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:
Oct. 12, 1982
Filed:
Nov. 13, 1980
Richard H Burns, North Hollywood, CA (US);
Michael R Smith, Thousand Oaks, CA (US);
Irving J Bell, Canoga Park, CA (US);
Kenneth Crabtree, Saugus, CA (US);
Abstract
Graphic data entry in an interactive graphic display system is achieved by means of an apparatus that provides automatic centering of a pointing laser beam on a hand held cursor. The graphic display system provides a means for displaying and comparing through superposition full size overlaid graphical data and projected graphical data on a common display screen. It includes a steerable pointing laser the beam of which scans the display screen in response to a laser beam deflection circuit. The system also includes laser beam position sensing and indicating circuits which accurately measure the laser beam position. Centering of the laser beam on the cursor at the display screen is accomplished by dithering the beam uniformly about its average position in a discrete dither pattern and utilizing the dither pattern to determine misalignment of the beam's average position with respect to the center of the cursor. The cursor includes photo detector elements that are geometrically configured to conform to the dither pattern so that signals derived from an eccentric relationship of the beam dither pattern and the photo detector element configuration can be processed to provide beam misalignment direction and magnitude error signals. These error signals drive a servo system that centers the average beam position on the cursor. The function of the cursor is to manually or automatically measure the coordinator of graphical features on the display screen.