| 摘要 |
A spectrophotometer is provided, including a light source for irradiating light into a sample gas, a photodetector for detecting light transmitted through the sample gas, an optical filter, and an operation device for calculating a concentration of an actual gas to be measured, contained in the sample gas based on a detection signal value obtained from the photodetector. The operation device calculates the concentration of the actual gas based on function alpha for associating a concentration of a substitute gas with the actual gas obtained from a reference instrument, function beta for associating a relation between a light absorption of the actual gas and the substitute gas in the reference instrument, with a relation between a light absorption of the actual gas the substitute gas in a calibration instrument, and a function indicating a relation between the concentration of the substitute gas and the detection signal value. |
