Patent ID: 8155890
Filing Date: 2012-04-10
Classification: G01N

Abstract:
1. An exhaust gas analysis method, comprising: applying a laser beam from a laser beam generator of an exhaust gas analysis apparatus to the exhaust gas discharged from an internal combustion engine; receiving, at a laser beam receiver of the exhaust gas analysis apparatus, the laser beam that has passed through the exhaust gas; and measuring a concentration of any of the components contained in the exhaust gas based on the received laser beam, wherein the measuring comprises: detecting an absorption spectrum of the laser beam absorbed in the exhaust gas by using the received laser beam, calculating the concentration of the component contained in the exhaust gas, the temperature of the exhaust gas, and the pressure of the exhaust gas by using the absorption spectrum without using a pressure sensor, wherein the exhaust gas temperature is calculated from the ratio between the transmitted light intensities at least two wavelengths selected from the absorption spectrum for H correcting the calculated concentration of the component contained in the exhaust gas by using the calculated exhaust gas temperature and the calculated exhaust gas pressure, wherein the measuring is performed by the exhaust gas analysis apparatus.