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An account of the early history of scanning electron microscopy has been presented by McMullan. [2] [3] Although Max Knoll produced a photo with a 50 mm object-field-width showing channeling contrast by the use of an electron beam scanner, [4] it was Manfred von Ardenne who in 1937 invented [5] a microscope with high resolution by scanning a very small raster with a demagnified and finely ...
Then, magnified tomographic images of the emulsions, which correspond to the x-ray opacity maps of the specimen, are recorded using a light microscope or an electron microscope. A unique advantage that X-ray contact imaging offered over electron microscopy was the ability to image wet biological materials.
The main approaches involved converting the electron optical column of an electron microscope into a transmission x-ray tube, using micro-focusing x-ray tubes, combining x-ray tubes with capillary techniques, as well as combining x-ray tubes with monochromators and applying synchrotron radiation. [6]
Energy-dispersive X-ray spectroscopy (EDS, EDX, EDXS or XEDS), sometimes called energy dispersive X-ray analysis (EDXA or EDAX) or energy dispersive X-ray microanalysis (EDXMA), is an analytical technique used for the elemental analysis or chemical characterization of a sample. It relies on an interaction of some source of X-ray excitation and ...
X-ray optics is the branch of optics dealing with X-rays, rather than visible light.It deals with focusing and other ways of manipulating the X-ray beams for research techniques such as X-ray diffraction, X-ray crystallography, X-ray fluorescence, small-angle X-ray scattering, X-ray microscopy, X-ray phase-contrast imaging, and X-ray astronomy.
Reproduction of an early electron microscope constructed by Ernst Ruska in the 1930s. Many developments laid the groundwork of the electron optics used in microscopes. [2] One significant step was the work of Hertz in 1883 [3] who made a cathode-ray tube with electrostatic and magnetic deflection, demonstrating manipulation of the direction of an electron beam.
Typical X-ray detectors for electron microscopes cover only a small solid angle, which makes X-ray detection relatively inefficient since X-rays are emitted from the sample in every direction. However, detectors covering large solid angles have been recently developed, [27] and atomic resolution X-ray mapping has even been achieved. [28]
Electron beam computed tomography (EBCT) is a fifth generation computed tomography (CT) scanner in which the X-ray tube is not mechanically spun in order to rotate the source of X-ray photons. This different design was explicitly developed to better image heart structures that never stop moving, performing a complete cycle of movement with each ...