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:
Feb. 01, 2000
Filed:
Apr. 24, 1998
Asahi Kogaku Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A real-image finder comprises an objective optical system which forms an image of an object to be viewed; a field frame member located on a primary image forming plane on which the image formed by the objective optical system is formed; an ocular optical system through which the object image formed on the primary image forming plane; and an image erecting optical system which erects the object image formed by the objective optical system. The transparent members are provided on the front and rear surfaces of the field frame, and the thickness of the transparent members are determined so that if a foreign matter sticks to the end surfaces of the transparent members that are opposite to and located away from the field frame member, no foreign matter can be viewed through the ocular optical system.