Physical quantity sensor and physical quantity measuring method
US8982336B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 10, 2010 |
| Grant date | Mar 17, 2015 |
| Priority date | — |
| Expiry date | Jul 7, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S17/58
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A physical quantity sensor includes a semiconductor laser for irradiating an object with a laser beam, and a laser driver for operating the semiconductor laser in such a way that a first oscillation period for which the oscillation wavelength increases and/or a second oscillation period for which the oscillation wavelength decreases is repetitively present. The sensor further includes a photodiode and a current-voltage conversion amplifying unit both for detecting an MHP containing an interference waveform formed by the self-coupling effect between the laser beam and the returning light beam from the object, a MHP extracting unit for measuring the period of the interference waveform contained in the output signal from the current-voltage conversion amplifying unit each time the interference waveform is inputted, and a computing unit for computing the displacement and/or the speed of the object from the measured individual period MHP extracting unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.