Cadmium is a key and irreplaceable ingredient in infrared detection technology. It is combined with mercury and tellurium to produce the MCT (Mercury-Cadmium-Tellurium) infrared detection material.
When layered on a sensor, an ultra-thin coating of MCT of only a few microns enables high-quality infrared detection. Each sensor contains approximately 0.5 mg of cadmium. The quantity of cadmium present in all infrared detectors produced every year in the world is less than 10 grams.
Infrared detection is a crucial technology in a variety of applications. Historically it was first used in military and space-based deployment. Over the decades it transitioned to industrial and commercial applications, for the preservation of resources and the protection of lives and properties. Examples include the surveillance of industrial sites, gas leak detection, medical imaging, meteorological observations, environmental and agricultural monitoring and surveillance, pharmaceutical formulation development, and plastics recycling. Art restoration experts are now using infrared cameras to examine paintings for artifacts under the pigment, such as original line drawings made with charcoal pencil or chalk.
In a nutshell, the current application sectors for MCT-based infrared cameras are: