Patent · US Expired

Viewfinder optical system

US6052234A · kind A · utility

10Cited by
8References
34Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 16, 1997
Grant dateApr 18, 2000
Priority date
Expiry dateApr 16, 2017

Classification

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

Abstract

A viewfinder optical system has a relay lens system. The relay lens system focuses a primary image to form a secondary image. The relay lens is provided at an optical conjugate point with respect to a pupil. A surface of the relay lens system has an optical power of diffraction. The surface is positioned between the primary image and the optical conjugate point. The surface also has optical power of refraction.

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