Patent · US Expired

X-ray tube anode focusing by low voltage bias

US5007074A · kind A · utility

5Cited by
16References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 25, 1989
Grant dateApr 9, 1991
Priority date
Expiry dateJul 25, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J35/066
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An x-ray tube is disclosed whose cathode cup is battery biased at a low level, approximately 30 volts DC, to inhibit "wings" on the focal spot of electrons bombarding the anode. The battery for providing bias, floats at the DC electrical potential applied to the cathode, many KV below ground potential. Geometric modifications to the filament/focusing cup arrangement are also included. The geometrical characteristics partially inhibit the dispersion of electrons, inhibiting the formation of "wings" on the x-ray focal spot, particularly at high current levels. At lower current levels, the low DC battery bias enhances the anti-dispersion effects of the geometrical characteristics to inhibit wing formation even at these lower current levels.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.