METHOD AND APPARATUS FOR CONTROLLING ELECTRON BEAM CURRENT

摘要

Methods and apparatus for independent control of electron emission current and x-ray energy in x-ray tubes are provided. The independent control can be accomplished by adjusting the distance between the cathode and anode. The independent control can also be accomplished by adjusting the temperature of the cathode. The independent control can also be accomplished by optical excitation of the cathode. The cathode can include field emissive materials such as carbon nanotubes.