Patent · US Expired

Wide-angle attachment for varifocal objective

US4110005A · kind A · utility

29Cited by

3References

8Claims

0Family size

Assignee

Bolex International SA · CH

Inventors

Kurt Bohm · Köngen, DE
Leopold Rollenitz · Neulengbach, AT
Francois Laurent · Yverdon-les-Bains, CH

Key dates

Filing date	Aug 5, 1976
Grant date	Aug 29, 1978
Priority date	—
Expiry date	Aug 5, 1996

Classification

Technology area (CPC G)Physics
CPC primaryG02B15/1465
WIPO fieldOptics
WIPO sectorInstruments

Abstract

A varifocal object selectively focusable upon a normal range of object distances and a substantially shorter macro range can be supplemented by a negative component of one or more lenses whose focal length is less than the depth of the macro range and which forms a virtual image of a nearby object on the object plane of the objective when the latter is adjusted to a predetermined closeup position. A correlating linkage between a seat for the supplemental component and a control member designed to establish the closeup position serves to index the control member in that position or to prevent the emplacement of the supplemental component if the objective is in a different position.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.