New glasses, only based on tellurium, have been recently developed, initially in the frame of the Darwin mission led by the European Space Agency (ESA). These glasses transmit light further toward the farinfrared and permit to reach the absorption band of CO2 located at 15 μm as requested by the ESA. Moreover, these telluride glass fiber are also very interesting for FEWS and medical application. Indeed, they give access to the mid-infrared signal of biomolecules beyond 11 μm, where classical selenide glass fibers are blind. Alternatively, in order to fight against global warning, some optical fibers have been developed for the monitoring of the CO2 stored into geological storage area underground. These fibers were doped with Dy3+ which emits a broad fluorescent band embedding the CO2 absorption band at 4.3 μm. thus, these fibers are used both to transmit light and as secondary sources in the mid-infrared.
To conclude, original microstructurated fibers have also been used for mid-infrared sensing. They exhibit a nice sensitivity compared to classical chalcogenide glass fibers.
