X-ray tube current control with constant loop gain.

摘要

The tube current (IT) in an x-ray tube (10) is controlled by a closed loop control circuit (30,51,54,25,27,21,52,10) in which a tube current feedback signal is used to control x-ray tube filament current. The gain of the feedback loop is maintained substantially constant over a wide range of tube currents by the inclusion of a multiplier (51) by which is inserted into the loop a signal (on 52) proportional to the reciprocal of the tube current command.