Download or read book Coherent Diffractive Imaging with Enhanced Contrast Mechanisms written by Arjun Rana and published by . This book was released on 2021 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coherent diffractive imaging (CDI) is an imaging technique which uses reconstructionalgorithms in place of lenses to avoid aberration, which becomes vital in the x-ray regime. Over the last two decades, CDI has served as an invaluable tool to reveal the structure and chemical composition of a wide range of material and biological systems, providing insight across many disciplines. As part of the modern scientific frontier, CDI continues to evolve as an integral tool for the investigation of increasingly complex systems, while pushing the spatiotemporal limit. This work contains three studies which demonstrate extended capabilities of CDI through the utilization of fundamental light-matter interactions in tandem with advanced algorithms. First, the development of a novel broadband reconstruction algorithm called "Spectrum Probe and Image Reconstruction" (SPIRE) is presented in the context of attosecond imaging. An understanding of incoherent scattering permits the development of SPIRE which is shown to outperform other broadband reconstruction algorithms through the use of novel constraints. SPIRE is tested with a set of numerical simulations and a tabletop experiment with a white LED source. The results demonstrate the viability of CDI with broadband illumination and on ultrafast time scales. Second, x-ray magnetic circular dichroism (XMCD) is used to probe the magnetization of a geometrically confined ferromagnet on the nanoscale. A novel vector tomography algorithm titled "Vector REal Space Iterative Reconstruction Engine (Vector RESIRE)" is used to directly reconstruct the 3D magnetization vector field in addition to the sample structure, without any prior assumptions. Topological analysis of the reconstruction result reveals a network of non-trivial magnetic point defects known as hedgehogs. The 3D spatial distribution of hedgehogs serve to validate the current theory of hedgehog confinement and potential of metalattices in spintronics applications. In the appendix, polarization-dependent imaging contrast (PIC) is used to map the orientation of the crystal c-axis of calcium carbonate in a coral skeleton. Hierarchical clustering is applied to 4D scanning transmission electron microscope (STEM) data from the same sample to gain additional information about the crystal grain structure. The PIC and 4D STEM results are correlated to elucidate growth and nucleation conditions for coral.
Download or read book Diffraction Enhanced Imaging Contrast Mechanisms and Applications to Medicine written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nanoscale Photonic Imaging written by Tim Salditt and published by Springer Nature. This book was released on 2020-06-09 with total page 634 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book, edited and authored by a team of world-leading researchers, provides a broad overview of advanced photonic methods for nanoscale visualization, as well as describing a range of fascinating in-depth studies. Introductory chapters cover the most relevant physics and basic methods that young researchers need to master in order to work effectively in the field of nanoscale photonic imaging, from physical first principles, to instrumentation, to mathematical foundations of imaging and data analysis. Subsequent chapters demonstrate how these cutting edge methods are applied to a variety of systems, including complex fluids and biomolecular systems, for visualizing their structure and dynamics, in space and on timescales extending over many orders of magnitude down to the femtosecond range. Progress in nanoscale photonic imaging in Göttingen has been the sum total of more than a decade of work by a wide range of scientists and mathematicians across disciplines, working together in a vibrant collaboration of a kind rarely matched. This volume presents the highlights of their research achievements and serves as a record of the unique and remarkable constellation of contributors, as well as looking ahead at the future prospects in this field. It will serve not only as a useful reference for experienced researchers but also as a valuable point of entry for newcomers.
Download or read book Diffraction Enhanced Imaging Contrast Mechanisms and Applications to Medicine written by Moumen O. Hasnah and published by . This book was released on 2002 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Coherent Diffractive Imaging Using Table top Sources written by Michal Odstrčil and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Application of Diffraction Enhanced Imaging for Obtaining Improved Contrast of Calcifications in Breast Tissue written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Diffraction enhanced imaging (DEI) has been used to study the improvements in image contrast of calcifications in breast tissue. This new imaging modality has the potential to greatly improve early detection of breast cancer, primarily due to its ability to utilize contrast mechanisms in the breast, which are not possible with existing radiographic methods. Of particular interest is the comparison of the image contrast of calcifications in breast tissue obtained using DEI to those obtained using conventional radiography. The presence of calcifications in breast tissue has been connected to breast cancer, but this relationship is not well understood. The purpose of this dissertation is to study the improvements in image contrast of calcifications in healthy as well as cancerous breast tissue when using synchrotron-based DEI compared to conventional synchrotron-based methods. Image contrast is in part determined by the capabilities of the detector in the imaging system, and this relation was used to determine the effect of the limits of spatial resolution on near-pixel-sized objects, both by experiment and by computer modeling. Consistent definitions for image contrast were presented and applied to test objects, followed by application to breast tissue specimens containing calcifications. In every case, images obtained using DEI exhibited higher image contrast than the corresponding images obtained using normal radiography. The ratio of these contrast values, called the DEI gain, was consistently larger than unity, indicating that DEI does indeed utilize additional contrast mechanisms, such as refraction and scatter rejection, in addition to absorption and provides support for the development of a clinical prototype.
Download or read book Coherent X ray diffractive imaging on the single cell level of microbial samples written by Robin Niklas Wilke and published by Göttingen University Press. This book was released on 2015 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since its first experimental demonstration in 1999, Coherent X-Ray Diffractive Imaging has become one of the most promising high resolution X-Ray imaging techniques using coherent radiation produced by brilliant synchrotron storage rings. The ability to directly invert diffraction data with the help of advanced algorithms has paved the way for microscopic investigations and wave-field analyses on the spatial scale of nanometres without the need for inefficient imaging lenses. X-Ray phase contrast which is a measure of the electron density is an important contrast mode of soft biological specimens. For the case of many dominant elements of soft biological matter, the electron density can be converted into an effective mass density offering a unique quantitative information channel which may shed light on important questions such as DNA compaction in the bacterial nucleoid through ‚weighing with light‘. In this work X-Ray phase contrast maps have been obtained from different biological samples by exploring different methods. In particular, the techniques Ptychography and Waveguide-Holographic-Imaging have been used to obtain twodimensional and three-dimensional mass density maps on the single-cell-level of freeze-dried cells of the bacteria Deinococcus radiodurans, Bacillus subtilis and Bacillus thuringiensis allowing, for instance, to estimate the dry weight of the bacterial genome in a near native state. On top of this, reciprocal space information from coherent small angle X-Ray scattering (cellular Nano-Diffraction) of the fine structure of the bacterial cells has been recorded in a synergistic manner and has been analysed down to a resolution of about 2.3/nm exceeding current limits of direct imaging approaches. Furthermore, the dynamic range of present detector technology being one of the major limiting factors of ptychographic phasing of farfield diffraction data has been significantly increased. Overcoming this problem for the case of the very intense X-Ray beam produced by Kirkpatrick-Baez mirrors has been explored by using semi-transparent central stops.
Download or read book Solidification Processing of Metallic Alloys Under External Fields written by Dmitry G. Eskin and published by Springer. This book was released on 2018-10-09 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores the application of external physical fields to the solidification processing of metallic alloys. Leading academics from around the world present comprehensive and critical reviews on state-of-the-art research and discuss possible future directions. Major physical fields, including electromagnetic, electric, acoustic, and thermal, are considered. In addition, the most advanced synchrotron X-ray based real-time and in-situ studies and numerical modeling methodologies are reviewed and discussed, with a special emphasis on their applications to the solidification processes. Throughout, all chapters are illustrated with both historical and very recent research cases, including typical examples of in-situ studies, modeling, and simulation. This book contains essential knowledge and information suitable for a wide audience, from undergraduate and postgraduate students to academics, practicing researchers, and engineers in materials, metallurgy, and manufacturing.
Download or read book Partially Coherent Diffractive Imaging written by Lachlan Whitehead and published by . This book was released on 2011 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Epioptics 7 Proceedings Of The 24th Course Of The International School Of Solid State Physics written by Antonio Cricenti and published by World Scientific. This book was released on 2004-02-13 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book assesses the capabilities of state-of-the-art optical techniques in elucidating the fundamental electronic and structural properties of semiconductor and metal surfaces, interfaces, thin layers, and layer structures. It also examines the usefulness of these techniques for optimization of high quality multilayer samples through feedback control during materials growth and processing. Emphasis is given to dynamical processes through the use of pump-probe techniques, together with the search for new optical sources. Some new applications of scanning probe microscopy to materials science and biological samples (dried and in vivo) with the use of different laser sources are also presented.
Download or read book Coherent Diffractive Imaging Using Curved Beam Illumination written by H. N. Chapman and published by . This book was released on 2005 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: The potential of coherent diffractive imaging has in recent years become well recognized. In this technique an essentially parallel beam of coherent x-rays illuminates a support region containing an unknown sample. Outside that region the wavefield is known--typically the sample is isolated so that outside the support there is no scattering. When the diffraction pattern is measured with sufficient signal to noise ratio an iterative technique can be used to solve for the transmission function of the sample. The technique offers extremely high resolution reconstructions of a sample.
Download or read book Phase Contrast and Dark Field Imaging written by Simon Zabler and published by MDPI. This book was released on 2019-01-08 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Phase-Contrast and Dark-Field Imaging" that was published in J. Imaging
Download or read book Principles of Materials Characterization and Metrology written by Kannan M. Krishnan and published by Oxford University Press. This book was released on 2021-05-07 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt: Characterization enables a microscopic understanding of the fundamental properties of materials (Science) to predict their macroscopic behaviour (Engineering). With this focus, Principles of Materials Characterization and Metrology presents a comprehensive discussion of the principles of materials characterization and metrology. Characterization techniques are introduced through elementary concepts of bonding, electronic structure of molecules and solids, and the arrangement of atoms in crystals. Then, the range of electrons, photons, ions, neutrons and scanning probes, used in characterization, including their generation and related beam-solid interactions that determine or limit their use, is presented. This is followed by ion-scattering methods, optics, optical diffraction, microscopy, and ellipsometry. Generalization of Fraunhofer diffraction to scattering by a three-dimensional arrangement of atoms in crystals leads to X-ray, electron, and neutron diffraction methods, both from surfaces and the bulk. Discussion of transmission and analytical electron microscopy, including recent developments, is followed by chapters on scanning electron microscopy and scanning probe microscopies. The book concludes with elaborate tables to provide a convenient and easily accessible way of summarizing the key points, features, and inter-relatedness of the different spectroscopy, diffraction, and imaging techniques presented throughout. Principles of Materials Characterization and Metrology uniquely combines a discussion of the physical principles and practical application of these characterization techniques to explain and illustrate the fundamental properties of a wide range of materials in a tool-based approach. Based on forty years of teaching and research, this book incorporates worked examples, to test the reader's knowledge with extensive questions and exercises.
Download or read book Elements of Synchrotron Light written by Giorgio Margaritondo and published by . This book was released on 2002 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is structured by two-level presentation including a simple descriptive treatment and slightly more in-depth discussions of specific topics. The first-level treatment covers the notions, terminology and techniques that are required to use a synchrotron facility. The book is therefore an ideal first step for all those beginning to use synchrotron light for their work or are considering it. The treated topics include the basic functioning mechanisms of synchrotrons and free electron lasers a description of sychrotron-based techniques in x-ray imaging and radiology, spectroscopy, microscopy and spectromicroscopy, EXAFS, crystallography and scattering, and microfabrication.
Download or read book Advances in Fresnel Coherent Diffractive Imaging written by Jesse Norman Clark and published by . This book was released on 2010 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Epioptics 7 written by Antonio Cricenti and published by World Scientific. This book was released on 2004 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This special volume of World Scientific contains the Proceedings of the 7th Epioptics Workshop held in the Ettore Majorana Foundation and Centre for Scientific Culture, Erice, Sicily, from July 20 to 26, 2002. The Workshop was the 7th in the Epioptics series and the 24th of the International School of Solid State Physics"--P. v.
Download or read book A Generalised Holographic Approach to Coherent Diffractive Imaging written by Andrew James Morgan and published by . This book was released on 2013 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt:
