Dynamic Characterisation of Fibre-Optic Temperature Sensors for Physiological Monitoring

Abstract

Fast, miniature temperature sensors are required for various biomedical applications. Fibre-optics are particularly suited to minimally invasive procedures, and many types of fibre-optic temperature sensors have been demonstrated. In applications where rapidly varying temperatures are present, a fast and well-known response time is important; however, in many cases, the dynamic behaviour of the sensor is not well-known. In this article, we investigate the dynamic response of a polymer-based interferometric temperature sensor, using both an experimental technique employing optical heating with a pulsed laser, and a computational heat transfer model based on the finite element method. Our results show that the sensor has a time constant on the order of milliseconds and a −6 dB bandwidth of up to 178 Hz, indicating its suitability for applications such as flow measurement by thermal techniques, photothermal spectroscopy, and monitoring of thermal treatments.

Recent Advances in Biomedical Photonic Sensors: A Focus on Optical-Fibre-Based Sensing

“…Most of these works are linked to tissue laser ablation. However, temperature profiling and mapping also have applications in other medical procedures such as intravascular flow measurement, hot-wire anemometry, radiofrequency, or photothermal spectroscopy, among others [ 38 ].…”

“…Finally, often, the dynamic response of sensors due to rapid temperature changes is not available. In 2020, Coote et al implemented a Fabry–Perot (FP) cavity in a polymer-based optical fibre for the dynamic response of the temperature sensor [ 38 ]. They combined optical heating with pulsed laser and heat transfer models, suggesting the sensor’s suitability for monitoring temperature in thermal treatments.…”

Pengaruh Sensitivitas Suhu Dengan Metode Couple-Mode Terhadap Fiber Bragg Grating Fiber Optik

“…Perubahan panjang kisi yang disebabkan oleh ragangan pada serat juga akan mempengaruhi periode kisi dan indeks bias yang diinduksi regangan-optik. Regangan ini dipengaruhi juga oleh perubahan temperatur yang berpengaruh terhadap material serat optik jika temperatur berubah dari suhu awalnya [14]. Biasanya, kenaikan suhu membuat ion-ion material bergerak lebih cepat daripada penurunan suhu.…”

Research on the Frequency Response and Dynamic Range of the Quadrature Fiber Optic Fabry–Perot Cavity Microphone Based on the Differential Cross Multiplication Demodulation Algorithm

“…In recent years, interference-type FOMs have become a research hotspot, especially FOMs based on Fabry-Perot (F-P) interferometers [9][10][11], which are of great interest due to their high sensitivity, simple structure, and easy fabrication. However, the dynamic range of the fiber optic F-P cavity microphone is largely limited by the intensity demodulation method based on a linear region of the interference spectrum [12][13][14]. To extend the dynamic range of the fiber optic F-P cavity microphone, a quadrature signal demodulation technique has been proposed, which consists of the following two main aspects [15][16][17][18]:…”