| 摘要 |
In an X-ray imaging system, an arrangement is provided for readily aligning the system detector with the X-ray beam field, i.e., the projection of the X-ray beam into the plane of the detector. The arrangement is adapted for correcting or compensating for distortion which results from X-ray beam angulation, wherein the beam is projected toward the detector plane at an angle of less than 90°. Initially, the system X-ray tube is positioned to project the X-ray beam at a given beam direction angle phi. A beam width angle gamma1 is then computed, from the given angle phi and from specified values of the source-to-image distance and the length of the projected beam field. Thereupon, an offset value is determined from gamma1, phi and the source-to-image distance to locate the geometric center of the beam field, and the center of the detector is aligned therewith.
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