Patent · US Expired

Viewfinder optics with zero power doublet

US4086000A · kind A · utility

21Cited by
1References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 23, 1976
Grant dateApr 25, 1978
Priority date
Expiry dateAug 23, 1996

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B23/14
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A chromatically neutral viewfinder optical system of positive forward and rearward elements and including therebetween a substantially zero power doublet which neutralizes chromatic errors generated by the positive elements.

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