Patent ID: 8284899

Claim:
An x-ray tube suitable for use in a mammography imaging procedure, the x-ray tube comprising: an evacuated enclosure having a first end and a second end interconnected by a side wall; a bearing assembly; an anode rotatably supported by the bearing assembly within the evacuated enclosure the anode having a top side and a bottom side and configured to have a predefined size, shape and electrical potential, the anode including: a target surface disposed on the bottom side and having a radially sloped annular focal track adjacent an outer periphery of the target surface, the target surface facing and axially offset from the bearing assembly; and a second surface formed on the top side of the anode opposite from the target surface and facing the first end of the evacuated enclosure; and a cathode assembly, the cathode assembly including a support structure to retain an electron emitter that is axially aligned with a focal spot area on the focal track, wherein the electron emitter is positioned within the evacuated enclosure so as to emit electrons for impingement on the focal spot area; and an x-ray window defined in the side wall, wherein a distance H defines the distance between the focal spot area and the first end, and wherein the size, shape and electrical potential of the anode are selected so as to reduce the distance H, and substantially no intervening structure is positioned between the first end of the evacuated enclosure and the second surface of the anode so as to reduce the distance H.