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:
Sep. 14, 1999
Filed:
Jan. 21, 1998
Neil Anthony Fox, Cheltenham, GB;
Wang Nang Wang, Lympley Stoke, GB;
Smiths Industries Public Limited Company, London, GB;
Abstract
An electron emitter (2) has a semiconductor substrate (20) doped with an n-type region (21). A diamond layer (24) is doped by ion implantation with a p-type dopant to form a graded dopant profile region (27) that increases away from the upper surface of the diamond layer (24) and a thin insulating region (28) separating the p-type region (27) from the n-type region (21). The emitter (2) has a first electrical contact (23) on a lower surface of the substrate (20) and a second electrical contact (25) on the upper surface of the diamond layer (24) such that a voltage can be applied across the emitter (2) to cause tunneling of electrons from the n-type region (21) through the insulating region (28) into the p-type region (27), causing emission of electrons from an exposed surface (29). A lamp or display (1) includes several such electron emitters (2) and contains gas at reduced pressure, which is ionized by the emitted electrons, thereby generating UV radiation, which causes a fluorescent layer (5) on a transparent window (3) to produce visible light.