Abstract Luminescent polymer optical fibers provide a flexible platform for sensor applications. Photoluminescent liquid-core polymer optical fibers (LiCo-POFs), produced by a co-extrusion of a low refractive index semi-crystalline fluoropolymer sheath with a glycerol core, are presented. Substituting a POF's solid polymer core with a transparent liquid yields luminescent waveguides with extra mechanical flexibility, enabling unique applications like strain sensing. Light conversion and guidance in LiCo-POFs were both achieved simultaneously by doping of the glycerol core with a fluorescent dye. X-ray analysis showed a strong impact of drawing on fiber sheath morphology, and in consequence on both mechanical and optical properties: as the molecular orientation of the sheath increases, tensile strength improves and light attenuation decreases. Excessive drawing leads to micro-voids in the sheath material, causing light scattering, which negatively affects both attenuation and light-conversion. It has been found that both the sheath structure and the sheath and core cross-sectional areas are important design parameters regarding the mechanical and optical performance of LiCo-POFs. A novel principle of an optical strain sensor based on self-absorption peak-shifts is demonstrated; it allows detection of sub-millimeter displacements, both in a reversible elastic as well as in an irreversible inelastic sensor range.

中文翻译：

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用于发光波导应用的液芯聚合物光纤

摘要 发光聚合物光纤为传感器应用提供了一个灵活的平台。光致发光液芯聚合物光纤 (LiCo-POFs) 由低折射率半结晶含氟聚合物鞘与甘油芯共挤出而成。用透明液体代替 POF 的固体聚合物核可产生具有额外机械灵活性的发光波导，从而实现应变传感等独特的应用。LiCo-POFs 中的光转换和引导都是通过用荧光染料掺杂甘油核同时实现的。X 射线分析表明，拉伸对纤维护套形态有很大影响，从而对机械和光学性能产生影响：随着护套分子取向的增加，拉伸强度提高，光衰减降低。过度拉伸会导致护套材料中出现微空隙，从而导致光散射，从而对衰减和光转换产生负面影响。已经发现，鞘结构以及鞘和芯横截面面积都是关于 LiCo-POF 的机械和光学性能的重要设计参数。展示了一种基于自吸收峰位移的光学应变传感器的新原理；它允许在可逆弹性和不可逆非弹性传感器范围内检测亚毫米位移。已经发现，鞘结构以及鞘和芯横截面面积都是关于 LiCo-POF 的机械和光学性能的重要设计参数。展示了一种基于自吸收峰位移的光学应变传感器的新原理；它允许在可逆弹性和不可逆非弹性传感器范围内检测亚毫米位移。已经发现，鞘结构以及鞘和芯横截面面积都是关于 LiCo-POF 的机械和光学性能的重要设计参数。展示了一种基于自吸收峰位移的光学应变传感器的新原理；它允许在可逆弹性和不可逆非弹性传感器范围内检测亚毫米位移。