Patent · US Expired

Photographic lens system having a large aperture ratio

US4106854A · kind A · utility

10Cited by
2References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 5, 1977
Grant dateAug 15, 1978
Priority date
Expiry dateApr 5, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B9/60
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A gauss type photographic lens system having a large aperture ratio which comprises five components of six lens elements and wherein symmetry of coma is improved and curvature of field, spherical aberration, etc., are favorably corrected by enlarging the airspace comprising a stop and increasing refractive indices of the lens elements arranged on both the sides of said stop.

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