![]() Femtosecond diffractive imaging with a soft-X-ray free-electron laser. ![]() Ptychographic X-ray computed tomography at the nanoscale. High-resolution scanning x-ray diffraction microscopy. An assessment of the resolution limitation due to radiation-damage in x-ray diffraction microscopy. High-resolution ab initio three-dimensional x-ray diffraction microscopy. Three-dimensional electron density mapping of shape-controlled nanoparticle by focused hard X-ray diffraction microscopy. Three-dimensional visualization of a human chromosome using coherent X-ray diffraction. Nishino, Y., Takahashi, Y., Imamoto, N., Ishikawa, T. Beyond crystallography: diffractive imaging using coherent x-ray light sources. Ultrafast single-shot diffraction imaging of nanoscale dynamics. Single-shot femtosecond X-ray holography using extended references. Single-shot diffractive imaging with a table-top femtosecond soft X-ray laser-harmonics source. Natively inhibited Trypanosoma brucei cathepsin B structure determined by using an X-ray laser. Single mimivirus particles intercepted and imaged with an X-ray laser. Computed stereo X-ray imaging will find application at X-ray free-electron lasers, synchrotrons and laser-based sources, and in industrial and medical 3D diagnosis methods. We also show that by using nanoparticles as labels we can extend the applicability of the technique to complex samples. We demonstrate that phase-contrast images relax the disparity constraints, allowing occulted features to be revealed. Similarly to brain perception, computed stereo vision algorithms use constraints. We reconstruct two X-ray stereo views from coherent diffraction patterns and compute a nanoscale 3D representation of the sample from disparity maps. Stereo vision is important in the field of machine vision and robotics. Here we show that computed stereo vision concepts can be applied to X-rays. The requirement for a low X-ray dose also prevents single-shot 3D imaging using ultrafast X-ray sources. A few examples illustrate the possibilities of coherent X-rays for imaging and intensity correlation spectroscopy.Recovering the three-dimensional (3D) properties of artificial or biological systems using low X-ray doses is challenging as most techniques are based on computing hundreds of two-dimensional (2D) projections. A comparison between X-ray scattering, neutron scattering and mesoscopic electron transport is given. The loss of interference due to the finite detection time, to the finite detector pixel size and to uncontrolled degrees of freedom in the sample is discussed at length. Otherwise, a configurational average washes out the speckle and only diffuse scattering and possibly Bragg reflections will survive. When the illuminated sample volume is smaller than the coherence volume, the individuality of the defect arrangement in a sample shows up as speckle in the scattered intensity. The concept of coherence volume, defined in quantum optics terms, is generalized for scattering experiments. Their characterization in terms of coherence functions of the first and second order is introduced. All the currently available X-ray sources are chaotic sources. It has become possible to image opaque objects in phase contrast with a sensitivity far superior to imaging in absorption contrast. ![]() Speckle spectroscopy is extended to hard X-rays, improving the resolution to the nm range. Coherent X-rays are characterized by a large lateral coherence length. Highly brilliant synchrotron radiation sources have opened up the possibility of using coherent X-rays in spectroscopy and imaging.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |