Detection of ultrasound up to 10 MHz frequency using an FBG sensor

In this paper, we present the characterization of an FBG sensor to detect ultrasound in the MHz frequency range which is used in biomedical ultrasound. The linearity, sensitivity, and repeatability of the sensor were tested at 1 MHz, 5 MHz, and 10 MHz in the peak acoustic rarefactional pressure range of 0-1.2 MPa. The FBG showed good linearity (R-Squared=0.98), high sensitivity (0.82 V/MPa at 10 MHz), and high repeatability (coefficient of variation = 5.5%). Our results show the potential of FBG sensors to detect ultrasound for biomedical applications.