Patent ID: 9377397
Filing Date: 2016-06-28
CPC Classification: G01N

Claim Text:
1. A method of calibrating a system that detects a presence of a pollution component within an exhaust gas within an exhaust passageway, the method including: providing a probe with a measurement cell for in-situ measurement of the exhaust gas wherein the probe operates to detect the pollution component from the exhaust gas, the probe including a guide path portion that travels through a fixed shield, a laser that emits a beam in the mid-infrared range and is located on one end of the guide path portion, said measurement cell on an opposite end of the guide path portion, and a seal at an end of the measurement cell, the fixed shield being located within the exhaust passageway, and the measurement cell being able to be exposed to the exhaust gas within the exhaust passageway; moving the measurement cell out of the exhaust passageway and within the fixed shield to isolate the measurement cell from the exhaust gas, wherein the seal and the fixed shield are configured to prevent the exhaust gas from entering the measurement cell during the calibration of the system; providing a source of a reference gas that is transported to the measurement cell; operating the laser of the probe with the beam directed to the measurement cell that includes the reference gas, such that the beam interacts with the reference gas; receiving at a detector the laser beam subsequent to the interaction of the beam with the reference gas; and determining an accuracy and a calibration of the system from the at least one or more constituents of the reference gas.