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:
Oct. 28, 2008
Filed:
Sep. 28, 2005
Michael W. Geis, Acton, MA (US);
Theodore H. Fedynyshyn, Sudbury, MA (US);
Sandra J. Deneault, Waltham, MA (US);
Keith E. Krohn, Chelmsford, MA (US);
Theodore M. Lyszczarz, Concord, MA (US);
Michael F. Marchant, N. Chelmsford, MA (US);
Michael W. Geis, Acton, MA (US);
Theodore H. Fedynyshyn, Sudbury, MA (US);
Sandra J. Deneault, Waltham, MA (US);
Keith E. Krohn, Chelmsford, MA (US);
Theodore M. Lyszczarz, Concord, MA (US);
Michael F. Marchant, N. Chelmsford, MA (US);
The Massachusetts Institute of Technology, Cambridge, MA (US);
Abstract
A surface-emission cathode formed on an insulating surface having cantilevered, i.e. 'undercut,' electrodes. Suitable insulating surfaces include negative electron affinity (NEA) insulators such as glass or diamond. The cathode can operate in a comprised vacuum (e.g., 10Torr) with no bias on the electrodes and low vacuum electric fields (e.g., at least 10 V cm). Embodiments of the present invention are inexpensive to fabricate, requiring lithographic resolution of approximately 10 micrometers. These cathodes can be formed over large areas for use in lighting and displays and are suitable for satellite applications, such as cathodes for tethers, thrusters and space-charging neutralizers.