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. 23, 1999
Filed:
Apr. 04, 1997
Thomas R Rohlfing, Salt Lake City, UT (US);
Evans & Sutherland Computer Corporation, Salt Lake City, UT (US);
Abstract
A method and apparatus for performing a lens calibration procedure which is executed for each camera and lens pair. The calibration procedure is performed to determine the camera and lens nodal point offset and field of view, plus image offset in both the horizontal and vertical directions as a function of lens zoom and focus settings. The method includes the step of providing apparatus which enables the semi-automatic and rapid entry of data points representing lens zoom and focus setting information, thereby eliminating a source of human error. The general method includes the steps of creating a real environment and an identical virtual environment which is a copy of the real environment. The image from the virtual environment is superimposed on a monitor displaying the real environment. The camera's zoom and focus rings are incremented through a plurality of values by discrete steps. For each value, the virtual environment's settings are manipulated until the real and virtual images are identical. The values from the virtual environment are then recorded as a data point corresponding to a specific camera lens zoom and focus setting. A plurality of data points are then recorded to create the calibration dataset.