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:
Jun. 17, 1997
Filed:
May. 15, 1996
Nihon Kohden Corporation, Tokyo, JP;
Abstract
A housing has a hollow section, and openings are formed at both ends of the hollow section so as to communicate with the outside. An aperture is formed in the internal wall of the housing so as to oppose the opening, and a video camera is fitted into the opening. A half mirror, a mirror, an optical lens, and light sources are disposed within the hollow section. The light sources are alternately illuminated while a patient wears equipment having such a construction. Light reflected from one eye passes through the half mirror and enters a light receiving surface of the video camera. On the other hand, light reflected from the other eye is reflected from the mirror and a half mirror and, then, enters the light receiving surface of the video camera. The optical lens corrects an error arising from a difference in length between two optical paths.