A Lanthanum Hexaboride cathode manufactured by Kimball Physics, Inc.
Permission has been given by my employer, Kimball Physics, Inc. to provide this image for anyone to use for any purpose as long as Kimball Physics, Inc. is credited for the image.
The original uploader was <a href="https://en.wikipedia.org/wiki/User:Ahecht" class="extiw" title="wikipedia:User:Ahecht">Ahecht</a> at <a href="https://en.wikipedia.org/wiki/" class="extiw" title="wikipedia:">English Wikipedia</a>.
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