摘要 |
PROBLEM TO BE SOLVED: To provide a laser gas analysis device capable of reducing a processing time for fitting.SOLUTION: The laser gas analysis device comprises: a laser drive unit 2 that generates a driving signal for driving a wavelength variable semiconductor laser 1; a waveform processing unit 6 that, by using a modulation signal, synchronously detects output of light detection units 4 and 5 receiving the output light of the wavelength variable semiconductor laser through a gas cell 3, thereby extracting harmonic components of the output signal of the light detection units and performing waveform processing; and a concentration calculation unit 7 that calculates gas concentration on the basis of the waveform thus obtained. The laser drive unit generates as a driving signal a signal obtained by superposing the modulation signal on a sweep signal and synchronizing with the cycle of the sweep signal to switch a wavelength amplitude of the modulation signal to two levels of large and small. The waveform processing unit comprises: a gas identifying unit for identifying a gas component existing in the gas cell on the basis of the harmonic component of the output signal; and a waveform separation unit for separating the waveform of harmonic components of the output signal by each gas component by using identified gas component information. |