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An x‐ray source with focal spot scanning
X-Ray Spectrometry, 1980Abstract The construction of a demountable X‐Ray tube with focal spot scanning intended for operation as an X‐ray source in scanning X‐ray microscopes is described.
B. F. Belyaev +3 more
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Spot-Scan Imaging in Transmission Electron Microscopy
Science, 1991The determination of the structure of proteins and other organic materials by transmission electron microscopy is a rapidly developing field. Obtaining high-resolution images of these radiation-sensitive specimens has, until recently, been problematic. The development of spot-scan imaging, in which the electron beam is focused to a spot with a diameter
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Spot scanning for 250 MeV protons.
Strahlentherapie und Onkologie : Organ der Deutschen Rontgengesellschaft ... [et al], 1990Protons have a long tradition in precision treatment of lesions of limited size at limited depth. Recently interest has developed in hospital based proton therapy accelerators, able to treat deep seated tumors. Heavy charged particles, and especially protons, are particularly suited to treat well localized tumors. Protons can be collimated as precisely
Blattmann, H. +3 more
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Modern flying spot scanning tubes
Displays, 1979Abstract A cathode ray tube to produce a flying spot is discussed emphasizing the problems posed by the main parameters of the idea. Only the tube used in colour telecine applications is studied, as this encompasses the hurdles facing other scanning requirements.
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Monte Carlo dose calculations for spot scanned proton therapy
Physics in Medicine and Biology, 2005Density heterogeneities can have a profound effect on dose distributions for proton therapy. Although analytical calculations in homogeneous media are relatively straightforward, the modelling of the propagation of the beam through density heterogeneities can be more problematical.
Tourovsky, A. +3 more
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Secondary neutron dose during proton therapy using spot scanning
International Journal of Radiation Oncology*Biology*Physics, 2002During proton radiotherapy, secondary neutrons are produced by nuclear interactions in the material in the beam line before and after entering the patient. The dose equivalent deposited by these neutrons is usually not considered in routine treatment planning.
U. SCHNEIDER +3 more
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Defocus ramp correction in spot-scan imaging
Proceedings, annual meeting, Electron Microscopy Society of America, 1992Three-dimensional structures of a number of samples have been determined by electron crystallography. The procedures used in this work include recording images of fairly large areas of a specimen at high tilt angles. There is then a large defocus ramp across the image, and parts of the image are far out of focus.
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Spot Scan Imaging and the Future of High Resolution
Proceedings, annual meeting, Electron Microscopy Society of America, 1990Electron crystallographers who have been working on determination of protein structure have set a goal of obtaining image information to a resolution of about 3.5 Å, from specimens tilted up to 60 degrees. This information would allow the construction of a three-dimensional density map within which the path of the peptide chain could be followed and ...
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Automatic focus correction for spot-scan imaging of tilted specimens
Ultramicroscopy, 1992The variation in defocus within an image of a highly tilted specimen can be a serious source of artifact. Spot-scan imaging can be combined with dynamic focusing to greatly reduce this range of defocus. A protocol is described for determining the parameters required for the automatic focus compensation during the recording of a spot-scan image.
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