The aim of this paper is to provide a comprehensive review of mode-division and spatial-division optical fiber sensors, mainly encompassing interferometers and advanced fiber gratings. Compared with their single-mode counterparts, which have a very mature field with many highly successful commercial applications, multimodal configurations have developed more recently with advances in fiber device fabrication and novel mode control devices. Multimodal fiber sensors considerably widen the range of possible sensing modalities and provide opportunities for increased accuracy and performance in conventional fiber sensing applications. Recent progress in these areas is attested by sharp increases in the number of publications and a rise in technology readiness level. In this paper, we first review the fundamental operating principles of such multimodal optical fiber sensors. We then report on the theoretical formalism and simulation procedures that allow for the prediction of the spectral changes and sensing response of these sensors. Finally, we discuss some recent cutting-edge applications, mainly in the physical and (bio)chemical fields. This paper provides both a step-by-step guide relevant for non-specialists entering in the field and a comprehensive review of advanced techniques for more skilled practitioners.

中文翻译：

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模分和空分光纤传感器

本文的目的是对模分和空分光纤传感器进行全面回顾，主要包括干涉仪和先进的光纤光栅。与具有非常成熟的领域和许多非常成功的商业应用的单模对应物相比，多模配置最近随着光纤器件制造和新型模式控制装置的进步而发展。多模态光纤传感器大大拓宽了可能的传感模式的范围，并为提高传统光纤传感应用的准确性和性能提供了机会。出版物数量的急剧增加和技术准备水平的提高证明了这些领域的最新进展。在本文中，我们首先回顾了这种多模态光纤传感器的基本工作原理。然后，我们报告了允许预测这些传感器的光谱变化和传感响应的理论形式和模拟程序。最后，我们讨论了一些最近的前沿应用，主要是在物理和（生物）化学领域。本文既提供了与进入该领域的非专业人士相关的分步指南，也为更熟练的从业者提供了先进技术的全面回顾。