A dramatic improvement in the lifetime of the fully vacuum-sealed micro-focusing X-ray tube for stationary digital breast tomosynthesis

We have successfully fabricated the reliable vacuum-sealed X-ray tube with carbon nanotube (CNT) emitters through a specially designed brazing process. The robust CNT emitters were also adopted for high-temperature endurance during the brazing process. The stable field emission current from the sealed X-ray tube indicated a good maintenance of vacuum level needed for the CNT field emitters. The stability and reliability of the vacuum-sealed X-ray tube could be further improved by the active-current control unit having a wide saturation range for a constant current.