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:
May. 03, 1988
Filed:
Jul. 20, 1987
David A New, Manheim Township, Lancaster County, PA (US);
RCA Corporation, Princeton, NJ (US);
Abstract
The present invention provides an improvement in color picture tubes. Such tubes include an electron gun for generating and directing three inline electron beams, a center beam and two side beams, along initially coplanar paths toward a screen of the tube. The gun includes a plurality of spaced electrodes which form a main focus lens for focusing the electron beams. The improvement comprises the plurality of spaced electrodes which form a main focus lens including three electrodes that form an einzel lens in the path of each electron beam. A first einzel lens electrode includes a first portion having three inline apertures that are set back from a second portion forming a single large aperture through which all three electron beams pass. A second einzel lens electrode includes a first portion having three inline apertures that are set back from a second portion forming a single large aperture through which all three electron beams pass. The second portion of the first einzel lens electrode faces the second portion of the second einzel lens electrode. A second einzel lens electrode also includes a third portion having three inline apertures that are set back from a fourth portion forming a single large aperture through which all three electron beams pass. A third einzel lens electrode includes a first portion having three inline apertures set back from a second portion forming a single large aperture through which all three electron beams pass. The fourth portion of the second einzel lens electrode faces the second portion of the third einzel lens electrode.