Searched for: subject%3A%22Interferometry%22
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Martins, Joana E. (author), Hooper, Andy (author), Ruigrok, E.N. (author), Draganov, D.S. (author), Hanssen, R.F. (author), White, Robert (author), Soosalu, Heidi (author)
Torfajökull is the largest silicic volcanic centre in Iceland lying at the intersection of the rift zone (MidAtlantic Ridge) and the transform zone that connects to Reykjanes peninsula. It erupts infrequently,with only two eruptions in the last 1200 years, the latest of which was over 5 centuries ago. Yet, itsactive tectonic setting, persistent...
abstract 2014
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Draganov, D.S. (author), Ghose, R. (author), Heller, H.K.J. (author)
Purpose: Time-lapse seismic monitoring constitutes the foundation for most monitoring programmes involving CO2 storage. When using time-lapse seismics, two major sources of uncertainty in the estimation of changes in the reservoir properties, like saturation and pressure, are the non-repeatability of the source positions and the difficulty to...
abstract 2016
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Shirmohammadi, F. (author), Draganov, D.S. (author)
High-resolution seismic reflections are essential for imaging and monitoring applications using data-driven methods such as seismic interferometry (SI) and Marchenko redatuming. For seismic land surveys using sources and receivers at the surface, the surface waves are the dominant noises that mask the reflections. We use SI to suppress surface...
abstract 2023
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Nijholt, J.L.M. (author)
This book describes the theoretical design of a three camera Michelson interferometer set-up for quantitative refractive index measuerments. Although a two camera system is easier to align and less expensive, a three camera interferometer is preferred because the expected measuring accuracy is much better. Here analytical expressions are found...
book 1998
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Konijnenberg, A.P. (author), Adam, A.J.L. (author), Urbach, Paul (author)
This book treats optics at the level of students in the later stage of their bachelor or the beginning of their master. It is assumed that the student is familiar with Maxwell’s equations. Although the book takes account of the fact that optics is part of electromagnetism, special emphasis is put on the usefulness of approximate models of optics...
book 2021
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Konijnenberg, A.P. (author), Adam, A.J.L. (author), Urbach, Paul (author)
This book treats optics at the level of students in the later stage of their bachelor or the beginning of their master. It is assumed that the student is familiar with Maxwell’s equations. Although the book takes account of the fact that optics is part of electromagnetism, special emphasis is put on the usefulness of approximate models of optics...
book 2024
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Wapenaar, C.P.A. (author), Snieder, Roel (author), Ridder, Sjoerd de (author), Slob, E.C. (author)
Marchenko redatuming, imaging, monitoring and multiple elimination methods are based on Green’s function representations, with the underlying assumption that the wave field in the subsurface can be decomposed into downgoing and upgoing waves and that evanescent waves can be neglected. In this paper we show that up/down decomposition in the...
book chapter 2021
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Kiraz, Mert S. R. (author), Snieder, Roel (author), Wapenaar, C.P.A. (author)
Marchenko algorithms retrieve the Green’s function for arbitrary subsurface locations, and the retrieved Green’s function includes the primary and multiple reflected waves. The Marchenko algorithms require the estimate of the direct arrivals and the reflected waves; however, most previous Marchenko algorithms also require the up/down components...
book chapter 2021
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Inamdar, A.S. (author), Gromala, Przemyslaw Jakub (author), Prisacaru, Alexandru (author), Kabakchiev, Alexander (author), Yang, Yu Hsiang (author), Han, Bongtae (author)
Epoxy molding compound (EMC) is widely used for encapsulating automotive electronics. Among all of the components of an electronic package, EMC is most exposed to the atmosphere, and thus undergoes aging. During high-temperature operation, EMC is oxidized, which alters its mechanical properties, and thus can affect the reliability of electronic...
book chapter 2022
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Somers, P.A.A.M. (author), Bhattacharya, N. (author)
Phase stepping algorithms are mostly based on three or more interferograms that can either be acquired sequentially, involving some temporal phase stepping mechanism, or in parallel. When a phase step is applied between acquisitions, object phase changes may cause phase errors when calculating phase. A new system that allows the object to change...
conference paper 2006
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Somers, P.A.A.M. (author), Bhattacharya, N. (author)
A polarization phase stepping method is presented based on the use of a polarization plane rotator that establishes a relative phase shift between two counter-rotating circularly polarized beams. The phase step can be made relatively accurate, since it just depends on the accuracy with which the rotator is manufactured, and not on its...
conference paper 2005
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Spronck, J. (author), Pereira, S.F. (author), Braat, J.J.M. (author)
We discuss the previously-reported measurements of a three-beam nulling interferometer without achromatic phase-shifters, using delay lines only. The theoretical rejection ratio of a few thousand has not been achieved experimentally. In order to explain the obtained results, some direct spectral and polarization measurements have been performed....
conference paper 2006
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Soloviev, O. (author), Vdovin, G. (author)
We propose an algorithm for phase retrieval from three interferograms which differ only by an arbitrary unknown tilt terms in the phase. The method is illustrated by examples.
conference paper 2005
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Soloviev, O. (author), Vdovin, G. (author)
This article presents a prototype of a CMOS phase sensor for high accuracy (1 Angstrom) heterodyne interferometry. Switched integrators realization of a lock-in pixel for 4-bucket phase detection algorithm is described and illustrated by experimental results. Factors that limit the accuracy of this implementation and possible ways for its...
conference paper 2005
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Krieg, M.L. (author), Braat, J.J.M. (author)
This paper will illustrate several approaches to retrieving the shape of aspherical reflective surfaces as used in EUV Lithography, from measurements from a previously reported angstrom-accuracy interferometer. First, the working principles of the interferometer will be reviewed, and typical measurement data expected from the instrument will be...
conference paper 2004
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Spronck, J. (author), Pereira, S.F. (author), Braat, J.J.M. (author)
We present a new type of nulling interferometer that makes use of polarization properties to have on-axis destructive interference. The proposed design, which only involves commercial components and no achromatic device, is also suitable for internal modulation. This type of interferometer should enable a high rejection ratio in a theoretically...
conference paper 2006
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Slob, E.C. (author), Hunziker, J.W. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)
conference paper 2014
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Van Brug, H. (author), Oostdijck, B. (author), Snijders, B. (author), Van der Avoort, C. (author), Gori, P.M. (author)
The Delft Testbed Interferometer (DTI) will be presented. The basics of homothetic mapping will be explained together with the method of fulfilling the requirements as chosen in the DTI setup. The optical layout incorporates a novel tracking concept enabling the use of homothetic mapping in real telescope systems for observations on the sky. The...
conference paper 2004
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Van der Avoort, C. (author), Mieremet, A. (author), Pereira, S. (author), Braat, J. (author)
We present results of experiments obtained using a new nulling technique that enables deep nulling without the use of achromatic phase shifters. The experimental set-up consists of a three-beam interferometer that should provide a nulling depth of several thousands over a wavelength range of 500 to 650 nm. The intended depth of null was not...
conference paper 2004
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Van der Avoort, C. (author), Van Brug, H. (author), Den Herder, J.W. (author), d'Arcio, L. (author), Le Poole, R. (author), Braat, J. (author)
Homothetic mapping is an aperture synthesis technique that allows interferometric imaging over a wide fieldof-view. A laboratory experiment was set up to demonstrate the feasibility of this technique. Here, we present the first static experiments on homothetic mapping that have been done on the Delft Testbed for Interferometry (DTI). Before a...
conference paper 2004
Searched for: subject%3A%22Interferometry%22
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