To provide a gas composition measuring instrument constituted so as to eliminate the conventional point at issue expensive and difficult to perform real time monitoring, and utilizing the correlation data of preliminarily stored compositional fluctuations with phase difference without measuring acoustic velocity not only to enhance detection sinsitivity but also to enable real time output.
In the gas composition measuring instrument equipped with a transmitter for transmitting an ultrasonic wave and a receiver for receiving the ultrasonic wave transmitted from the transmitter and detecting the concentration or mixing ratio of the gas to be measured present between the transmitter and the receiver, the correlation data of the compositional fluctuations of the concentration or mixing ratio of the gas to be measured with the phase difference from a reference phase generated in the receiver accompanied by the compositional fluctuations of the gas to be measured is preliminarily stored in a memory means and the correlation data is used to output the concentration or mixing ratio of the gas to be measured from the phase difference between the phase detected by the receiver and the reference phase.
ISHIKAWA TOSHIAKI
DEGUCHI MIKIO
TODA TOSHIHIKO
