Patent · US Expired

Camera zoom lens

US5541772A · kind A · utility

9Cited by
9References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 7, 1993
Grant dateJul 30, 1996
Priority date
Expiry dateDec 7, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B15/142
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A camera zoom lens consists of five lens elements arranged in two groups, in which the first three elements form a front lens group with a positive refractive power and the last two elements form a rear lens group with a negative refracting power. In the lens system, the front lens group is composed of a negative first lens element having its concave surface directed toward the object side of the lens system, a negative second lens element, and a positive third lens element; the rear lens group consists of a positive fourth lens element having its concave surface directed toward the object side of the lens system and a negative fifth lens element having its concave surface directed toward the object side of the lens system. The zoom lens system is suitable for use in a 35 mm lens shutter camera.

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