Fiber Optic Sensor Applications for Vital Signs Monitoring: A Review

In this work, the research articles in fiber optic sensors (FOS) for vital signs monitoring have been reviewed. Particularly, the FOS concepts of the body temperature (BT), respiratory rate (RR), and also heart rate (HR) detections have, preliminarily, been described for emphasizing the fundamental principles. Furthermore, the reviewed sensing systems have been categorized according to the prioritized vital signs, target area, patient positioning, and also implemented the FOS type. It was, consequently, seen that the HR and RR monitoring system were frequently presented, while the BT detection was rarely reported. Moreover, most FOS could be optimized to detect multiple vital signs with a single setup. Meanwhile, the target area was selected based on the patient position, for examples chest area for either standing / sitting subject, and also back area for supine position. Additionally, the fiber bending and fiber Bragg grating (FBG) sensors have been widely utilized. Specifically, the distinctive points of the fiber bending sensors were the cost-effectiveness, small sizing, and also less computational intensive, whereas the FBG sensors were more appropriate for the multiple target monitoring. Surprisingly, the fiber optic Mach-Zehnder and also Fabry-Perot interferometers have been proposed as well. In this perspective, it could be implied that the FOS based vital signs monitors would be developed to be more available and reliable for medical applications in the future.