Patent · US Expired

Optical instrument with a continuously adjustable zoom

US5499066A · kind A · utility

8Cited by
7References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 21, 1993
Grant dateMar 12, 1996
Priority date
Expiry dateApr 21, 2013

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61B3/1208
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

An optical instrument for indirectly observing an object includes a first lens system for producing a first image of the object, and an adjustable second lens system for producing a second image of the object. The second lens system is continuously adjustable between a first position wherein the second image has maximum magnification and/or a minimum area of view, and a second position wherein the second image is of a minimum magnification and/or a maximum area of view. In one aspect of the invention, the second lens system is a zoom lens system having two substantially fixed conjugate planes. In another aspect of the invention, the instrument defines a folded optical path through the lens systems which includes a generally U-shaped portion so as, in use, to reduce the separation of the observer and the observed object.

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