Simulation Study on Electron Focusing for the First Prototype of a Compact X-Ray Tube

摘要

For a typical computed tomography (CT) system built with a conventional CT architecture, the current mechanical limits and materials do not allow the temporal resolution to be reduced lower than ~224 msec [1]. Researchers are developing semi-stationary CT and stationary CT architectures that use a stationary array of distributed x-ray sources to eliminate the rotating parts in a gantry, either partially or completely, respectively [1]. For such an array of distributed x-ray sources, to acquire enough projections for a successful CT reconstruction (200 to 400, depending on the application and reconstruction algorithm), a closely-spaced array of individually addressable x-ray sources that are capable of producing high-frequency x-ray pulses is required. The present summary is of a study conducted as a part of a research continuum toward developing a compact x-ray tube potentially to be used in the said stationary array. Specifically, this work entails the design of an electrostatic lens for electron focusing in the first prototype of a compact x-ray tube. The first prototype of a compact x-ray tube is to use a commercially available (from HeatWave Labs, Inc.) field emission (FE) based cold-cathode with carbon nanotubes (CNTs) as emitters; a transmission type anode; and an electrostatic lens for electron focusing.