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Diffraction in neutron imaging—A review
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2018Abstract Neutron imaging is a highly successful experimental technique ever since adequate neutron sources were available. In general, neutron imaging is performed with a wide wavelength spectrum for best flux conditions in transmission geometry. Neutrons provide outstanding features in the penetration of many structural materials, which often makes ...
Woracek, Robin +3 more
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Magnetic resonance diffractive imaging
IEEE Transactions on Biomedical Engineering, 2002Magnetic resonance (MR) diffractive imaging is proposed as a new approach to MR angiography. The expression of the nuclear MR signal is similar to the equation for the Fresnel diffraction of a three-dimensional (3-D) object in light or sound waves. The proposed technique offers the possibility of fast angiographic imaging and the on-line reconstruction
Satoshi Ito +2 more
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Diffraction elimination of slow images
CLEO/Europe - EQEC 2009 - European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference, 2009All classical wave fields are subjected to diffraction throughout their propagation. In many systems, a reduction or elimination of the diffraction spreading of beamlike fields are obtained by manipulating the susceptibility in real space and inducing a gradient of the index of refraction. Similarly to wave-guiding, only specific modes may propagate in
O. Firstenberg +3 more
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Dynamic sample imaging in coherent diffractive imaging
Optics Letters, 2011As the resolution in coherent diffractive imaging improves, interexposure and intraexposure sample dynamics, such as motion, degrade the quality of the reconstructed image. Selecting data sets that include only exposures where tolerably little motion has occurred is an inefficient use of time and flux, especially when detector readout time is ...
Jesse N, Clark +7 more
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Optical image encryption based on diffractive imaging
Optics Letters, 2010In this Letter, we propose a method for optical image encryption based on diffractive imaging. An optical multiple random phase mask encoding system is applied, and one of the phase-only masks is selected and laterally translated along a preset direction during the encryption process.
Chen, W., Chen, X., Sheppard, C.J.R.
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2016
In this chapter, we discuss two subjects in which diffraction is the dominant process in image formation. The first argument, developed in the first two sections, is the Abbe theory of image formation. The theory is valid in general, but is easier to understand under conditions of coherence.
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In this chapter, we discuss two subjects in which diffraction is the dominant process in image formation. The first argument, developed in the first two sections, is the Abbe theory of image formation. The theory is valid in general, but is easier to understand under conditions of coherence.
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High-contrast imaging for weakly diffracting specimens in coherent diffraction imaging
Chinese Optics Letters, 2013Coherent diffraction imaging (CDI) and ptychography techniques bypass the difficulty of having highquality optics in X-ray microscopy by using a numerical reconstruction of the image that is obtained by inverting the diffracted intensity recorded by a charge-coupled device array. However, the reconstruction of the image from the intensity data obtained
Xingchen Pan Xingchen Pan +4 more
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Reciprocity in Electron Diffraction and Imaging
1995In electron imaging, TEM and STEM are considered to be equivalent, so that images obtained in both optic configurations have many analogous characteristics, and sometimes they can be interpreted using the same theory. This analogy is based on the reciprocity theorem, which is stated as: The amplitude of the disturbance at a point P due to radiation ...
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Diffraction Apparatus for X-Ray Diffraction Imaging
2018To visualize the structures of frozen-hydrated non-crystalline biological particles such as cells and organelles, two types of diffraction apparatus were developed for X-ray diffraction imaging (XDI) experiments at cryogenic temperatures using synchrotron X-rays and X-ray free electron laser (XFEL) pulses. Cryogenic experiments are advantageous for the
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