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:
Nov. 03, 1987
Filed:
Dec. 02, 1985
John L Addis, Beaverton, OR (US);
David W Morgan, Gaston, OR (US);
Tektronix, Inc., Beaverton, OR (US);
Abstract
A beam detection apparatus for sensing the position of an electron beam within a cathode ray tube is disclosed. The apparatus includes a photodetector for optically detecting the intersections of the electron beam with a graticule line on the faceplate of the cathode ray tube. In a second embodiment, an electrically conductive pattern of reference markers is applied to the graticule for intercepting the beam and a detector is coupled to the conductive pattern for detecting the interception. Calibration circuitry is also included to generate input signals to deflection amplifiers coupled to the cathode ray tube and to evaluate detection signals generated by the beam coinciding with a graticule line. The calibration circuitry compares the input signals to the input signal value represented by the graticule line and adjusts the deflection amplifiers of the cathode ray tube accordingly to cause the beam to coincide with a graticule line bearing a predetermined relationship to the input signal deflecting the beam.