Download or read book Holography at X ray Wavelengths written by and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We discuss alternative holographic techniques for imaging microscopic structures with a short-pulse, high intensity, high-quantum-energy laser. We find that Fresnel transform holography using a photoresist for registration of the hologram is most likely to be within the scope of near term technology. Although it has advantages in time gating, using an in-line electron microscope for hologram registration has an unacceptable tradeoff between quantum efficiency and resolution. Fourier transform holography using a reflector to generate the reference beam might be a reasonable alternative using low resolution film, but is necessarily more complicated. We discuss the dependence of the required laser intensity on the resolution sought and on the elastic and absorption cross sections. We conclude that resonant scattering must be used to obtain holograms at reasonable intensities.
Download or read book Radiation Damage and Its Influence on Source Requirements for High Resolution X ray Holography written by and published by . This book was released on 1989 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soft x-ray holography offers the possibility of obtaining high resolution, 3-D images of living cells and organelles therein. To achieve a specified resolution, a certain number of photons must be scattered by the smallest features of interest within the sample. This requires a certain irradiating fluence, the magnitude of which depends on the wavelength of the x rays and the scattering cross- sections of the features. Unfortunately, irradiation of the sample will be accompanied by the absorption of x rays. If the dose is large, the sample will be damaged, possibly compromising the quality of the image. A theoretical study of the scattering and absorption of x rays during the creation of a hologram is described. Using a new prescription for scattering by condensed biological materials (e.g., protein and/or DNA) within the aqueous environment of a cell, we estimate the irradiating fluence required for a certain resolution and the associated sample dose. The relative merits of different x-ray wavelengths are discussed. A wavelength of about 44Å, just outside the water window'' (23.2--43.7Å), appears to be optimal in that the required fluence and dose are minimized, while reasonable x-ray penetrability is maintained. Estimates are given for the minimum source energy required and the maximum duration of an exposure to capture an image before blurring due heat induce motion. The use of colloidal gold tagging can enhance image contrast and reduce the required irradiating fluence and sample damage. 6 refs., 5 figs.
Download or read book Curiosity Oriented Research written by R. D. Medford and published by . This book was released on 1974 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lensless Holography Methods for Soft X ray Resonant Coherent Imaging written by Diling Zhu and published by Stanford University. This book was released on 2010 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ability to interpret and inverse x-ray diffraction patterns from crystals has largely shaped our understanding of the structure of matter. However, structure determination of noncrystalline objects from their diffraction patterns is a much more difficult task. The dramatic increase in available coherent x-ray photon flux over the past decade has made possible a technique known as lensless coherent diffractive imaging (CDI), that addresses exactly this problem. The central question around CDI is the so-called phase problem: upon detection of the diffraction intensity, the phase information of the diffracted wave is inevitably lost. Generally, the phase problem is approached using iterative phase retrieval algorithms. Holographic methods, through interference with reference diffractions, encode the phase information directly inside the measured x-ray holograms, and are therefore able to avoid the stagnation and uniqueness problems commonly encountered by the iterative algorithms. This dissertation discusses two novel holographic methods for coherent lensless imaging using resonant soft x-rays. The first part focuses on generalizing the multiple-wavelength anomalous diffraction technique, a highly successful method for solving the crystal structures of biomacromolecules, into a multiple-wavelength holography technique for nanoscale resonant x-ray imaging. Using this method I show element specific reconstructions of nanoparticles and magnetization distribution in magnetic thin films with sub 50 nm resolution. The second part discusses progress in X-ray Fourier holography, an ultrafast lensless imaging platform that can be used with the upcoming x-ray free electron lasers. In particular, I will present experiments using two novel types of extended reference structures that bring the resolution beyond the precision of reference fabrication, previously regarded as the resolution limit for x-ray Fourier transform holography. Finally, future applications of holographic methods, especially experimental considerations for time-resolved studies of nanostructures using X-FELs, will be discussed.
Download or read book Introduction to Holography written by Vincent Toal and published by CRC Press. This book was released on 2022-12-13 with total page 449 pages. Available in PDF, EPUB and Kindle. Book excerpt: This fully updated second edition of Introduction to Holography provides a theoretical background in optics and holography with a comprehensive survey of practical applications. It is intended for the non-specialist with an interest in using holographic methods in research and engineering. The text assumes some knowledge of electromagnetism, although this is not essential for an understanding of optics, which is covered in the first two chapters. A descriptive approach to the history and principles of holography is followed by a chapter on volume holography. Essential practical requirements for successful holographic recording are explained in detail. Recording materials are considered with detailed discussions of those in common use. Properties peculiar to holographically reconstructed images are emphasised as well as applications for which holography is particularly suitable. Mathematical tools are introduced as and when required throughout the text with important results derived in detail. In this new edition, topics such as photopolymers, dynamic holographic displays, holographic optical elements, sensors, and digital holography are covered in greater depth. New topics have been added, including UV and infrared holography, holographic authentication and encryption, as well as particle beam, X-ray, and acoustic holography. Numerical problems are provided at the end of each chapter. This book is suitable for undergraduate courses and will be an important resource for those teaching optics and holography. It provides scientists and engineers with knowledge of a wide range of holographic applications in research and industry, as well as an understanding of holography’s potential for future use.
Download or read book Holographic Materials and Optical Systems written by Izabela Naydenova and published by BoD – Books on Demand. This book was released on 2017-03-22 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: Holographic Materials and Optical Systems covers recent research achievements in the areas of volume holographic optical elements and systems, development of functionalized holographic recording materials, and applications in holographic imaging and metrology. Designs of single and multiplexed volume holographic optical elements for laser beam shaping, combining, and redirection are covered, and their properties are studied theoretically and experimentally. The high impact of holography in imaging and metrology is demonstrated by applications spreading from thickness and surface measurements, through antenna metrology and analyzing high-density gradients in fluid mechanics to characterization of live objects in clinical diagnostics. Novel functionalized materials used in dynamic or permanent holographic recording cover photopolymers, photochromics, photo-thermo-refractive glasses, and hybrid organic-inorganic media.
Download or read book Practical Holography written by Graham Saxby and published by CRC Press. This book was released on 2015-09-22 with total page 690 pages. Available in PDF, EPUB and Kindle. Book excerpt: Continuing in the steps of its predecessors, the fourth edition of Practical Holography provides the most comprehensive and up-to-date resource available. Focused on practical techniques in holography at all levels, it avoids any unnecessary mathematical theory.Features of the Fourth EditionHighlights new information on color holograms, sensitive m
Download or read book Method and Apparatus for Molecular Imaging Using X rays at Resonance Wavelengths written by and published by . This book was released on 1985 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Holographic X-ray images are produced representing the molecular structure of a microscopic object, such as a living cell, by directing a beam of coherent X-rays upon the object to produce scattering of the X-rays by the object, producing interference on a recording medium between the scattered X-rays from the object and unscattered coherent X-rays and thereby producing holograms on the recording surface, and establishing the wavelength of the coherent X-rays to correspond with a molecular resonance of a constituent of such object and thereby greatly improving the contrast, sensitivity and resolution of the holograms as representations of molecular structures involving such constituent. For example, the coherent X-rays may be adjusted to the molecular resonant absorption line of nitrogen at about 401.3 eV to produce holographic images featuring molecular structures involving nitrogen.
Download or read book Synchrotron Light Sources and Free Electron Lasers written by Eberhard J. Jaeschke and published by Springer. This book was released on 2016-05-27 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hardly any other discovery of the nineteenth century did have such an impact on science and technology as Wilhelm Conrad Röntgen’s seminal find of the X-rays. X-ray tubes soon made their way as excellent instruments for numerous applications in medicine, biology, materials science and testing, chemistry and public security. Developing new radiation sources with higher brilliance and much extended spectral range resulted in stunning developments like the electron synchrotron and electron storage ring and the freeelectron laser. This handbook highlights these developments in fifty chapters. The reader is given not only an inside view of exciting science areas but also of design concepts for the most advanced light sources. The theory of synchrotron radiation and of the freeelectron laser, design examples and the technology basis are presented. The handbook presents advanced concepts like seeding and harmonic generation, the booming field of Terahertz radiation sources and upcoming brilliant light sources driven by laser-plasma accelerators. The applications of the most advanced light sources and the advent of nanobeams and fully coherent x-rays allow experiments from which scientists in the past could not even dream. Examples are the diffraction with nanometer resolution, imaging with a full 3D reconstruction of the object from a diffraction pattern, measuring the disorder in liquids with high spatial and temporal resolution. The 20th century was dedicated to the development and improvement of synchrotron light sources with an ever ongoing increase of brilliance. With ultrahigh brilliance sources, the 21st century will be the century of x-ray lasers and their applications. Thus, we are already close to the dream of condensed matter and biophysics: imaging single (macro)molecules and measuring their dynamics on the femtosecond timescale to produce movies with atomic resolution.
Download or read book Optical Holography written by Robert Collier and published by Elsevier. This book was released on 2013-06-11 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical Holography deals with the use of optical holography to solve technical problems, with emphasis on the properties of holograms formed with visible light. Topics covered include the Fourier transform, propagation and diffraction, pulsed-laser holography, and optical systems with spherical lenses. A geometric analysis of point-source holograms is also presented, and holograms and hologram spatial filters formed with spatially modulated reference waves are described. This book is comprised of 20 chapters and begins with an introduction to concepts that are basic to understanding holography, from interference patterns and diffraction to hologram formation, basic holography equations, and partial coherence. The next chapter focuses on early developments in holography, paying particular attention to Bragg's X-ray microscope, X-ray holography, and the beginnings of optical holography. The discussion then turns to light sources for hologram formation; analysis of plane holograms; diffraction from volume holograms; and real-image applications of holographic methods. The remaining chapters explore holographic interferometry, color holography, and computer-generated holograms. The final chapter deals with hologram replication, television transmission of holograms, and formation of holograms using spatially incoherent subject light. This monograph will be a useful resource for electron microscopists, electrical engineers, opticists, physicists, chemists, and others interested in optical holography.
Download or read book Femtosecond Time Delay X Ray Holography written by and published by . This book was released on 2007 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: X-ray free-electron lasers (XFELs) will produce photon pulses with a unique and desirable combination of properties. Their short X-ray wavelengths allow penetration into materials and the ability to probe structure at and below the nanometer scale. Their ultra-short duration gives information about this structure at the fundamental time-scales of atoms and molecules. The extreme intensity of the pulses will allow this information to be acquired in a single shot, so that these studies can be carried out on non-repeatable processes or on weakly-scattering objects that will be modified by the pulse. A fourth property of XFEL pulses is their high transverse coherence, which brings the promise of decades of innovation in visible optics to the X-ray regime, such as holography, interferometry, and laser-based imaging. Making an effective use of XFEL pulses, however, will benefit from innovations that are new to both X-ray science and coherent optics. One such innovation is the new method of time-delay X-ray holography [1], recently demonstrated at the FLASH FEL at DESY in Hamburg, to measure the evolution of objects irradiated by intense pulses. One of the pressing questions about the high-resolution XFEL imaging and characterization of non-periodic or weakly-scattering objects is the effect of the intense FEL pulse on the object, during the interaction with that pulse. The method of single-particle diffraction imaging [2] requires a stream of reproducible particles (e.g. a protein complex or virus) inserted into the beam, whereby a coherent X-ray diffraction pattern is recorded. The pulse will completely destroy the object, but if the pulse is short enough the diffraction pattern will represent the undamaged object. This ultrafast flash imaging was demonstrated at the FLASH FEL using test objects that included microfabricated patterns in silicon nitride foils [3]. Those experiments showed that no damage occurred during the 30 fs duration pulse. However, in those experiments the imaging resolution was limited by the long 32 nm wavelength at which the facility was then operating. We wished to dramatically increase our sensitivity to the particles explosions, to be able to increase the understanding of the dynamics of particles and predict the imaging performance at XFELs such as the LCLS. This was done in two ways in a single experiment: by holographically measuring the time evolution of the particle at times after the pulse had pass through the object; and by making an interferometric measurement of the change in the optical path through the object. The experimental technique, time-delay holography, achieved a time resolution better than 3 fs, and a phase sensitivity of better than 3{sup o}, or a sensitivity of
Download or read book Selected Papers on Fundamental Techniques in Holography written by Hans I. Bjelkhagen and published by SPIE-International Society for Optical Engineering. This book was released on 2001 with total page 776 pages. Available in PDF, EPUB and Kindle. Book excerpt: This authoritative holography text contains a collection of foundational papers written by the field's greatest scientists and engineers.
Download or read book Holographic X ray Detection written by George Kiyoshi Herring and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The ability to non-destructively image the interior of an object with X-rays has enabled huge advances in science and medicine. X-ray differential phase contrast (DPC) is the next generation in imaging, providing higher contrast for soft materials. However, X-ray DPC suffers from poor X-ray detector resolution. Typical commercial detectors have a fundamental physical tradeoff between image resolution and radiation dose. In this dissertation, I present a new method for X-ray detection that overcomes this fundamental limit. This new method uses photo refractive materials from the field of holography to create a high resolution detector which can, in conjunction with X-ray DPC techniques, measure the absorption and refraction of X-rays as they pass through objects. This new detector operates in three main stages: first, interfering X-rays record a hologram into a photorefractive crystal. Then, this crystal is illuminated with visible light to 'read-out' and digitally record the image. Finally, the crystal is erased with ultraviolet light after the image is collected. The result is an X-ray detector with an order of magnitude improvement in resolution (to 208 lp/mm), an order of magnitude improvement in quantum efficiency (to 80%), and a drastic reduction in production cost.
Download or read book X ray Lithography Using Holographic Images written by and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A non-contact X-ray projection lithography method for producing a desired X-ray image on a selected surface of an X-ray-sensitive material, such as photoresist material on a wafer, the desired X-ray image having image minimum linewidths as small as 0.063 .mu.m, or even smaller. A hologram and its position are determined that will produce the desired image on the selected surface when the hologram is irradiated with X-rays from a suitably monochromatic X-ray source of a selected wavelength .lambda. On-axis X-ray transmission through, or off-axis X-ray reflection from, a hologram may be used here, with very different requirements for monochromaticity, flux and brightness of the X-ray source. For reasonable penetration of photoresist materials by X-rays produced by the X-ray source, the wavelength X, is preferably chosen to be no more than 13.5 nm in one embodiment and more preferably is chosen in the range 1-5 nm in the other embodiment. A lower limit on linewidth is set by the linewidth of available microstructure writing devices, such as an electron beam.
Download or read book X Ray Lasers 2006 written by P.V. Nickles and published by Springer Science & Business Media. This book was released on 2008-01-18 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt: The search for table-top and repetitive pump schemes during the last decade has been the driving force behind the spectacular advances demonstrated during the 10th International Conference on X-Ray Lasers, organized in 2006 in Berlin. The proceedings of this series of conferences constitute a comprehensive source of reference of the acknowledged state-of the-art in this specific area of laser and plasma physics.
Download or read book X ray Near field Holography written by Johannes Hagemann and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: All images are flawed, no matter how good your lenses, mirrors etc. are. Especially in the hard X-ray regime it is challenging to manufacture high quality optics due to the weak interaction of multi-keV photons with matter. This is a tremendous challenge for obtaining high resolution quantitative X-ray microscopy images. In recent years lensless phase contrast imaging has become an alternative to classical absorption-based imaging methods. Without any optics, the image is formed only by the free space propagation of the wave field. The actual image has to be formed posteriori by numerical r...
Download or read book The Complete Book of Holograms written by Joseph E. Kasper and published by Courier Corporation. This book was released on 2012-07-04 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clear, thorough account, without complicated mathematics, explains geometric and zone plate holography and the different types of holograms, along with step-by-step instructions for making holograms. 116 illustrations.
