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. 06, 1984
Filed:
Jun. 03, 1981
Kazuo Nunokawa, Itabashi, JP;
Abstract
An eye fundus camera is disclosed having a working distance detecting device. The eye fundus camera includes an illuminating system having a ring-shaped aperture through which the illuminating light beam is projected to the eye to be examined through an objective lens. The working distance detecting device includes an opaque portion formed in said ring-shaped aperture and having a width in circumferential direction. A light receiving portion is provided around the objective lens at a position corresponding to the opaque portion in the image of the ring-shaped aperture formed by beams of the illuminating light reflected from the cornea of the eye so that the working distance can be detected based on the width of the opaque portion of the image of the ring-shaped aperture.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile