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. 17, 2006
Filed:
May. 20, 2004
Osamu Ono, Ibaraki, JP;
Shigeru Sugawara, Ibaraki, JP;
Toshio Shimaoogi, Ibaraki, JP;
Tomoyuki Hayama, Ibaraki, JP;
Osamu Ono, Ibaraki, JP;
Shigeru Sugawara, Ibaraki, JP;
Toshio Shimaoogi, Ibaraki, JP;
Tomoyuki Hayama, Ibaraki, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
A prefocus lens section in an electron gun assembly includes a second grid that is disposed on an electron beam generating section side, a third grid that is disposed on a main lens section side, and a shield grid that is disposed between the second grid and the third grid. The shield grid is a cup-shaped electrode with a side wall that surrounds an outer peripheral part of the third grid, which part is located on the second grid side, and extends in parallel to a tube axis. The shield grid has a bottom surface disposed to face the second grid and has an open end disposed to face the third grid. A relationship, Ec<Vf<Er, is established, where Ec is a potential applied to the second grid, Vf is a potential applied to the shield grid, and Er is a potential applied to the third grid.