Acousto-optical transducer
US4188096A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 2, 1976 |
| Grant date | Feb 12, 1980 |
| Priority date | — |
| Expiry date | Apr 2, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01H9/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An acousto-optical transducer which includes a pair of mirrors of high reflectivity arranged in parallel to form an etalon. A laser beam enters the etalon at a small angle of incidence through a window and after suffering many reflections at the etalon mirrors exits at the second window. The reflected beam carries the information imposed by an acoustic pressure wave which affects the position of the etalon mirrors. The reflected laser beam of changed frequency due to the doppler shift caused by the motion of the etalon mirrors relative to the source of the incident laser beam is then used to beat with a light of a fixed frequency by using the heterodyne technique. Alternatively, an additional mirror is used which is generally perpendicular to the etalon mirrors and facilitates the reflections at the etalon mirrors for the ultimately reflected beam.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.