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. 21, 1998
Filed:
Jan. 31, 1997
Tsuguo Nanjo, Toyohashi, JP;
Masunori Kawamura, Nagoya, JP;
Nidek Company, Ltd., , JP;
Abstract
A fundus camera for photographing fundus of an eye to be examined, comprises observing illumination/target projection optical system provided with a slit-plate having a pin-hole aperture and a ring-slit, for illuminating the eye to be examined with an illumination light bundle for use in observation that is formed by the ring-slit to be ring-shaped by illuminating the slit-plate uniformly, and for projecting an alignment index onto a cornea of the eye to be examined by using a light bundle that has passed through the pin-hole aperture, photographing illumination optical system for illuminating the eye to be examined with a ring-shaped illumination light bundle for use in photography by using a part of optical path of the observing illumination/target projection optical system, observation optical system for observing the focused condition of an image of the alignment index projected onto the cornea of the eye to be examined and the fundus of the eye to be examined by using the observing illumination/target projection optical system, and photographing optical system using a part of optical path of the observation optical system and for photographing the fundus of the eye to be examined that is illuminated with the photographing illumination optical system, whereby the suitability of the alignment is determined by observing the focused condition of the image of the alignment index by using the observation optical system.