Multi-Beam X-ray Source with Seven Focal Spots Based on Field Emission of Carbon Nanotubes Cathode

A novel type of the multi-beam X-ray source, comprising seven discrete cathodes made of carbon nanotubes (CNTs) array and properly aligned, has been successfully developed, which has the characteristics of multi-beam integration and programmable pulse emission.The nanostructures of the self-assembled CNTs array cathode were characterized with scanning/transmission electron microscopy.Radiation imaging system, based on the newly-developed X-ray source, can quickly achieve seven different views on stationary tomo-synthesis imaging.The simulated test results show that under the favorable conditions, the maximum current, stably emitted from a single CNTs cathode, was be up to 14 mA.The optimized X-ray source structure, designed by numerical simulation, is capable of effectively and consistently focusing electron beam to an average size of 0.6 mm×0.95 mm at an anode voltage of 70 kV.Moreover, ultra-high vacuum (UHV) degassing and high precision packaging ensured the required UHV environment of the multi-beam X-ray source.