Research On Flexible Mid-infrared Optical Fiber For Biological Tissue CO₂ Laser Ablation

CO₂laser which covers the absorption peaks of soft and hard tissues becomes the first choice for laser ablation of minimally invasive hard biological tissue.Nevertheless,the lack of flexible transmission methods has limited the widespread application of CO₂laser in the ablation of biological hard tissue.Mid-infrared(MIR)fibers become the choice of flexible CO₂ laser transmission due to their high flexibility and miniaturization.Chalcogenide glasses(Ch Gs)are chosen to be ideal materials for flexible MIR fiber due to their stability and wide transmission range from 1.5 to 20?m.Fabrication strategy of multi-material fiber,which is based on the double-crucible method,thin-film rolling and fiber thermal drawing,is expect to provide multi-material fibers which have excellent optical and mechanical properties.This paper aims to choose and prepare different Ch Gs by different thermal matching experiments.Then,the structure of silica crucible was determined by the simulation of the fibers'structure.Finally,ultra-flexible multi-material fibers with controllable diameter and structure,which were applied in the CO₂laser ablation of biological hard tissue,were fabricated via fabrication strategy of multi-material fiber.The main research contents are in the following.High-purity MIR glasses of different components were prepared by melt-quenching method.Thermal matching characteristics of MIR glasses were determined by DSC test and the viscosity tset of different glasses under simulated drawing environment,resulting in co-drawing of As₂Se₃and As₃₇S₆₃.The structure of multi-material fibers was determined by COMSOL.In addition,based on the structure of multi-material fibers,the silica crucible was designed and prepared.The MIR all-glass core-preforms with different diameters and structures were prepared by the double-crucible method.The preforms of MIR step-index optical fibers were prepared by thin-film rolling method.Finally,multi-material fibers were thermal drawing from the preforms.The optical properties of multi-material fibers in this paper are dictated by the Ch G while the mechanical robustness of the fibers stems from a built-in thick polymer jacket,resulting in excellent optical performance and ultra-flexibility.And the flexible transmission of CO₂laser by these multi-material fibers plays and important role in the minimally invasive ablation of hard biological tissue.