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. 22, 1984
Filed:
Mar. 30, 1981
Ronald G Reed, Colorado Springs, CO (US);
Robin R Schmuckal, Colorado Springs, CO (US);
Robert K McCullough, Colorado Springs, CO (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
The magnitude of a DC high voltage supplied to an internal element of a CRT is varied by a thermionic valve that is located within the envelope of the CRT and that forms a voltage divider with an external load resistor. Only a small scale signal referenced near ground is needed to produce a several thousand volt change in the high voltage supplied to the internal CRT element. The variable high voltage may control a variable deflection factor, variable spot size, or in the case of a beam penetration CRT, either variable persistence or variable trace color. In a particular beam penetration color CRT having a split anode the thermionic valve comprises a tetrode flood gun coupled by an electron mirror to a plate region in the neck of the CRT.