Patent · US Expired

Zoom lens assembly

US5396367A · kind A · utility

24Cited by
5References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 16, 1993
Grant dateMar 7, 1995
Priority date
Expiry dateApr 16, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B15/144113
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A zoom lens assembly includes, in succession order from the object side, a first fixed lens group of a positive refractive power including a negative lens, a positive lens and a positive meniscus lens; a second movable lens group of a negative refractive power including a negative meniscus lens, a positive lens and a positive lens for effecting a variation of image magnification by moving along an optical axis of the zoom lens assembly; a third fixed lens group of a positive refractive power having at least one aspherical face and including a positive lens and a negative lens; and a fourth movable lens group of a positive refractive power including having at least one aspherical surface and also including negative and positive lenses cemented together.

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