In evacuated process chambers, specific demands are placed on materials. This is because the synthetics from conventional reflectors or film might outgas traces of substances in the vacuum and thereby endanger the highly purified production process.
For this application, IMOS offers vacuum reflectors. These can be conveniently scanned by sensors extrinsic to the vacuumed process chamber. You will find IMOS vacuum reflectors, for instance, successfully deployed in plants where silicon is processed.