Study on the Influence of Control Grid on the Emission Characteristics of Cathode Assembly

Low-energy electron curtain accelerators are widely used in the field of radiation processing. In this paper, the model of the cathode emission assembly of the multi-filament electron curtain accelerator is established by CST simulation software, and the influence of the duty ratio and grid width of the semi-cylindrical control grid on the current emission characteristics of the cathode assembly is explored. It is found that the larger the duty ratio of the control grid and the wider the mesh grid width, the emission current and the current drawn at control grid increase. Especially when the width of mesh grid reaches 3mm, the current emission characteristics of the cathode assembly no longer conform to the three-half law. The research work in this paper has reference significance for the construction and design of cathode assembly.