Most gases can absorb infrared (IR) light. These are gases consisting of two different kinds of atoms, such as CO2, and also CO, NOx and all carbon hydrogens (CH) such as methane, propane or other natural gases employed for heating. IR light is capable of exciting higher energy levels of the molecules by coupling to the dipole moment of the heteroatomic assembly. Heat energy from the IR light is therefore transferred into the gas. Thus, for example, measure and monitor the concentration of important gases in the atmosphere, such as CO2, CO or NOx, by the intensity loss of IR light beam of initially known intensity in a specific spectral region, is a direct measure of the concentration of the matching gas.