X-ray position measuring and calibration device

Abstract

A calibration system having a radiation source that generates the beam of radiation along the angular directions .theta., .phi.. A first reference element which is separated from the radiation source by a distance of approximately Z.sub.1 is then exposed to the beam of radiation. A second reference element is also present which is separated from the first reference element by a predetermined distance H and is exposed to the beam of radiation. An image detector produces images of the first and second reference elements, wherein the images are separated from each other by a distance R and angle .phi.. The device further includes an angle measurement device that calculates .theta. from the values of Z.sub.1 and H. A position measurement device having first and second sources of radiation that generate respective first and second beams of radiation directed at angles .theta..sub.1, .phi..sub.1, and .theta..sub.2, .phi..sub.2 respectively, toward an object of interest. An image detector is provided for producing 1) a first image of the object of interest formed by the first beam of radiation and 2) a second image of the object of interest formed by the second beam of radiation and that is separated from the first image by a distance L. A coordinate device then determines the coordinate of the object of interest from the values of .theta..sub.1, .theta..sub.2 and L.