Digital off-axis heterodyne holographic interferometry for detecting vibration amplitude
US9733064B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 15, 2013 |
| Grant date | Aug 15, 2017 |
| Priority date | — |
| Expiry date | Jan 24, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03H2227/03
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The invention relates to a digital holography method for detecting the vibration amplitude of an object (15) having a vibration frequency ω, comprising: generating object illumination waves (Wt) and reference waves (WLO); acquiring interferograms between the reference wave (WLO) and a signal wave (Ws) by means of a bandwidth ω s detector (19), the reference wave comprising two components ELO1, ELO1 of frequencies ω1, ω2 that are respectively staggered in relation to the laser frequency ωL by a quantity δ1=γ1ωs and δ2=qω+γ2ωs, where q is an integer and −0.5≦γ1, γ2≦0.5; and calculating the vibration amplitude of the object from the optical beats spectrum deduced from the complex amplitude of an interferogram.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.