CF4 gas concentration measurement method and CF4 gas concentration measurement apparatus

摘要

PROBLEM TO BE SOLVED: To provide a method for measuring a CFgas concentration and a device for measuring a CFgas concentration capable of easily detecting, with high reliability, the CFgas concentration of a gas to be inspected containing the CFgas and a CFgas.SOLUTION: The concentration of a CFgas is measured by correcting gas detection output corresponding to the luminous energy of an infrared ray in a first wavelength region having a center wavelength of 7850±50 nm, the gas detection output being obtained by infrared ray detection means with respect to a gas to be inspected containing the CFgas and a CFgas. The correction is made by correction output obtained by (1) a procedure for acquiring the concentration of the CFgas on the basis of the absorbance of an infrared ray in a second wavelength region having a center wavelength of 9035±50 nm, and (2) a procedure for acquiring, as the correction output, the gas detection output obtained by checking the obtained concentration of the CFgas against a calibration curve previously acquired by measuring the absorbance of the infrared ray in the first wavelength region. The device for measuring the CFgas concentration has signal processing means by which the above method is executed.