Patent · US Expired

System and method for measuring distance

US3937574A · kind A · utility

12Cited by
7References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 29, 1973
Grant dateFeb 10, 1976
Priority date
Expiry dateOct 29, 1993

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01S17/08
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A pair of light intensity detectors are spaced apart in range and an arrangement is included for reflecting light from a target to the detectors. The system measures target range by dividing the output signal of one of the detectors by a signal which is a function of the difference between the output signals of the two detectors to produce a quotient signal. To avoid low signal instability problems, the difference signal is generated in one embodiment of the system by subtracting only a selected fraction of the output signal of the far detector from that of the near detector. A substantially linearized output signal representing target range is produced in this system embodiment by raising the quotient signal to a selected power. The light detectors are preferably incorporated in input circuits which are temperature compensated.

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