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:
Apr. 07, 1992
Filed:
Sep. 12, 1991
Kenjiro Katsuragi, Tokyo, JP;
Kabushiki Kaisha Topcon, Tokyo, JP;
Abstract
A noncontact type tonometer has a nozzle for discharging fluid toward an eye to be tested, an alignment target projecting optical system for projecting an alignment target light used for aligning the eye and an apparatus body toward the center of curvature of the cornea of the eye from the axial direction of said nozzle while converging the same thereto by an objective lens and forming a virtual image at the center of curvature of the cornea, and an alignment light receiving optical system for reimaging the virtual image on a light receiving portion as a target image. The improvement is characterized in that the alignment light receiving optical system is provided with a light splitter adapted to split an alignment target light for forming the virtual image based on specular reflection of the cornea and guiding the same to the light receiving portion in order to verify the alignment with reference to coincidence or noncoincidence of the alignment target image.