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. 25, 1993
Filed:
Oct. 09, 1991
Martin Gersten, New York, NY (US);
Abstract
Method for accurately displaying the location of the pupil perimeter on a corneal topography map such as is disclosed in the prior art Gersten et al., U.S. Pat. No. 4,863,260. In the process of deriving such topographic information, the process disclosed in that patent obtained a two-dimensional video image of the cornea. In the method of the present invention, the background illumination of the video image is sampled and the video signal is corrected for the effects of camera distortions, artifacts, and specular glare. The corrected data is analyzed and the point at which the greatest rate of change in background illumination occurs is determined to be a point on the periphery of the pupil. The peripheral points so determined are then displayed in superposition to the corneal topographic map thereby indicating the pupil outline.