How does a mid-IR sensor work?

Schematic of mid-infrared trace gas sensor. Light from a Mid-IR laser source is directed into a small cavity filled with air, exhaled breath or other gas sample. A detector records how much light is absorbed by trace gases in the sample, making it possible for scientists to identify the chemical composition of the gas.

This thin strip is the actual QC laser, also visible are the fine gold wires used to make electrical contact with the device. The copper block serves as a mount and heat sink.

Quantum Cascade (QC) lasers are among the many technological improvements that make mid-IR sensing a possibility. QC lasers cover the entire mid-IR wavelength range (3 – 17 mm) by tailoring thicknesses of the same material.

Check out the list of MIRTHE members supplying QCLs