Electrostatic fields in ionography.

D Plewes; H E Johns

doi:10.1118/1.594167

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PubMed · 1186618

Electrostatic fields in ionography.

D Plewes·H E Johns

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Abstract

There is renewed interest in diagnostic radiology in electrostatic methods of imaging, such as xeroradiography and ionography. This is due to the fact that edge contrast can be achieved, aiding in the visualization of soft tissue tumors. In analyzing the image forming properties of these system, we chose to solve the electrostatic problems by the method of images. We present methods and recursion formulas for calculating electrostatic fields due to (a) any charge distribution on a slab of dielectric (the solution involves a single infinite series) or (b) the same as the above with the introduction of an additional ground plane parallel to the dielectric surface (the solution now involves double infinite series). Analysis of these fields suggests new methods of controlling edge contrast and development configurations where the field which penetrates through the foil is used to produce the final image rather than the field above the charged surface.

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D Plewes, H E Johns. Electrostatic fields in ionography.. https://doi.org/10.1118/1.594167

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