Abstract
In recent years, concern about an environmental problem is increasing more notably. Then, the gas composition measurement technology is becoming much more important in association with tightening of regulations. However, chemical-analysis methods such as gas chromatography are not sufficient to satisfy these requirements from a viewpoint of sensitivity and response. Because of these factors, development of sensitive and fast response gas composition evaluation/diagnostic technology is eagerly anticipated to meet the environmental needs. This research aims at developing the technology which can measure the various compositions with high sensitivity and response compared to conventional equipment. The tunable diode laser absorption spectroscopy using the hollow fiber has been developed to satisfy above requirements. By using a hollow fiber, misalignment of an optical axis and vulnerability of measurement environment such as vibration can be greatly reduced with sensitive and fast response features. It was also demonstrated that this method can be applicable to measure gas compositions in engine exhaust with a range of millisecond response time.
