Earliest possible detection of breast carcinoma requires exceptional spatial resolution and contrast sensitivity, which are of prime importance for the visualization of fine detail on mammographic images, particularly if captured digitally. Image quality depends greatly on the following technical improvements: minimized off-focus X-rays, shorter exposure time, smaller, crisper and variable focal spots, and optimized X-ray spectrum. Current X-ray tube technology is close to its limits. A more radical change in tube design is proposed here to improve image quality by transferring and adapting advanced technologies found in other fields to X-ray tube design: (a) metal-ceramic oil-free construction, (b) advanced rotor dynamics allowing ultra fast rotation, (c) advanced cathode technology based on novel electron emitters and computer synthesized gun technology, (d) multi-element target together with electron beam deflection capability. A three step approach is proposed: (1) Develop super compact metal- ceramic, oil-free X-ray tube with conventional cathode. PURPOSE: field compatible tube with negligible off-focus X-rays (part of Phase I efforts); (2) Extend development to include new cathode technology and higher power levels. PURPOSE: superior focal spots, exposure time reduction; (3) Develop ultra fast rotor. PURPOSE: greatly increased power levels in conjunction with high density electron beams, to minimize exposure time and focal spot size for better resolution.
Greatly improved performance of mammography tubes will make them the preferred choice for new machines (U.S. market: 2,000/yr.) as well as for replacements (U.S. installed base: 11,000, 1 tube per 2 years: total 5,500 tubes/yr.). The compact version of the tube allows for simpler and less expensive manufacturing.
