Acousto-optic tunable filter and method of calculating its equivalence incident angle
US5973822A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 23, 1997 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | Dec 23, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/116
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In a non-collinear type acousto-optic tunable filter, the incident angle of a source light beam L.sub.1 radiated from a light source 6 onto an acoustic medium 1 is set at an equivalence incident angle for which the wavelength .lambda..sub.i of the diffracted ordinary ray L.sub.3 and the wavelength .lambda..sub.i ' of the diffracted extraordinary ray L.sub.4 become approximately identical. Further, the diffracted ordinary ray L.sub.3 and the diffracted extraordinary ray L.sub.4 of the approximately identical wavelength are superposed, and the intensity of the superposed ray is detected. Consequently, spectrometry is performed based on the superposed diffracted ray having twice the intensity and a very sharp waveform, so that accurate spectroscopy can be made possible even if the intensity of the source light beam is low.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.