| 摘要 |
PROBLEM TO BE SOLVED: To provide a laser type gas analyzer capable of stably and accurately measuring the concentration of gas even in an environment in which the ambient temperature greatly changes. SOLUTION: In the laser type gas analyzer of a frequency modulation type, a signal processing circuit includes both a synchronous detection circuit for detecting the amplitude of double wave signals from output signals of a light-receiving part and an operation part for detecting the concentration of gas to be measured on the basis of a gas absorption waveform present in the output signals. The operation part 208e has the function of detecting the concentration of the gas to be measured on the basis of the difference between a maximum value and a minimum value of the gas absorption waveform, can previously detect and store the timings of occurrence of the maximum value and the minimum value of the gas absorption waveform with trigger signals outputted from a laser-driving signal generation part 204s as a temporal reference, and detects the maximum value and the minimum value of the gas absorption waveform on the basis of these timings. These timings can be corrected on the basis of the ambient temperature. COPYRIGHT: (C)2010,JPO&INPIT |
