Collector design for computed radiography

Abstract

A light collector and detector for collecting and detecting light emitted, reflected or transmitted by a scanned information medium, comprising: a planar mirror assembly for extending the width of a scanned information medium and for disposition substantially perpendicular thereto, the planar mirror assembly having a lower edge adjacent to the scanned medium and an upper edge spaced from the lower edge; first and second pyramidal mirrors located side by side facing the planar mirror, the pyramidal mirrors having respective upper edges spaced from the upper edge of the planar mirror and respective lower edges spaced from the lower edge of the planar mirror, thereby to form aligned slots for the passage of a scanning beam of light to a medium to be scanned and for allowing light emitted by, reflected from, or transmitted by the scanned medium to enter the collector; wherein the first pyramidal mirror has a first aperture in an apex region thereof and wherein the second pyramidal mirror has a second aperture in an apex region thereof; a first photodetector having a light receiving face coextensive with the aperture of the first pyramidal mirror; a second photodetector having a lightreceiving face coextensive with the aperture of the second pyramidal mirror; wherein light from the scanned medium and reflected by the collector mirrors are received by the light receiving faces of the first and second photodetectors which generate electrical signals in response thereto.