Cold shield

A cold shield is a device to protect an object from unwanted heating by thermal radiation or light. Usually it is a cooled object with low absorption and high reflectivity.

It can be found in molecular beam epitaxy chambers to protect the growth areas from thermal radiation from hot sources. In cryostats, a radiation shield protects a sample from infrared radiation. An infrared detector is protected from thermal background radiation outside its optical field of view. These devices are usually cooled to the same temperature as the detector.