GAS ANALYZING METHOD AND GAS ANALYZING DEVICE

摘要

Provided is a gas analyzing method in which: infrared light is made incident on a sample gas, the infrared light having been tuned to a wavelength that corresponds to one absorption line of a target gas included in the sample gas that has been introduced into a gas cell; a sample signal value is measured, such value corresponding to the intensity of transmitted light, out of the infrared light, that has passed through the gas cell; the sample gas inside the gas cell is evacuated and then replaced with a reference gas; a reference signal value is measured, such value corresponding to the intensity of transmitted light, out of the infrared light, that has passed through the reference gas; and a gas density at the one absorption line is calculated from the ratio of the sample signal value to the reference signal value.