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:
Nov. 11, 1986
Filed:
Mar. 27, 1985
Olympus Optical, Tokyo, JP;
Abstract
A zoom lens assembly with an auto-focus function includes first and second lens groups, and a control device for causing a drive mechanism to rotate a distance-presetting ring which moves one of the lens groups, to adjust a focus in accordance with a signal sent from a light-receiving element for indicating the focused state of a foreground object. A line pattern substrate is arranged to move with the distance-presetting ring. A change in the focal length caused by the rotation of a zoom ring is sensed by a substrate detecting element which informs the control device of that extent to which the distance-presetting ring is to be rotated in order to assure a proper focus notwithstanding the changed focal length. The corrective rotation of the distance-presetting ring is detected by movement of the line pattern substrate relative to the detecting element. The light-receiving element is supplied with a beam of light reflected from the foreground object through the first and second groups of lenses.