An electron optical system for sheet beam vacuum electron devices

In this study we report on a development of electron optical systems including electron gun, focus system and depressed collector for sheet beam vacuum electron devices (VED). To support the requirement of the electron-wave interaction, we aim to produce a beam with current density of approximate 200A/cm
²
and an aspect ratio of 6:1. A PCM magnet stack is used for the focusing of the beam in the slow wave structure. A multistage depressed collector dedicated to sheet beam device is proposed, which is expected to aim a higher collector efficiency and better thermal distribution relative to conventional ones.