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dc.contributor.authorTrillo Yáñez, María Cristina 
dc.contributor.authorFernández Doval, Ángel Manuel 
dc.date.accessioned2016-07-07T08:12:04Z
dc.date.available2016-07-07T08:12:04Z
dc.date.issued2006-08-07
dc.identifier.urihttp://hdl.handle.net/11093/360
dc.description.abstractThe measurement of ultrasonic surface acoustic waves of nanometric amplitude by TV holography (TVH) was demonstrated some years ago. The spatial periodicity of the wavefield across the optical phase difference maps was exploited to yield the mechanical amplitude and phase of the propagating wave. Now we present a refinement of the technique where we also profit from the temporal periodicity, at each point of the surface, of the displacement induced by the wave. We record a series of sets of primary correlograms,which are processed to yield optical phase-difference maps. We change slightly the delay between the excitation of the wave and the measurement from one recording to the next, so that the position of the wavefield on the resultant images is shifted accordingly. Every point on the surface, which oscillates at the frequency of the wave, is thus recorded at several instants of its oscillation cycle in consecutive optical phase difference maps of the sequence. We have then spatial periodicity at a given instant across each image and temporal periodicity at a given point on the surface across the series of images. This feature is exploited to calculate a three-dimensional Fourier transform of the data. As we employ narrowband ultrasonic waves, the spatial content of the spectrum is contained in a small region of the spatial frequency plane and within a thin slice of temporal frequencies, and can be easily filtered and inverse Fourier transformed to obtain the mechanical amplitude and phase of the wave. This method intends to extend the detection capability of the TVH technique to ultrasonic waves of lower amplitude. Keywords: spatiotemporal Fourier transform, surface acoustic waves, pulsed TV holographyspa
dc.description.sponsorshipMinisterio de Educación y Ciencia y Comisión Europea (FEDER) | Ref. DPI2005-09203-C03-01spa
dc.description.sponsorshipSecretaría Xeral de Investigación e Desenvolvemento, Xunta de Galicia | Ref. PGIDIT03PXIC30301PNspa
dc.language.isoengspa
dc.titleSpatiotemporal Fourier transform method for the measurement of narrowband ultrasonic surface acoustic waves with TV holographyspa
dc.typeconferenceObjectspa
dc.rights.accessRightsopenAccessspa
dc.identifier.doi10.1117/12.695290
dc.identifier.editorhttp://proceedings.spiedigitallibrary.org/proceeding.aspx?doi=10.1117/12.695290spa
dc.publisher.departamentoFísica aplicadaspa
dc.conferenceObject.typeComunicación extensa internacionalspa
dc.identifier.conferenceObjectSpeckle06: Speckles, From Grains to Flowers, Nîmes, Francia, 13-15 septiembre 2006spa
dc.publisher.grupoinvestigacionGrupo de Metroloxía Ópticaspa
dc.subject.unesco3311.11 Instrumentos Opticosspa
dc.subject.unesco2209.07 Holografíaspa
dc.subject.unesco2201.09 Ultrasonidosspa
dc.date.updated2016-07-06T14:13:22Z
dc.computerCitationpub_title=Spatiotemporal Fourier transform method for the measurement of narrowband ultrasonic surface acoustic waves with TV holography|volume=undefined|journal_number=|start_pag=63410M|end_pag=|congress_title=Speckle06: Speckles, From Grains to Flowers|start_date=13/9/2006|end_date=15/9/2006spa


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