LN2 Cold Testing:
Windows or filters used in photovoltaic infrared cameras may have a requirement to operate at the same low temperature as the cooled detector. Reynard has manufactured many variants of these infrared windows and filters. To validate durability at low temperature, one-inch witness samples are placed on a cold shield in a liquid nitrogen (LN2) Dewar, and brought down to the operational temperature of 77°K. The Dewar is used in conjunction with a spectrometer in a customized fixture to perform spectral measurements. Spectral transmission of the witness sample can be measured across any visible or infrared spectral band out to 20µm.