Space validation of infrared materials for multi spectral imager onboard a Cubesat mission

Abstract

This master thesis is about the enrichment of the choice of infrared lens materials for both MWIR (mid-wave infrared) and LWIR (long-wave infrared) applications. The work focuses on chalcogenides that offer broad transparency range and excellent thermal properties compared to other IR materials. However, the radiation toler- ance of chalcogenides has not been investigated in the past. The goal is to prove their validation for space missions through the analysis of transmission changes due to radiation encountered in space. First of all, chalcogenides from SCHOTT are compared with common infrared materials according to their optical and thermal characteristics. Then, the space environment and its effect on infrared optical materials is studied. Finally, Proton irradiation and Gamma irradiation tests are carried out on IRG 22 samples in lab- oratory to investigate the radiation tolerance of these materials through possible transmission losses. The transmission of the sample in infrared range is measured before and after irradiation thanks to a Spectrophotometer in order to make some conclusions about the radiation tolerance of chalcogenides. Comparison of transmis- sion spectrum before and after irradiation has shown extremely promising results for the future of these materials.