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:
Jan. 13, 1998
Filed:
Nov. 28, 1995
Hiroshi Iijima, Tokyo, JP;
Akinari Takagi, Tokyo, JP;
Kabushiki Kaisha Topcon, Tokyo, JP;
Abstract
An ophthalmological instrument is provided in which optical members can be satisfactorily cleaned, the times for cleaning can be reduced and reliability of measuring accuracy can be improved. An alignment between a cornea (C) of an eye (E) to be tested and an instrument body is detected by projecting an alignment detecting light toward the cornea (C) through alignment detecting optical systems (30, 40) and receiving a luminous flux reflected on the cornea (C) through a light receiving sensor (45). A working distance between the cornea (C) and the instrument body is detected projecting a working distance detecting light toward the cornea (C) through working distance detecting optical systems (50, 60) and receiving a luminous flux reflected on the cornea (C) by a light receiving sensor (63). Part of optical paths of the alignment detecting optical systems (30, 40) and the working distance detecting optical systems (50, 60) are not used in common. Dirt stuck to optical members arranged in part of the optical paths which are used in common is detected in accordance with signals from the light receiving sensors (45, 63).