Patent · US Expired

NDIR gas sensor

US5747808A · kind A · utility

25Cited by
7References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 13, 1996
Grant dateMay 5, 1998
Priority date
Expiry dateJun 13, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N21/61
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A miniaturized NDIR gas sensor is manufactured using semiconductor micromachining techniques from a semiconductor material such as Si or GaAs. The NDIR gas sensor comprises an optical waveguide, a light source at one end of the waveguide, at least one light detector at the end of the waveguide opposite the light source, a diffusion type gas sample chamber formed within the waveguide and interposed in the optical path between the light source and light detector so that the light source and light detector are thermally isolated from the gas sample, and a separate bandpass filter interposed between the light source and each light detector. A miniaturized NDIR gas sensor is also provided in which the light source and light detector are located on the same end of the optical waveguide is also provided. Because the NDIR sensor is fabricated out of a semiconductor material, the source driver and signal processing electronics may be added directly to the sensor using integrated circuit fabrication techniques. Particles and smoke and dust may be kept out of the sample chamber by application of a gas permeable membrane over apertures in the sample chamber walls.

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