Operation of multi-beam compact tomosynthesis system using carbon nanotube emitters

Abstract

A multi-beam compact tomosynthesis system has been developed to acquire chest X-ray images and provide reconstructed 3D X-ray images. The system uses 43 field emission X-ray sources based on carbon nanotubes (CNTs). The CNT-based X-ray source consists of an anode array, gate array, and electron gun (e-gun) array and is stationary while the digital X-ray detector moves. To analyze 3D data of the electron emission trajectory in the multi-beam X-ray source, simulation software which is CST Particle Tracking Studio was used. In this developed system, we applied a vacuum external projection type X-ray source device. Specifically, it relates to a vacuum externally protruding type X-ray source device that can be easily replaced by protruding the lower part of the unit X-ray source to the outside of the vacuum. In this study, we have developed the digital tomosynthesis system which is an improvement over conventional tomosynthesis systems as it is lighter, is easier to load the CNT e-gun, eliminates motion blur since the gantry is fixed, and provides fast and high-resolution images because of the reduction of the focal spot size with the use of multiple CNT-based X-ray sources.

Nanoparticle Filler Effect on Enhanced Field Electron Emission Properties of Carbon Nanotube Paste Emitters

“…Carbon nanotubes (CNTs) have been studied as field electron emission material due to their high aspect ratio, excellent electrical and thermal conductivity, and good mechanical strength. − There have been diverse reports on field electron emitters made with CNTs and field electron emission devices fabricated using CNT emitters such as a backlight unit, electron beam sources, microwave amplifier, and cold cathode X-ray tubes. − CNT field electron emitters have been fabricated using several methods such as as-grown CNT, CNT paste, CNT yarn, and CNT film. − CNT paste emitters using the screen-printing technique have been widely used among various fabrication methods for CNT field emitters due to the strong adhesion to substrates, good emission stability, and a simple fabrication process. ,, The screen-printed CNT paste emitters consist of CNTs, fillers, and binder material. By the way, it is noteworthy that nanoparticle fillers largely influence the field electron emission properties of the CNT paste emitter by dispersing CNTs within the CNT paste emitter, , by increasing the electrical conductivity of the CNT paste emitter, , and by enhancing the mechanical adhesion and the electrical contact between the CNT paste emitter and the cathode substrate. , …”