Digital radiography detector resolution improvement

Abstract

A digital radiographic system and method is disclosed having improved detector resolution. The system includes an X-ray source and a spaced detector assembly having several staggered columns of uniform square detector elements. The detector elements are thus arranged in interspersed rows with the center-to-center spacing between successive members of each row being about twice the lateral dimension of each square element. In response to incident X-radiation, each detector element produces an electrical charge signal indicative of the radiation. Power means actuates the source to propagate X-ray energy in a beam along a path toward the detector assembly, in which path a subject may be interposed for examination. Mechanism is provided for scanning the detector assembly, synchronously and in alignment with the X-ray beam, relative to a subject. The relative scanning motion is perpendicular to the columns of detector elements. Time delay and integrate circuitry is provided, separate from but coupled to the detector elements. Detector element electrical signals are sampled at successive increments of scanning motion equal to half the width of a detector element. Respective delay circuitry built into the time delay and integrate circuitry delays element output signals differently as a function of detector element spacing and sampling frequency, in order to superimpose data for each respective image pixel and to present all signals relating to each respective pixel simultaneously to a summing output for imaging.