Patent · US Expired

Biocular eyepiece optical system employing refractive and diffractive optical elements

US5151823A · kind A · utility

32Cited by
7References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 23, 1991
Grant dateSep 29, 1992
Priority date
Expiry dateSep 23, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J2229/893
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

In one embodiment, a three-element biocular eyepiece system 40 having a first optical element 42 with at least one diffractive surface 44, a second optical element 48 having a refracting convex surface 50 and a refracting concave surface b 52 is provided. A third optical element 54 having a refracting convex surface 56 and a refracting convex surface 58 is also employed. In another embodiment, a four-element biocular system 60 is disclosed as having an optical element 62 having a refracting concave surface 64 and a refracting convex surface 66, a refractive-diffractive hybrid optical element 68 having a diffractive surface 70 and a refracting convex surface 72, an optical element 74 having a refracting convex surface 76 and a refracting concave surface 78, and an optical element 80 having a refracting concave surface 82 and a refracting convex surface 84. The diffractive surfaces 44 and 70 have a kinoform profile 102 a-d or approximated kinoform profiles 112a-d and 122a-d. Both versions of the biocular eyepiece 40 and 60 provide a biocular eyepiece which has fewer lens elements and a shorter overall length than conventional designs. Both versions of the biocular eyepiece 40 and 60 …

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