CAI 700 NDIRAdopting modular design, it can be integratedNDIRMultiple detection modules such as infrared and electrochemical.

Most gases can absorb infrared light of different wavelengths and have unique infrared spectral absorption characteristics. The light attenuation caused by absorption satisfies Lambert Beer's law,
According to this law, the concentration of a gas is directly proportional to the attenuation of the intensity of infrared light at a specific wavelength.

When the infrared light generated by the instrument's infrared light source passes through the measuring chamber, the measured gas in the chamber will absorb specific wavelengths of infrared light, causing it to attenuate,
By detecting the intensity of infrared light at this frequency through the detector on the other side and comparing it with the intensity of the reference detector, the attenuation coefficient of infrared light at this wavelength can be determined,
According to Lambert Beer's law, gas concentration can be calculated.