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:
Mar. 16, 1993
Filed:
Jun. 03, 1991
Applicant:
Inventor:
Carl M Penney, Saratoga Springs, NY (US);
Assignee:
General Electric Company, Schenectady, NY (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
A61B / ; G03H / ;
U.S. Cl.
CPC ...
351212 ; 351221 ; 351246 ; 359-1 ; 359 19 ;
Abstract
A hologram is used to project an image of a pattern similar to a placido upon the cornea of a subject. By viewing the reflection of the pattern in the subject's cornea, one may measure the curvature of the cornea. The use of the hologram in the keratometer system allows the pattern to be imaged at infinity, thereby minimizing any error which might otherwise result from incorrect assumptions about the cornea position.