Patent · US Expired

Change-over device for zoom lens

US4333712A · kind A · utility

13Cited by
4References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 1, 1980
Grant dateJun 8, 1982
Priority date
Expiry dateApr 1, 2000

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B7/105
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A zoom lens including a change-over device or mechanism for changing between a normal photographing mode and a macro photographing mode and in which zooming and focusing operations for normal photographing are carried out with a single operational barrel while focusing and zooming for the macro photographing mode are carried out with a second or macro photographing operational barrel. A change-over rod is slidably mounted on a support barrel which supports each of four lens groups. The change-over rod is selectively engageable and disengageable from the normal operational barrel and a macro operational barrel. When the change-over rod is engaged with the normal operational barrel for macro photographing, rotation of the normal operational barrel is prevented and each of the lens groups are moved integrally with one another. In the other position of the change-over rod in which the end thereof is disengaged from the normal operational barrel, focusing and zooming are carried out by operating the normal operational barrel.

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