| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a highly accurate apparatus for measuring isotope gases which utilizes a non-dispersive type infrared analyzer and is not affected due to the quantity change of light of a light source. SOLUTION: An infrared light source 18 is arranged inside a measurement cell 15, in which a sample gas is circulated. Band-pass filters 19, 21 and detectors 20, 22 for measuring absorption of 12CO2 and 13CO2 are set to both end faces of the cell 15. Lights, generated in both directions from the infrared light source 18 which drives to flicker by a predetermined cycle, are detected by the detectors 20 and 22. Since the same light source is utilized, effects due to the quantity change of light for a short time, even if present, can be offset. Moreover, since no mechanical chopper is used, variations in the quantity of light by a velocity change of the chopper can be avoided.</p> |
