Heart-Rate Monitoring With an Ethyl Alpha-Cyanoacrylate Based Fiber Fabry-Perot Sensor

Abstract

Heart-rate monitoring with an ethyl alpha-cyanoacrylate (EtCNA) based fiber Fabry-Perot (F-P) sensor is presented. The fiber F-P sensor is fixed in a capillary tube by using the EtCNA binder. Due to the lower Young's modulus of the EtCNA, the sensor can detect low frequency vibration with a high sensitivity. The fiber sensor is attached in a specially designed bracket to obtain the stable data. When the sensor with bracket is put on the human body, the heart-rate can be monitored accurately by monitoring the laser intensity variation induced by the heartbeat. Experimental results show that the sensor has the strain sensitivity of 2.57 pm/μN with good responses to low frequency vibrations of 1 Hz, 2 Hz and 3 Hz. The maximum and the minimum mean square deviations of the volunteers' data are 4.434210 and 0.667499, respectively. Moreover, it has good adaptability to measure the heart-rate on different positions of human body, such as wrist, chest and neck. Due to the advantages of small size, low cost, good adaptability, pollution-free and no harm to body. Our proposed sensor is expected to be widely used in heart disease monitoring.