| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an infrared gas sensor capable of improving the long-term stability of measuring accuracy.SOLUTION: An optical system 3 is arranged between an infrared radiation element 10 and an infrared detection element 20a. The optical system 3 sets transmission factors of infrared rays to a first transmission wavelength region including an infrared absorption wavelength by detection target gas and a second transmission wavelength region set on a longer wavelength side than the first transmission wavelength region, respectively, and an average transmission factor of the second transmission wavelength region is lower than that of the first transmission wavelength region. A control unit 51 controls a drive circuit 5 in time series so that the drive circuit 5 drives the infrared radiation element 10 by pulses under a first drive condition and a second drive condition different in the peak wavelength in a radiant energy distribution of the infrared radiation element 10, respectively. A signal processing unit 4 estimates the concentration of the detection target gas using the comparison of a first output signal from the infrared detection element 20a under the first drive condition with a second output signal from the infrared detection element 20a under the second drive condition.</p> |
