of the vibrational frequency of the pin and the other of the degree of focussing accuracy of each laser beam onto the pin.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.