Patent · US Expired

Surveying instrument

US4346989A · kind A · utility

33Cited by
2References
1Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 30, 1979
Grant dateAug 31, 1982
Priority date
Expiry dateAug 30, 1999

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01C3/30
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A tacheometer includes a distance measuring module whose output indicates the distance to a target by a phase shift in an output signal relative to a reference signal. An angle measuring module has an output that indicates angular displacement by a phase shift in another output signal relative to a different reference signal. A single phase comparison module alternately measures both phase shifts.

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