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:
Dec. 02, 1986
Filed:
Mar. 29, 1984
Susumu Takahashi, Tokyo, JP;
Kiwami Horiguchi, Tokyo, JP;
Tokyo Kagaku Kikai Kabushiki Kaisha, Tokyo, JP;
Abstract
An eyefundus camera including an observing and photographing optical system having a focusing lens, a mark projecting optical system for projecting a plurality of mark images on patient's eyefundus. The mark projecting optical system is interconnected with the focusing lens of the observing and photographing optical system. There is provided a focusing signal detecting device including a photoelectric device for photoelectrically scanning the mark images projected on the fundus of the patient's eye to produce mark image signals, a horizontal synchronizing signal counting circuit for counting horizontal synchronizing signals for the photoelectric means, a mark image counting circuit for counting number of the mark image signals to determine that a predetermined number of mark image signals exist in a single scanning line, an operation circuit responsive to outputs of the two circuits for determining a horizontal scanning line which is used for judgement of focus conditions.