US 11,796,458 B2
Concentration measurement device
Masaaki Nagase, Osaka (JP); Kazuteru Tanaka, Osaka (JP); Masahiko Takimoto, Osaka (JP); Kouji Nishino, Osaka-shi (JP); and Nobukazu Ikeda, Osaka (JP)
Assigned to FUJIKIN INCORPORATED, Osaka (JP)
Appl. No. 17/423,500
Filed by FUJIKIN INCORPORATED, Osaka (JP)
PCT Filed Jan. 21, 2020, PCT No. PCT/JP2020/001917
§ 371(c)(1), (2) Date Jul. 16, 2021,
PCT Pub. No. WO2020/158506, PCT Pub. Date Aug. 6, 2020.
Claims priority of application No. 2019-016404 (JP), filed on Jan. 31, 2019.
Prior Publication US 2022/0074851 A1, Mar. 10, 2022
Int. Cl. G01N 21/3504 (2014.01)
CPC G01N 21/3504 (2013.01) [G01N 2201/062 (2013.01); G01N 2201/1211 (2013.01); G01N 2201/1218 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A concentration measurement device comprising:
a measurement cell having a flow path through which a gas flows;
a light source for generating incident light to the measurement cell;
a photodetector for detecting light emitted from the measurement cell;
a pressure sensor for detecting a gas pressure in the measurement cell;
a temperature sensor for detecting a gas temperature in the measurement cell; and
an arithmetic circuit for calculating a concentration of the gas based on an output of the pressure sensor, an output of the temperature sensor, an output of the photodetector, and a plurality of extinction coefficients stored in advance in a memory,
wherein the arithmetic circuit is configured to calculate the concentration using an extinction coefficient determined from the plurality of extinction coefficients based on the output of the temperature sensor, and configured to calculate the concentration by using a correction factor set for each type of gas to correct the extinction coefficient of a reference gas.