Apparatus and method for improved transient response in an electromagnetically controlled X-ray tube

An x-ray tube assembly comprising:

• a housing having a vacuum formed therein, the housing comprising:
• a cathode portion;
• a target portion;
• and
• a throat portion comprising:
• a first section having a first wall thickness;
• a second section having a second wall thickness;
• and
• a first magnetic field section positioned between the first and second sections, the first magnetic field section having a third wall thickness that is thinner than the first and second wall thicknesses;
• a target positioned in the target portion of the vacuum housing;
• and
• a cathode positioned in the cathode portion of the vacuum housing to direct a stream of electrons toward the target.

An imaging system comprising:

• a rotatable gantry having an opening therein for receiving an object to be scanned;
• a table positioned within the opening of the rotatable gantry and moveable through the opening;
• an x-ray tube coupled to the rotatable gantry, the x-ray tube comprising:
• a vacuum chamber comprising:
• a target portion housing a target;
• a cathode portion housing a cathode;
• and
• a throat portion comprising:
• a first section having a first wall thickness;
• a second section having a second wall thickness;
• and
• a first magnetic field section coupled to the first and second sections, the first magnetic field section having a third wall thickness that is thinner than the first and second wall thicknesses;
• and
• a first electron manipulation coil mounted on the x-ray tube and configured to generate a first magnetic field to manipulate a stream of electrons emitted from the cathode, the first electron manipulation coil mounted on the x-ray tube and aligned with the first magnetic field section of the throat portion of the vacuum chamber such that a rise time of the first magnetic field is faster in the first magnetic field section than in the first and second sections.