Diode Laser Based Sensors for Environmental Monitoring

Environmental monitoring of trace gas species is becoming an increasingly important area of concern for both private and government sectors. Desirable characteristics for such sensors include portability, low power requirements, high sensitivity, rapid response and low maintenance. A semiconductor laser based sensor can meet all of these requirements. Recent advances in semiconductor laser technology have produced lasers which have better mode quality, improved tunability, increased output powers and a wider range of wavelengths (particularly in the near-IR and visible regions). We are proposing to build a laser diode based system for continuous emissions monitoring of NO2[sub] and Oxygen which shall take advantage of these recent technological advances. Phase I research will concentrate on optimizing the technique for measurement of NO2[sub]. A diode laser-based sensor for simultaneous measurement of multiple gases will be designed for subsequent development and field testing in Phase II.