Emerging Technologies for Fiber-Optic-Based Sensors in Biomedical Domain: A Review and Recent Developments

Fiber-optic sensor (FOS) technology, a proximate of optoelectronics and fiber-optic communications, has profound ability to replace the existent biomedical sensors. Subsequent mass production of these sensors, driven by advantages such as compact size, immunity to electromagnetic interference (EMI), lower power consumption, ease of fabrication, durability, robustness, distributive, and remote sensing capabilities, calls for their usage in various medical and healthcare applications. Multiple fiber-optic-based sensing technologies were being used inherently in the clinical diagnosis of different abnormalities. Consenting to this, an extensive review on recent developments in seven fiber-optic-based sensing methodologies, namely, grating-based sensors, fiber-optic plasmonic sensors (FOPSs), photonic crystal fibers (PCFs), interferometric sensors (ISs), distributed sensors, fiber-optic endoscopes (FOEs), and fiber-optic evanescent wave-based sensors (FO-EWSs) for the past five years, is provided in this article chronologically. Their distinctiveness was formulated on the rationale of principle of operation, interrogation techniques, performance metrics, merits, demerits, and clinical applicability. This study reports their existing trends, along with the confinements that require profound attention to further the position of these sensors commercially. Finally, a constructive elucidation on the assessment was made, which assists in the betterment of already available biomedical sensors in the definitive identification of multifarious medical conditions.