Infrared gas analysis and non dispersive infrared analysis

Many compounds can form molecular vibrations under the excitation of infrared light. Therefore, this molecular structure absorbs infrared radiation. The absorption spectrum depends on the molecular structure, degrees of freedom of molecular motion, elements, types of compounds, spatial structure, and bonding forces. Therefore, every substance has its own unique absorption spectrum, for example, carbon dioxide molecules can excite bending and stretching vibrations. Additional rotational motion between different molecular axes also occurs, which is superimposed on the spectral vibration, making its spectral structure more detailed.

What are the advantages of Non Spectral Infrared Analysis (NDIR)?

Compared to infrared spectrometers, non dispersive infrared (NDIR) gas analysis has significantly lower costs. However, this method can only be used when the type of gas to be measured is known and the quantity is small.