Title :
Characterization of multi-beam cathode using thermionic emission microscope
Author :
Shukla, Sushil K. ; Ruddarraju, Suryanarayana R. ; Prajesh, Rahul ; Rajoriya, Niharika
Author_Institution :
Rajasthan, Microwave Tubes Div., Banasthali Univ., Pilani, India
Abstract :
Thermionic emission microscope (THEM) is an analytical research tool to study the emission uniformity of a thermionic cathode. In this paper, the design of electrostatic lens for a multi-beam cathode (MBC) has been given using 2-D TRAK and Omni-TRAK codes. The design of single beam lens system, available with us, containing a small cathode has been modified to study large size MBC using scaling laws. The present MBC contains 19 protruding buttons contributing to 19 beamlets whose image is projected onto the screen for study. The influence of various parameters such as protrusion, diameter of button, and their interspacing has been studied. The studies prove that THEM could be used as an effective tool for the characterization of MBC.
Keywords :
electron microscopes; electrostatic lenses; thermionic cathodes; thermionic emission; 2D TRAK codes; THEM; electrostatic lens design; emission uniformity; large size MBC; multibeam cathode characterization; omniTRAK codes; scaling laws; single beam lens system design; thermionic cathode; thermionic emission microscope; Cathodes; Electrostatics; Lenses; Microscopy; Thermionic emission; Trajectory; 2-D TRAK; MBC; Omni-TRAK; THEM; immersion lens; scaling laws;
Conference_Titel :
Vacuum Electron Sources Conference (IVESC), 2012 IEEE Ninth International
Conference_Location :
Monterey, CA
Print_ISBN :
978-1-4673-0368-2
DOI :
10.1109/IVESC.2012.6264190
