Patent · US Expired

Direction determining method and apparatus

US4023908A · kind A · utility

17Cited by
2References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 12, 1976
Grant dateMay 17, 1977
Priority date
Expiry dateJan 12, 1996

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01C15/004
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A direction finding system is disclosed in which a predetermined horizontal plane is established by the projection from one location of an image having illuminated and unilluminated portions corresponding to the predetermined horizontal plane. A receiver at a remote location detects the image at two spaced points and produces an indication of the center of the transition zone between the illuminated and unilluminated portions of the projected image.

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