| 摘要 |
<p>PURPOSE:To make it possible to measured the amount of carbon dioxide gas stably, by operating a sample signal which is obtained by photoelectric conversion of the intensity of resonance infrared radiation and a reference signal and outputting their ratio as a signal. CONSTITUTION:A gas to be measured is introduced into a furnace core part 102 in a light emitting source 1 through an introducing port 101. The gas is heated to about 200 deg.C with a built-in heater 103. Resonance radiation occurs in carbon dioxide gas, which is included in the gas to be measured. Infrared rays having a specific wavelength and infrared-rays, which have the wavelength different from that of said infrared rays and have the peak wavelength in the vicinity of said wavelength, are inputted into a sensor part 3 through an optical filter part 2. The infrared rays, which are inputted into the sensor part 3 and have the wavelengths with two kinds of frequency band widths, are inputted into an operating part 4 as a sample signal 4S and a reference signal 4R. The signals 4S and 4R are amplified with amplifiers 41 and 42. Thereafter the ratio between the signals is obtained through a logarithm converter circuit 43. Thus the amount of the carbon dioxide can be stably measured for the change in amount of light of a light emitting source and the changes such as contamination of an optical system.</p> |
