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:
Dec. 18, 1979
Filed:
Nov. 14, 1977
Other;
Abstract
In order to establish a predetermined position of focusing or focal-length adjustment for an optical objective, a mechanism for the axial shifting of one or more lens members has a lost-motion zone in its operating range in which a continuing displacement of a control element does not change the focal length and/or distance of the objective. The halting of the lens shift (or, possibly, a compensatory displacement of an otherwise stationary lens member) can be brought about mechanically, with the aid of suitably shaped cam tracks, or electromechanically, via analog or binary position sensors. Arrival of the adjusting mechanism in the lost-motion zone may be signaled to the user by a detent, by a change in frictional resistance, or by a visual or acoustical indicator.