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. 23, 1990
Filed:
Feb. 14, 1989
William D Richards, Medway, MA (US);
Other;
Abstract
A keratometer designed to be attached to a conventional ophthalimic surgical microscope for use in measuring the power and angle of orientation of an astigmatism of the cornea of an eye. The keratometer comprises an illuminator assembly for reflecting a portion of the coaxial illumination of the microscope so as to generate an annulus of light have radii of curvature identical to the radii of curvature of the cornea. A comparator assembly is also provided for reflecting and modifying a second portion of the coaxial illumination of the microscope so as to generate at least one spherical second annulus of light. The keratometer is arranged to superimpose the second annulus on the first annulus and to cause said superimposed annuli to pass into the objective lenses of the microscope whereby the radius of curvature of the cornea may be determined. Also included is a protractor ring for use in measuring the angle of orientation of the astigmatism. No optical lenses or light sources ae included in the keratometer.