10 February 1995 Remote passive optically addressed and encoded sensor for gaseous pollutants
Author Affiliations +
Proceedings Volume 2366, Optical Instrumentation for Gas Emissions Monitoring and Atmospheric Measurements; (1995) https://doi.org/10.1117/12.205580
Event: Optical Sensing for Environmental and Process Monitoring, 1994, McLean, VA, United States
Abstract
A passive optical chemical sensor is described that responds to interrogation by a pulsed near- IR optical transceiver over a line-of-sight path. The chemical detection method is based on changes in the near-IR optical transmittance of a dye film on a glass substrate that forms an integral part of the sensor. The response of the sensor to a chemical is encoded onto the signal returned to the transceiver using a re-entrant optical-fiber delay line. For each interrogating optical pulse, this sensor produces a characteristic sequence of return pulses from which the presence of a chemical can be determined. The uniquely identifiable response of the sensor can also be used to identify individual sensors. The sensor is capable of quantitative measurements, it is relatively insensitive to atmospheric conditions over the transmission path, and it has a high signal-to-noise ratio. The operation of the sensor with a semiconductor-based laser transceiver is demonstrated using reagents which exhibit near-IR optical changes in the presence of specific pollutants. This technique is readily adaptable for the sensing of a wide range of hazardous chemicals in both inaccessible and dangerous environments. Modified sensors can also be adopted for use in area protection applications.
© (1995) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Frank Kvasnik, Nicola J. Hortin, Luis E. Norena-Franco, "Remote passive optically addressed and encoded sensor for gaseous pollutants", Proc. SPIE 2366, Optical Instrumentation for Gas Emissions Monitoring and Atmospheric Measurements, (10 February 1995); doi: 10.1117/12.205580; https://doi.org/10.1117/12.205580
PROCEEDINGS
7 PAGES


SHARE
Back to Top