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Maria, M. (author), Anisimov, A. (author), Stols-Witlox, Maartje (author), Groves, R.M. (author)
In this study we investigate the possibility of spectra stitching in the context of Spectral Domain - Optical Coherence Tomography (SD-OCT). The aim is to reach a high axial resolution while keeping sampling issues to a low level (slow decay in depth) but still operating with the fastest camera line rate available. The paper focuses mainly on...
conference paper 2020
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Ouyang, B. (author), Li, Yanlu (author), Kruidhof, Marten (author), Horsten, R.C. (author), Baets, Roel (author), van Dongen, K.W.A. (author), Caro, J. (author)
We report a highly sensitive ultrasound sensor based on an integrated photonics silicon Mach-Zehnder interferometer (MZI). One arm of the MZI is located on a thin membrane, acting as the sensing part of the device. Ultrasound waves excite the membrane's vibrational mode, thus inducing modulation of the MZI transmission. The measured sensor...
conference paper 2020
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Sun, S. (author), Kooij, B.J. (author), Yarovoy, Alexander (author)
In this paper, the generalized multiple measurement vectors (GMMV) linear inversion method is applied to the reconstruction of the 3-D Fresnel data, provided by the Institue Fresnel (Marseille, France). The results show that the GMMV-based method can obtain good resolution along the x- and y- axes, while poor resolution along the z-axis,...
conference paper 2019
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Verstraete, H.R.G.W. (author), Almasian, M. (author), Pozzi, P. (author), Bilderbeek, R (author), Kalkman, J. (author), Faber, DJ (author), Verhaegen, M.H.G. (author)
In this manuscript, we present a lens setup for large defocus and astigmatism correction. A deformable defocus lens and two rotational cylindrical lenses are used to control the defocus and astigmatism. The setup is calibrated using a simple model that allows the calculation of the lens inputs so that a desired defocus and astigmatism are...
conference paper 2016
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van Neer, P.L.M.J. (author), Vos, H.J. (author), Volker, AWF (author)
It is critical to use a proper spatial sampling, otherwise images suffer from grating lobes. However, the cost of a medical ultrasound scanner is strongly related to the channel count of the receive electronics. This has led to channel reduction using multiplexing or in-probe pre-beamforming methods at the cost of image quality or frame rate....
conference paper 2017
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van Berkel, S.L. (author), Malotaux, E.S. (author), Cavallo, D. (author), Spirito, M. (author), Neto, A. (author), Llombart, Nuria (author)
The design and performance analysis are presented for a passive uncooled radiometer pixel suitable for integration in 28 nm CMOS technology. In the configuration a single wideband antenna, operating from 200 GHz to 600 GHz, is connected to a pn-junction diode. Including the antenna-detector impedance mismatch, the detector shows an average NEP...
conference paper 2017
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Ramirez, Ana B (author), van Dongen, K.W.A. (author)
The design of ultrasound scanning systems for applications such as breast cancer detection is a challenging task, especially when the number of sources and receivers increases and they become spread over a large surface. In order to determine the number of transducers and above all their position, several approaches could be followed. A simple...
conference paper 2016
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Chen, C. (author), Chen, Z. (author), Chang, Z.Y. (author), Pertijs, M.A.P. (author)
This paper presents a power- and area-efficient 9-channel LNA array for piezoelectric ultrasound transducers to enable real-time 3D imaging with miniature endoscopic and catheter-based probes. In view of the relatively low impedance of piezoelectric transducers, the LNA is implemented as a capacitive feedback voltage amplifier, rather than a...
conference paper 2015
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van Rooij, J. (author)
Optical imaging is the imaging of objects with visible light. It is a tool often used for diagnostic purposes, such as in biomedical and material sciences. Digital holography is an optical imaging technique that captures and images the amplitude as well as the phase (the complex amplitude) of the lightwave. An advantage is that the complex...
doctoral thesis 2020
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Holicki, M.E. (author)
In acoustic exploration and monitoring imaging plays a critical role in uncovering structure and minute changes therein. It is, however, often hampered by unfulfilled assumptions. One such assumption is that estimated incident and reflected wavefields at a reflector travel in opposite directions with respect to the reflector surface-normal...
doctoral thesis 2020
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Zhang, W. (author)
Multimodal imaging techniques are emerging in medical diagnosis. The synergistic combination of imaging techniques, such as MRI and PET/SPECT, is highly useful to strengthen each of the individual imaging modalities while reducing any of their disadvantages. In recent years, the progress of technical integration of imaging scanners has led to a...
doctoral thesis 2016
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Mouri Sardarabadi, A. (author)
The search for the answer to one of the most fundamental scientific questions, “How was the universe formed?”, requires us to study very weak radio signals from the early universe. In the last eighty years, radio astronomers have been able to use radio frequency observations for significant discoveries such as quasars, super massive Black Holes...
doctoral thesis 2016
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Picioreanu, C. (author), Blauert, Florian (author), Horn, Harald (author), Wagner, Michael (author)
The advantage of using non-invasive imaging such as optical coherence tomography (OCT) to asses material properties from deformed biofilm geometries can be compromised by the assumptions made on fluid forces acting on the biofilm. This study developed a method for the determination of elastic properties of biofilms by modelling the biofilm...
journal article 2018
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M. A. Matias, Mayara (author), da C. Pestana, Reynam (author), van der Neut, J.R. (author)
Obtaining an accurate image of the subsurface still remains a great challenge for the seismic method. Migration algorithms aim mainly on positioning seismic events in complex geological contexts. Multiple reflections are typically not accounted for in this process, which can lead to the emergence of artefacts. In Marchenko imaging, we...
journal article 2018
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Gielis, W. P. (author), Weinans, H.H. (author), Welsing, P. M.J. (author), van Spil, W. E. (author), Agricola, R. (author), Cootes, T. F. (author), de Jong, P. A. (author), Lindner, C. (author)
Objective: To design an automated workflow for hip radiographs focused on joint shape and tests its prognostic value for future hip osteoarthritis. Design: We used baseline and 8-year follow-up data from 1,002 participants of the CHECK-study. The primary outcome was definite radiographic hip osteoarthritis (rHOA) (Kellgren–Lawrence grade ≥2...
journal article 2020
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Vinke, Elisabeth J. (author), Huizinga, W. (author), Bergtholdt, Martin (author), Adams, Hieab H. (author), Steketee, Rebecca M.E. (author), Papma, Janne M. (author), De Jong, Frank Jan (author), Niessen, W.J. (author), Ikram, M. Arfan (author)
Brain imaging data are increasingly made publicly accessible, and volumetric imaging measures derived from population-based cohorts may serve as normative data for individual patient diagnostic assessment. Yet, these normative cohorts are usually not a perfect reflection of a patient's base population, nor are imaging parameters such as field...
journal article 2019
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Tan, M. (author), Chen, C. (author), Chen, Z. (author), Janjic, Jovana (author), Daeichin, V. (author), Chang, Z.Y. (author), Noothout, E.C. (author), van Soest, G. (author), Verweij, M.D. (author), de Jong, N. (author), Pertijs, M.A.P. (author)
This paper presents an area- and power-efficient application-specified integrated circuit (ASIC) for 3-D forward-looking intravascular ultrasound imaging. The ASIC is intended to be mounted at the tip of a catheter, and has a circular active area with a diameter of 1.5 mm on the top of which a 2-D array of piezoelectric transducer elements is...
journal article 2018
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Sun, Yimin (author), Kim, Young Seo (author), Qu, S. (author), Verschuur, D.J. (author)
Joint migration inversion is a recently proposed technology, accommodating velocity model building and seismic migration in one integrated process. Different from the widely accepted full waveform inversion technology, it uses imaging parameters, i.e. velocities and reflectivities of the subsurface, to parameterize its solution space. The...
journal article 2020
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Sun, Yimin (author), Verschuur, D.J. (author), Luo, Yi (author)
Near-surface problem is a common challenge faced by land seismic data processing, where often, due to near-surface anomalies, events of interest are obscured. One method to handle this challenge is near-surface layer replacement, which is a wavefield reconstruction process based on downward wavefield extrapolation with the near-surface...
journal article 2017
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Wei, Wei (author), Blacquière, G. (author)
Focal beam analysis has built a bridge between the acquisition parameters on the surface and the image quality of underground targets. However, as a practical matter, it is still difficult to answer how to choose a proper acquisition geometry according to the complexity of medium, especially considering the contradictory effects of multiple...
journal article 2021
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