Side-Polished Fiber-Optic Line Sensor for High-Frequency Broadband Ultrasound Detection

Sensors

HyoungWon Baac¹  RyunKyung Kim¹  Jeongmin Heo¹  Kyu-Tae Lee² 

[1] Department of Electrical and Computer Engineering, Sungkyunkwan University, Suwon 16419, Korea;Department of Physics, Inha University, Incheon 22212, Korea;

关键词: ultrasound sensor;    fiber-optic sensor;    optical ultrasound detector;    side-polished fiber;    high-frequency ultrasound;   

DOI  :  10.3390/s19020398

来源: DOAJ

【 摘 要 】

We demonstrate a side-polished fiber-optic ultrasound sensor (SPFS) with a broad frequency bandwidth (dc–46 MHz at 6-dB reduction) and a wide amplitude detection range from several kPa to 4.8 MPa. It also exhibits a high acoustic sensitivity of 426 mV/MPa with a signal-to-noise ratio of 35 dB and a noise-equivalent pressure of 6.6 kPa (over 1–50 MHz bandwidth) measured at 7-MHz frequency. The SPFS does not require multi-layer-coated structures that are used in other high-sensitivity optical detectors. Without any coating, this uses a microscale-roughened structure for evanescent-field interaction with an external medium acoustically modulated. Such unique structure allows significantly high sensitivity despite having a small detection area of only 0.016 mm2 as a narrow line sensor with a width of 8 μm. The SPFS performance is characterized in terms of acoustic frequency, amplitude responses, and sensitivities that are compared with those of a 1-mm diameter piezoelectric hydrophone used as a reference.

【 授权许可】

Unknown