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:
Sep. 07, 1982
Filed:
Aug. 07, 1980
Frank Ainscow, Hampshire, GB;
International Business Machines Corporation, Armonk, NY (US);
Abstract
Multibeam cathode ray tube apparatus incorporates control circuits for maintaining the relative intensity of the beams over a range of settings of the brightness control. As applied to a three beam color tube, at least two, and preferably all three, of the electron guns have each a control circuit located between the control grid (V.sub.gl) and a variable voltage source (V) which constitutes the brightness control of the display. A potentiometer (R.sub.1) allows the voltage (V) to be variably attenuated and a second potentiometer (R.sub.2) acting in conjunction with a current source (I) allows the attenuated voltage to have a variable voltage added thereto. The potentiometers (R.sub.1 and R.sub.2) for each electron gun are adjusted to bring the brightness versus control voltage characteristic for each gun into coincidence. The current source (I) may be constituted by a fixed resistor and a fixed voltage. The invention is also applicable to multibeam monochrome tubes.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile