Kinestatic charge detection using synchronous displacement of detecting

Abstract

A technique for detecting the spatial distribution of propagating energy induces secondary energy produced in a detector to drift in a predetermined direction at a predetermined velocity and synchronously moves the detector in a direction opposite to the direction of drift of the secondary energy at a velocity equal in magnitude to the magnitude of the velocity of drift of the secondary energy. Although the secondary energy is drifting with respect to the detector, the synchronous detector movement causes the secondary energy to appear stationary with respect to a source of radiation, resulting in 'kinestatis' of the secondary energy. The secondary energy resulting from the radiation integrates along stationary paths in the detector (operated as a 'kinestatic detector') and is subsequently detected when a collection volume of the detector sweeps through the stationary secondary energy. Signal integration can occur over long periods of time while resolution in the direction of movement of the detector is determined by the detector output sampling rate. A detector having n-by-l detecting elements can simulate the operation of an n-by-m element detector for use in digital radiography and computed tomography and other imaging and non-imaging sensing techniques. The detector may take the form of a xenon gas ionization chamber. Field distortion eliminating techniques are used to eliminate variations in charge carrier drift velocity in such an ionization chamber. Charge carrier mobility and drift velocity are adjusted to synchronize charge carrier movement with detector movement.