Patent · US Expired

Wide-angel aspheric zoom lens

US5552937A · kind A · utility

16Cited by
6References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 7, 1994
Grant dateSep 3, 1996
Priority date
Expiry dateApr 7, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B13/18
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A first lens group having a negative refracting power and a second lens group having a positive refracting power are arranged in order from the photographing object side. Zooming is performed by changing the aerial interval between the first and second lens groups, and both the first and second lens groups have one or more aspheric surfaces. The first lens group includes two negative lenses and a positive lens which are arranged in order from the object side, and the second lens group includes a positive lens, a cemented lens having a positive lens and a negative lens, and a positive lens which are arranged in order from the object side.

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