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:
Dec. 31, 1991
Filed:
Feb. 11, 1991
Conrad J Odenthal, Portland, OR (US);
Tektronix, Inc., Beaverton, OR (US);
Abstract
A cathode-ray tube (10) includes a prefocusing lens (14) and an adjacent high-voltage einzel focus lens (16) to form an electron beam with low spherical aberration. The high-voltage einzel focus lens includes a central lens element (52) positioned between a pair of outer lens elements (54) and (56). The outer lens elements receive a common high-voltage potential of more than about 12 kilovolts. The prefocusing lens includes a G3 electrode positioned between an anode (48) and a first one of the outer lens elements of the einzel focus lens. The G3 electrode receives the high voltage applied to the outer lens elements. In a preferred embodiment, the G3 electrode is a flat end disc plate (57b) on the end of the first one of the outer lens elements.