Patent · US Expired

Optically-based chemical detection system

US5545897A · kind A · utility

52Cited by
10References
46Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 4, 1994
Grant dateAug 13, 1996
Priority date
Expiry dateOct 4, 2014

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02A50/20
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An in-situe chemical gas or fluid analyzer for vehicles, industrial, environmental and process control applications. As applied to a vehicle (1) having an internal combustion engine, the analyzer includes: (i) a source of electromagnetic radiation (14, 16); and (ii) a sampling cell (12) which collects emission gases of interest and which is capable of withstanding hostile environments while preserving a "clear" optical path between the sensor sampling cell and the source of radiation. The analyzer further includes: (iii) a solid state sensor (24, 26, 28, 30, 32 ) of monolithic construction which selectively detects electromagnetic radiation that is absorbed or emitted by one or more chemical species of interest, that compensates for temporal and spatial variations in illumination level provided by the source, and that provides an electrical signal output, in either analog or digital format, that is related to the measured concentrations. The sensor includes, in combination, a plurality of highly sensitive electromagnetic radiation detectors (26), spectral filters (24) which may utilize multiple layers of deposited dielectric thin films and/or selectively absorbing layers, and low n…

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