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:
Mar. 09, 2004
Filed:
Sep. 28, 2000
Nijs Cornelis Van Der Vaart, Eindhoven, NL;
Gerardus Gegorius Petrus Van Gorkom, Eindhoven, NL;
Petrus Hubertus Franciscus Trompenaars, Eindhoven, NL;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
A cathode ray tube comprising an electron source and an electron beam guidance cavity having an input aperture and an output aperture, wherein at least a part of the wall of the electron beam guidance cavity near the output aperture comprises an insulating material having a secondary emission coefficient &dgr; for cooperation with the cathode. Furthermore, the cathode ray tube comprises a first electrode which is connectable to a first power supply for applying, in operation, an electric field with a first field strength E between the cathode and the output aperture. &dgr; and E have values which allow electron transport through the electron beam guidance cavity. The cathode ray tube further comprises a conventional main lens to obtain a spot on a display screen. According to the invention, an electron lens is placed between the exit of the cavity and the main lens for directing the electron beam at a predetermined angle towards the entrance of the main lens.