Searched for: author%3A%22Kalkman%2C+J.%22
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Cheishvili, K. (author), Rieger, B. (author), Kalkman, J. (author)
We quantify the precision and bias of dynamic light scattering optical coherence tomography (DLS-OCT) measurements of the diffusion coefficient and flow speed for first and second-order normalized autocovariance functions. For both diffusion and flow, the measurement precision and accuracy are severely limited by correlations between the...
journal article 2024
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Speets, P.N.A. (author), Kalkman, J. (author)
The complex refractive index is analyzed by measuring its scattering attenuation µ<sub>s</sub>, group index n<sub>g</sub>, and group velocity dispersion (GVD) for 100 nm diameter silica nanoparticles dispersed in water. The experiments were performed for wavelengths between 410 nm and 930 nm. The experimental results were compared with...
journal article 2024
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Cheishvili, K. (author), Besseling, Rut (author), Hermes, Michiel (author), Kalkman, J. (author)
We demonstrate wavenumber-dependent DLS-OCT measurements of collective and self-diffusion coefficients in concentrated silica suspensions across a broad q-range, utilizing a custom home-built OCT system. Depending on the sample polydispersity, either the collective or self-diffusion is measured. The measured collective-diffusion coefficient...
journal article 2024
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Shangguan, H. (author), Urbach, Paul (author), Kalkman, J. (author)
We demonstrate lensless single-shot dual-wavelength digital holography for high-speed 3D imaging in industrial inspection. Single-shot measurement is realized by combining off-axis digital holography and spatial frequency multiplexing of the two wavelengths on the detector. The system has 9.1 µm lateral resolution and a 50 µm unambiguous depth...
journal article 2024
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Cheishvili, K. (author), Kalkman, J. (author)
We show scanning dynamic light scattering optical coherence tomography (OCT) omnidirectional flow measurements. Our method improves the velocity measurement limit over conventional correlation-based or phase-resolved Doppler OCT by more than a factor of 2. Our technique is applicable without a-priori knowledge of the flow geometry as our...
conference paper 2023
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Cheishvili, K. (author), Kalkman, J. (author)
We show number fluctuations dynamic light scattering optical coherence tomography (OCT) for measuring extremely slow, sub-diffusion flows of dilute particle suspensions. Our method removes the minimum measurable velocity limitation of conventional correlation-based or phase-resolved Doppler OCT, set by flowing particles’ Brownian motion. Our...
conference paper 2023
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Speets, P.N.A. (author), Kalkman, J. (author)
The group index, n<sub>g</sub> , group velocity dispersion (GVD), and scattering attenuation coefficient, µ<sub>s</sub>, were measured for dilutions of glycerol, ethanol, and Intralipid 20% with water. Experiments were performed with a supercontinuum laser based Mach–Zehnder spectroscopic interferometry setup for wavelengths between 400 and...
journal article 2023
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de Wit, J. (author), Glentis, George Othon (author), Kalkman, J. (author)
Phase-preserving spectral estimation optical coherence tomography (SE-OCT) enables combining axial resolution improvement with computational depth of field (DOF) extension. We show that the combination of SE-OCT with interferometric synthetic aperture microscopy (ISAM) and computational adaptive optics (CAO) results in high 3D resolution over...
journal article 2023
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de Wit, J. (author), Glentis, George Othon (author), Kalkman, J. (author)
Phase sensitive optical coherence tomography (OCT) is able to measure small axial motion at the level of ten nanometer. However, when interfaces are located close to each other, the phase of one interface may influence the phase of the other interface. This spectral leakage hampers the ability to see relative motion between structures within...
conference paper 2023
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de Wit, J. (author), Glentis, George Othon (author), Kalkman, J. (author)
Phase-preserving spectral estimation optical coherence tomography (SE-OCT) enables combining axial resolution improvement with computational depth of focus (DOF) extension. We combine SE-OCT with interferometric synthetic aperture microscopy (ISAM) to obtain a high 3D resolution over a large depth range with a narrow bandwidth visible light...
conference paper 2023
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Cheishvili, K. (author), Kalkman, J. (author)
We show number fluctuations dynamic light scattering optical coherence tomography (OCT) for measuring extremely slow, sub-diffusion flows of dilute particle suspensions. Our method removes the minimum measurable velocity limitation of conventional correlation-based or phase-resolved Doppler OCT, set by flowing particles’ Brownian motion. Our...
conference paper 2023
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Cheishvili, K. (author), Kalkman, J. (author)
We have implemented number fluctuation dynamic light scattering optical coherence tomography (OCT) for measuring extremely slow, sub-diffusion flows of dilute particle suspensions using the second-order autocovariance function. Our method has a lower minimum measurable velocity than conventional correlation-based OCT or phase-resolved Doppler...
journal article 2023
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Sewalt, E.J.G. (author), Kalkman, J. (author), van Ommen, J.R. (author), Meesters, G.M.H. (author), van Steijn, V. (author)
Properties of powders produced from drying solute-containing droplets arise from the dynamic redistribution of solute during drying. While insights on the dynamic redistribution are instrumental for the rational design of powders and for the optimized operation of equipment such as spray dryers, experimental techniques that allow measuring...
journal article 2022
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Cheishvili, K. (author), Kalkman, J. (author)
We show scanning dynamic light scattering optical coherence tomography (OCT) omnidirectional flow measurements. Our method improves the velocity measurement limit over conventional correlation-based or phase-resolved Doppler OCT by more than a factor of 2. Our technique is applicable without a-priori knowledge of the flow geometry as our...
journal article 2022
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Balasubramani, Vinoth (author), Kujawińska, Małgorzata (author), Allier, Cédric (author), Anand, Vijayakumar (author), Cheng, Chau Jern (author), Depeursinge, Christian (author), Hai, Nathaniel (author), Kalkman, J. (author), Park, Yong Keun (author)
Quantitative Phase Imaging (QPI) provides unique means for the imaging of biological or technical microstructures, merging beneficial features identified with microscopy, interferometry, holography, and numerical computations. This roadmap article reviews several digital holography-based QPI approaches developed by prominent research groups....
review 2021
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de Wit, J. (author), Angelopoulos, Kostas (author), Kalkman, J. (author), Glentis, George Othon (author)
Spectral-estimation OCT (SE-OCT) is a computational method to enhance the axial resolution beyond the traditional bandwidth limit. However, it has not yet been used widely due to its high computational load, dependency on user-optimized parameters, and inaccuracy in intensity reconstruction. In this study, we implement SE-OCT using a fast...
journal article 2021
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Ghafaryasl, B. (author), VERMEER, KOENRAAD A. (author), Kalkman, J. (author), Dore-Callewaert, T.W.J. (author), DE BOER, JOHANNES F. (author), van Vliet, L.J. (author)
Optical properties, such as the attenuation coefficients of multi-layer tissue samples, could be used as a biomarker for diagnosis and disease progression in clinical practice. In this paper, we present a method to estimate the attenuation coefficients in a multi-layer sample by fitting a single scattering model for the OCT signal to the...
journal article 2021
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de Wit, J. (author), Tonn, Sebastian (author), van den Ackerveken, Guido (author), Kalkman, J. (author)
Optical coherence tomography (OCT) can be a valuable imaging tool for in vivo and label-free digital plant phenotyping. However, for imaging leaves, air-filled cavities limit the penetration depth and reduce the image quality. Moreover, up to now quantification of leaf morphology with OCT has been done in one-dimensional or two-dimensional...
journal article 2020
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van Rooij, J. (author), Kalkman, J. (author)
We demonstrate large scale polarization contrast optical diffraction tomography (ODT). In cross-polarized sample arm detection configuration we determine, from the amplitude of the optical wavefield, a relative measure of the birefringence projection. In parallel-polarized sample arm detection configuration we image the conventional phase...
journal article 2020
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van der Horst, J. (author), Trull, A.K. (author), Kalkman, J. (author)
In vivo imaging of small animals is of wide interest to the biomedical community studying biological disease and developmental processes. However, optical imaging deep in tissue is severely limited by light scattering, posing restrictions on the imaging depth, image contrast, and spatial resolution. We demonstrate optical coherence projection...
journal article 2020
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