Patent · US Expired

Optical device enabling the introduction of a collimated image in an observer's field of vision

US5076664A · kind A · utility

291Cited by
3References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 15, 1990
Grant dateDec 31, 1991
Priority date
Expiry dateMay 15, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B2027/0194
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

Disclosed is an optical device designed to enable an observer to look simultaneously at what is normally in his field of vision and at a colllimated image introduced so as to be superimposed on his field of vision, by total reflections in a strip with parallel faces forming an optical guide. This introduction of a superimposed image is done by means of successive, parallel semi-reflecting panels positioned in the strip and treated so as to be reflective at angles of incidence that get ever smaller with distance from the generator that gives the image. The outside scene is seen, by transparency, through the panels. This device especially concerns helmets for pilots in the field of aeronautics.

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