Broad beam electron gun: an experimental approach

Electron curtain accelerator is a type of low-energy electron accelerator, which plays an important role in many different industries such as printing, coating and packing to promote product quality, while reducing volatile organic compounds for protecting global environment. Electron emitter is one of the main components of this type of accelerators. Multi-filament cathodes and grid structures within filament housing have been designed carefully to generate uniform broad beam distribution. Compared to single filament cathode, multi-filament cathodes are more preferred in width expansion and beam uniformity. Distortion of linear filament due to thermal expansion is one of the major problems in this type of electron source. The aim of this study is to design and fabricate an appropriate mechanical system to maintain the filament in its initial shape and position when heating. In addition, dependence of emitted electrons on anode voltage (at constant cathode temperature), as well as dependence of emitted electrons on filament current (at constant anode voltage) have been experimentally investigated.