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:
Jan. 23, 2001
Filed:
May. 11, 1998
John Beeteson, Ayrshire, GB;
Andrew Ramsay Knox, Ayrshire, GB;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A display device comprises a substrate, cathode means for emitting electrons, a permanent magnet and one or more supports between the substrate and the magnet. A two dimensional array of channels extends between opposite poles of the magnet, the magnet generating, in each channel, a magnetic field for forming electrons from the cathode means into an electron beam. A screen receives an electron beam from each channel, the screen having a phosphor coating facing the side of the magnet remote from the cathode, the phosphor coating comprising a plurality of pixels each corresponding to a different channel. Grid electrode means is disposed between the cathode means and the magnet for controlling flow of electrons from the cathode means into each channel, the grid electrode means having a plurality of apertures, each aperture corresponding to one of the channels. The apertures are of varying cross-section in the vicinity of the supports such that localized variations in the emission of electrons by the cathode means caused by the one or more supports is compensated. The display also has one or more spacers between the screen and the magnet and anode means disposed on the surface of the magnet remote from the cathode for accelerating electrons through the channels. The anode means is of varying shape in the vicinity of the spacers such that localized variations in the electron beam shape and position caused by the one or more spacers is compensated.