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:
Aug. 25, 1992
Filed:
May. 30, 1991
Akihiro Arai, Tokyo, JP;
Hideki Hatanaka, Tokyo, JP;
Akihiko Sekine, Tokyo, JP;
Isao Minegishi, Tokyo, JP;
Fumio Ohtomo, Tokyo, JP;
Kabushiki Kaisha Topcon, Tokyo, JP;
Abstract
An intraocular length measuring instrument including a light source having a short coherent length, a beam splitter for forming a measuring optical path across the interior of an eye to be tested and a reference optical path within the instrument, and guiding a beam of light from the light source to both the measuring optical path and the reference optical path, a first light receiving portion for interfering light reflected by an intraocular object to be measured after passing along the measuring optical path with light coming through the reference optical path and receiving a resultant interference light, an intraocular object position measuring portion for finding an optical path difference from an optical path length of the reference optical path and a peak position of a signal coming from the first light receiving portion, a light irradiating optical system for irradiating a light beam to the cornea of the eye to be tested, a light receiving optical system for introducing a reflected light from the cornea to a second light receiving portion, and a corneal position measuring portion for fining a position of the cornea from an output of the second light receiving portion.