Patent Number: 6,310,938

Title: Methods and apparatus for calibrating CT x-ray beam tracking loop

Abstract: The present invention is, in one embodiment, a method for determining tracking control parameters for positioning an x-ray beam of a computed tomography imaging system having a movable collimator positionable in steps and a detector array including a plurality of rows of detector elements. The method includes steps of obtaining detector samples at a series of collimator step positions while determining a position of a focal spot of the x-ray beam; determining a beam position for each detector element at each collimator step utilizing the determined focal spot positions, a nominal focal spot length, and geometric parameters of the x-ray beam, collimator, and detector array; and determining a calibration parameter utilizing information so obtained. For example, in determining a target beam position at which to maintain the x-ray beam, a detector element differential error is determined according to ratios of successive collimator step positions; and a target beam position is selected for an isocenter element in accordance with the determined element differential errors.

Inventors: Toth; Thomas L. (Brookfield, WI), Seidenschnur; George E. (Waukesha, WI), Bromberg; Neil B. (Milwaukee, WI)

Assignee: General Electric Company

International Classification: G01N 23/02 (20060101); G01N 23/04 (20060101); G21K 001/00 ()

Expiration Date: 10/30/2018