Patent · US Expired

Fluid opacity sensor

US5206711A · kind A · utility

11Cited by
6References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 11, 1990
Grant dateApr 27, 1993
Priority date
Expiry dateJun 11, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N2201/12769
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A fiber optic fluid opacity sensor includes a light source (12) transmitting light to dividing means (14) for providing a sample light signal (18) and a reference light signal (20) to dual photodetectors (26, 28). Sample and reference optical pathways (19, 21) are defined by optical fibers (18, 20) spaced apart from and axially aligned with the photodetectors (26, 28) at a predetermined distance. Signal processing means (30) takes the log ratio output of the signals from the photodetectors (26, 28) for cancelling the effect of light source drift since the same source (12) is common to both for measuring the light transmission and determining opacity therefrom. A sample probe (40) contains the photodetectors (26, 28) and the sample and reference optical pathways (19, 21). The light source (12) and the signal processing means (30) are situated outside of the probe (40) and by virtue thereof outside of the sample process line (48).

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