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Focal Spot Coincidence Improvement in X-ray Tubes Disclosure Number: IPCOM000012172D
Publication Date: 2003-Apr-15

Publishing Venue

The Prior Art Database


Third Generation CT Scanners routinely use the quarter ray offset in order to improve resolution. In this method, the x-ray tube focal spot is placed ¼ of the detector spacing away from the central ray. One of the important paramters in this method is the spacing between the two focal spots. This is maintained by developing fixtures that control the spacing between the anode and the cathode during construction of the insert. The position of the cathode along the anode cathode axis can be controlled during operation of the system by servos that control the pressure on that portion of the tube acting as a spring. The desired position of the cathode can be established by using the z-position detectors on the CT systems. Another possibility of controlling coincidence during manufacture is to replace the springy section of the insert with one that can yield and maintain its spacing.