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. 24, 1999
Filed:
May. 21, 1997
Neil Alexander Cade, Herts, GB;
GEC-Marconi Limited, , GB;
Abstract
An electron field emission device includes a field emissive cathode which may include a plurality of sharp field emitter tips 2. First and second grids 4 and 7 are located between the cathode and an anode. The grids comprise parallel strips of electrically conductive material, those of the first grid being arranged orthogonal to those of the second. Applications of suitable voltages to the grids enable selected regions of the cathode to be made electron emissive and produce collimated electron beams. The anode may be phosphor coated to produce a visible display or an infra-red image may be produced. Relatively low voltages may be used to switch the regions on and off. As the beams are collimated, the anode may be located a relatively large distance from the cathode, enabling high voltage phosphors to be used.