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:
Sep. 07, 2021
Filed:
Jan. 24, 2018
Topcon Corporation, Tokyo, JP;
Toshifumi Mihashi, Tokyo, JP;
TOPCON CORPORATION, Tokyo, JP;
Abstract
Provided is an ophthalmic measurement device with which it is possible to obtain an area in which a measurement can be taken without moving an optical system. With reference to an optical path length of an illumination optical system with which light is focused on the eyeground when the refraction value is 0 D, the positions of two light sources are set to achieve a setting in which the optical path length becomes slightly shorter. By doing so, it is possible to cope with measurement of refractive properties in a large area without employing structures that allow a lens system of the illumination optical system and the light sources thereof to be moved. In addition, by selecting one of the two light sources so that a clearer Hartmann image can be obtained, it is possible to further increase the precision of the refractive properties to be measured.