Two-Photon 3D-Printed Fabry–Pérot Interferometric Sensor for Ultrasensitive High-Frequency Ultrasonic Detection
Jialin Wen, Tianyu Yang, Zeyu Zheng, Tingwei Xi, Zihan Liu, Heming Wei, Linfeng Lan, Weifeng Deng, Huanhuan Liu, Chunlei Yang, Yuming Dong
Abstract
A novel fiber extrinsic Fabry-Pérot interferometric ultrasonic sensor for detecting high-frequency ultrasonic signals is proposed and fabricated. The diaphragm structure features an anti-outer-ring clover design. Finite element simulation is employed to determine optimal parameters before directly printing the sensor onto the fiber tip using two-photon 3D printing technique. Experimental results indicate that the sensor achieves a signal-to-noise ratio of 67 dB@300 kHz, a mechanical sensitivity of 1362 nm/kPa, and a noise equivalent acoustic signal level of 3.98 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mu$</tex-math></inline-formula>Pa/Hz<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^{1/2}$</tex-math></inline-formula> @300 kHz. The proposed fiber sensor offers a new approach for sensing weak ultrasonic signals and is expected to be applied in various ultrasonic detection fields.