In this space, visitors are invited to post any comments, questions, or skeptical observations about Philo T. Farnsworth's contributions to the field of Nuclear Fusion research.
Subject: Re: Thermionic Ion Source Grid
Date: Aug 03, 09:12 am
Poster: Richard Hull
On Aug 03, 09:12 am, Richard Hull wrote:
>The Hirsch/Meeks patent shows a thermionic cathode (#29) in conjunction with the ion source grid (#22). If the ion source grid were also thermionic would this improve the performance of the grid? Or would the grid better serve if it could somehow be cooled?
No, The ion grid is best to just act as a collector of electrons. Remember that we, ideally, do not want electrons in the intergrid region! This grid traps them to serpintine about itself. The electrons create ions which then blast inward to the central grid.
If the ionizer grid were thermionic, the electron energies would be too low to be effective ionizers. The cathode electrons are also not good ionizers until they accelerate towards the ionizer grid and bump into deuterium atoms.