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Holographic microscopy

Mehdi Molaei, Jian Sheng
Understanding how bacteria move close to a surface under various stimuli is crucial for a broad range of microbial processes including biofilm formation, bacterial transport and migration. While prior studies focus on interactions between single stimulus and bacterial suspension, we emphasize on compounding effects of flow shear and solid surfaces on bacterial motility, especially reorientation and tumble. We have applied microfluidics and digital holographic microscopy to capture a large number (>10(5)) of 3D Escherichia coli trajectories near a surface under various flow shear...
October 18, 2016: Scientific Reports
Anna Wang, Ryan McGorty, David M Kaz, Vinothan N Manoharan
Previous experiments have shown that spherical colloidal particles relax to equilibrium slowly after they adsorb to a liquid-liquid interface, despite the large interfacial energy gradient driving the adsorption. The slow relaxation has been explained in terms of transient pinning and depinning of the contact line on the surface of the particles. However, the nature of the pinning sites has not been investigated in detail. We use digital holographic microscopy to track a variety of colloidal spheres-inorganic and organic, charge-stabilized and sterically stabilized, aqueous and non-aqueous-as they breach liquid interfaces...
October 13, 2016: Soft Matter
Khaled M Yassien, Mostafa Agour
A method for studying the effect of temperature on the optical properties of basalt fiber is presented. It is based on recording a set of phase-shifted digital holograms for the sample under the test. The holograms are obtained utilizing a system based on Mach-Zehnder interferometer, where the fiber sample inserted in an immersion liquid is placed within a temperature controlled chamber. From the recorded digital holograms the optical path differences which are used to calculate the refractive indices are determined...
October 11, 2016: Microscopy Research and Technique
Chen Wang, Fook Chiong Cheong, David B Ruffner, Xiao Zhong, Michael D Ward, David G Grier
In-line holographic microscopy images of micrometer-scale fractal aggregates can be interpreted with an effective-sphere model to obtain each aggregate's size and the population-averaged fractal dimension. We demonstrate this technique experimentally using model fractal clusters of polystyrene nanoparticles and fractal protein aggregates composed of bovine serum albumin and bovine pancreas insulin.
October 5, 2016: Soft Matter
Alborz Feizi, Yibo Zhang, Alon Greenbaum, Alex Guziak, Michelle Luong, Raymond Yan Lok Chan, Brandon Berg, Haydar Ozkan, Wei Luo, Michael Wu, Yichen Wu, Aydogan Ozcan
Monitoring yeast cell viability and concentration is important in brewing, baking and biofuel production. However, existing methods of measuring viability and concentration are relatively bulky, tedious and expensive. Here we demonstrate a compact and cost-effective automatic yeast analysis platform (AYAP), which can rapidly measure cell concentration and viability. AYAP is based on digital in-line holography and on-chip microscopy and rapidly images a large field-of-view of 22.5 mm(2). This lens-free microscope weighs 70 g and utilizes a partially-coherent illumination source and an opto-electronic image sensor chip...
September 30, 2016: Lab on a Chip
Philipp Lenz, Markus Brückner, Steffi Ketelhut, Jan Heidemann, Björn Kemper, Dominik Bettenworth
The incidence of inflammatory bowel disease, i.e., Crohn's disease and Ulcerative colitis, has significantly increased over the last decade. The etiology of IBD remains unknown and current therapeutic strategies are based on the unspecific suppression of the immune system. The development of treatments that specifically target intestinal inflammation and epithelial wound healing could significantly improve management of IBD, however this requires accurate detection of inflammatory changes. Currently, potential drug candidates are usually evaluated using animal models in vivo or with cell culture based techniques in vitro...
2016: Journal of Visualized Experiments: JoVE
C Grassberger, P Dinkelborg, A McNamara, J P Schuemann, S J McMahon, H Willers, H Paganetti, M Wang
No abstract text is available yet for this article.
October 1, 2016: International Journal of Radiation Oncology, Biology, Physics
Jianglei Di, Ying Li, Min Xie, Jiwei Zhang, Chaojie Ma, Teli Xi, Enpu Li, Jianlin Zhao
A dual-wavelength common-path digital holographic microscopy based on a single parallel glass plate is presented to achieve quantitative phase imaging, which combines the dual-wavelength technique with lateral shearing interferometry. Two illumination laser beams with different wavelengths (λ<sub>1</sub>=532  nm and λ<sub>2</sub>=632.8  nm) are reflected by the front and back surfaces of the parallel glass plate to create the lateral shear and form the digital hologram, and then the hologram is reconstructed to obtain the phase distribution with a synthetic wavelength Λ=3339...
September 10, 2016: Applied Optics
Maciej Trusiak, Vicente Mico, Javier Garcia, Krzysztof Patorski
We propose a novel single-shot Hilbert-Huang transform-based algorithm applied to digital holographic microscopy (DHM) for robust, fast, and accurate single-shot quantitative phase imaging in on-axis and off-axis configurations. Fringe pattern with possible defects and closed fringes are adaptively filtered and accurately phase demodulated using local fringe direction estimation. Experimental validation of the proposed techniques is presented as the DHM study of microbeads and red blood cells phase samples...
September 15, 2016: Optics Letters
Jérôme Dohet-Eraly, Catherine Yourassowsky, Frank Dubois
The knowledge of the complex amplitude of optical fields, that is, both quantitative phase and intensity, enables numeric reconstruction along the optical axis. Nonetheless, a criterion is required for autofocusing. This Letter presents a robust and rapid refocusing criterion suitable for color interferometric digital holographic microscopy, and, more generally, for applications where complex amplitude is known for at least two different wavelengths. This criterion uses the phase in the Fourier domain, which is compared among wavelengths...
September 1, 2016: Optics Letters
Kyoohyun Kim, Kibaek Choe, Inwon Park, Pilhan Kim, YongKeun Park
Intravital microscopy is an essential tool that reveals behaviours of live cells under conditions close to natural physiological states. So far, although various approaches for imaging cells in vivo have been proposed, most require the use of labelling and also provide only qualitative imaging information. Holographic imaging approach based on measuring the refractive index distributions of cells, however, circumvent these problems and offer quantitative and label-free imaging capability. Here, we demonstrate in vivo two- and three-dimensional holographic imaging of circulating blood cells in intact microcapillaries of live mice...
2016: Scientific Reports
Vitor Brasiliense, Pascal Berto, Catherine Combellas, Gilles Tessier, Frédéric Kanoufi
Interest in nanoparticles has vigorously increased over the last 20 years as more and more studies show how their use can potentially revolutionize science and technology. Their applications span many different academically and industrially relevant fields such as catalysis, materials science, health, etc. Until the past decade, however, nanoparticle studies mostly relied on ensemble studies, thus leaving aside their chemical heterogeneity at the single particle level. Over the past few years, powerful new tools appeared to probe nanoparticles individually and in situ...
September 20, 2016: Accounts of Chemical Research
F Kern, D Wolf, P Pschera, A Lubk
Off-axis electron holography is a well-established transmission electron microscopy technique, typically employed to investigate electric and magnetic fields in and around nanoscale materials, which modify the phase of the reconstructed electron wave function. Here, we elaborate on a detailed analysis of the two characteristic intensity terms that are completing the electron hologram, the conventional image intensity and the interference fringe intensity. We show how both are related to elastic and inelastic scattering absorption at the sample and how they may be separated to analyze the chemical composition of the sample...
August 23, 2016: Ultramicroscopy
Tomoyuki Kawase, Kazuhiro Okuda, Masaki Nagata, Makoto Tsuchimochi, Hiromasa Yoshie, Koh Nakata
Purpose To assure the quality of cells to be used in cell therapy, we examined the applicability of digital holographic microscopy (DHM) for non-invasive, quantitative assessment of changes in cell morphology. Materials and methods Mesenchymal stem cells derived from adipose tissue (MSC-AT) and bone marrow (MSC-BM), in addition to human alveolar periosteal cells (PCs) as a reference, were γ-ray irradiated (1 and 4 Gy), and their morphological changes were quantified without fixation using holographic microscopy...
September 1, 2016: International Journal of Radiation Biology
Xuefei He, Chuong Vinh Nguyen, Mrinalini Pratap, Yujie Zheng, Yi Wang, David R Nisbet, Richard J Williams, Melanie Rug, Alexander G Maier, Woei Ming Lee
Automated label-free quantitative imaging of biological samples can greatly benefit high throughput diseases diagnosis. Digital holographic microscopy (DHM) is a powerful quantitative label-free imaging tool that retrieves structural details of cellular samples non-invasively. In off-axis DHM, a proper spatial filtering window in Fourier space is crucial to the quality of reconstructed phase image. Here we describe a region-recognition approach that combines shape recognition with an iterative thresholding method to extracts the optimal shape of frequency components...
August 1, 2016: Biomedical Optics Express
Jorge Garcia-Sucerquia
A comparison of the performance of color digital lensless holographic microscopy (CDLHM) as utilized for illumination of RGB lasers or a super-bright white-light LED with a set of spectral filters is presented. As the use of lasers in CDLHM conceals the possibility of having a compact, lightweight, portable, and low cost microscope, and additionally the limited available laser radiation wavelengths limit a real multispectral imaging microscope, here we present the use of super-bright white-light LED and spectral filters for illuminating the sample...
August 20, 2016: Applied Optics
Juan C Aguilar, Masaki Misawa, Kiyofumi Matsuda, Shakil Rehman, Masato Yasumoto, Yoshio Suzuki, Akihisa Takeuchi, L R Berriel-Valdos
In this paper, we show how the starlet transform can be used to process holograms from a digital Gabor holographic microscope. The starlet transform is an undecimated wavelet transform with the property that when performing reconstruction, we only need to add all scales without the use of a synthesis filter bank. When the starlet transform is applied to a hologram, we divide the hologram into a certain number of scales, process them separately, and propagate each one using a numerical diffraction method. After diffraction propagation, we perform processing on complex amplitudes that correspond to individual scales...
August 20, 2016: Applied Optics
Tobias Meinert, Olaf Tietz, Klaus J Palme, Alexander Rohrbach
Image quality in light-sheet fluorescence microscopy is strongly affected by the shape of the illuminating laser beam inside embryos, plants or tissue. While the phase of Gaussian or Bessel beams propagating through thousands of cells can be partly controlled holographically, the propagation of fluorescence light to the detector is difficult to control. With each scatter process a fluorescence photon loses information necessary for the image generation. Using Arabidopsis root tips we demonstrate that ballistic and diffusive fluorescence photons can be separated by analyzing the image spectra in each plane without a priori knowledge...
2016: Scientific Reports
Jiwei Zhang, Chaojie Ma, Siqing Dai, Jianglei Di, Ying Li, Teli Xi, Jianlin Zhao
We develop a transmission and total internal reflection (TIR) integrated digital holographic microscopy (DHM) by introducing a home-made Dove prism with a polished short side. With the help of angular and polarization multiplexing techniques, the 2D refractive index distribution of a specimen adhered on the prism surface is determined using TIR-DHM. Meanwhile, the thickness profile is unambiguously calculated from the phase information using transmission DHM. This integrated microscopy is nondestructive and dynamic and can be used to simultaneously measure the index distribution and thickness profile of transparent or semi-transparent liquid or solid samples...
August 15, 2016: Optics Letters
Zhe Wang, Zhuqing Jiang, Yifei Chen
A new system for single-shot dual-wavelength digital holographic microscopy with polarization-multiplexing path-shared transmission is presented. The key feature of the optical configuration is that the interference waves of two wavelengths having orthogonal polarization can transmit in the same interferometer paths at the same time, and two polarizers orthogonal to each other are placed in front of the CCD to realize single-shot recording of two holograms. The correlative filtering algorithm of the spatial-frequency spectrum for dual-wavelength digital holograms is reliable and efficient in the dual-wavelength path-shared configuration...
August 1, 2016: Applied Optics
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