Patent ID: 9093245
Filing Date: 2015-07-28
Classification: H01J,H05G

Abstract:
1. An electron source for an X-ray scanner comprising an emitter support block having a first side and a second side; an electron-emitting region formed on the emitter support block and arranged to emit electrons; an electrical connector arranged to connect a source of electric current to the electron-emitting region; at least one focusing element arranged to focus the electrons towards an anode and having a lower portion extending parallel to said first or second side and a curved upper portion extending upward from the lower portion, beyond the electron-emitting region, and curving back toward the electron-emitting region; an extraction grid between said emitter support block and the at least one focusing element, wherein the at least one focusing element is held at an electrical potential that is negative with respect to the extraction grid; and heating means arranged to heat the support block.