Patent · US Expired

Downward viewing optical device

US5422759A · kind A · utility

6Cited by
2References
15Claims
0Family size

Inventor

Key dates

Filing dateDec 21, 1992
Grant dateJun 6, 1995
Priority date
Expiry dateDec 21, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B27/021
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An optical viewing apparatus adapted to be worn on the face which enables the wearer to view directly downward while maintaining an erect head and a horizontal line of sight.

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