The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 18, 1998
Filed:
May. 01, 1996
John Edwin Graebner, Short Hills, NJ (US);
Sungho Jin, Millington, NJ (US);
Gregory Peter Kochanski, Dunellen, NJ (US);
Wei Zhu, Middlesex, NJ (US);
Lucent Technologies, Inc., Murray Hill, NJ (US);
Abstract
In accordance with the invention, a microwave vacuum tube device, such as a traveling wave tube, is provided with an electron source comprising activated ultrafine diamonds. Applicants have discovered that ultrafine diamonds (5-1,000 nm diameter), when activated by heat treatment in a hydrogen plasma, become excellent room-temperature electron emitters capable of producing electron emission current density of at least 10 mA/cm.sup.2 at low electric fields of 10 V/micrometer. Sources using these diamonds provide electrons for microwave vacuum tubes at low voltage, low operating temperature and with fast turn-on characteristics. A multiple grid structure is described for providing high quality electron beams particularly useful for traveling wave tubes.