Elaboration by additive manufacturing of microstructured optical fiber for infrared sensing application

Additive manufacturing offers new opportunities for designing complex glass preforms that cannot be achieved by conventional methods. In this work, we demonstrate the fabrication of microstructured chalcogenide-glass fibers for mid-infrared sensing using a filamentation 3D-printing process. Two fiber architectures were produced: a conventional exposed-core fiber (ECF) and a novel Y-shaped exposed-core fiber (Y-ECF), made possible only through additive manufacturing of the preforms. Both fibers exhibit attenuation below 4 dB/m in the 3–10 μm wavelength range with a minimum attenuation of 0.5 dB/m at 5.5 μm. Fiber evanescent wave spectroscopy (FEWS) measurements performed on ethanol reveal that the printed fibers outperform a standard single-index TAS fiber. The Y-ECF shows the highest sensitivity due to its fully open geometry and thin Y-core arms, which enhance the evanescent field and interaction with the surrounding medium. These results highlight the potential of 3D printing for rapid prototyping of advanced microstructured infrared fibers and open new perspectives for chemical and biological sensing in the mid-infrared. • 3D printing enables complex chalcogenide preforms for mid-IR fiber sensing • A fiber drawn from a printed chalcogenide preform can exhibit optical losses below 1 dB/m. • Novel Y-shaped fiber exhibits highest FEWS sensitivity vs. conventional fibers