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:
May. 31, 1994
Filed:
Nov. 13, 1992
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
The automatic focusing apparatus of this invention focuses the measuring beam emitted from a light source on a sample through one side of the pupil of an objective lens, causes light reflected by the sample to pass through the pupil of the objective lens again, focuses the light passing through the pupil of the objective lens on a light-receiving unit, and detects the spot position of the focused light. Especially, this automatic focusing apparatus has a first light-shielding member for shielding light reflected by the lower surface of a transparent thin plate in the vicinity of the focal point of the light reflected by the lower surface of the transparent thin plate, or a second light-shielding member for transmitting therethrough only light reflected by the upper surface of the transparent thin plate in the vicinity of the focal point of the light reflected by the upper surface of the transparent thin plate.