A wideband sensitive needle ultrasound sensor based on a polarized PVDF-TrFE copolymer piezoelectric film has been developed, which is capable of providing a noise equivalent pressure of 14 Pa and a uniform frequency response ranging from 1 to 25 MHz. Its high sensitivity (1.6 μV / Pa) and compact size were achieved by capitalizing on the large electromechanical coupling coefficient of PVDF-TrFE and minimizing parasitic capacitance in a two-stage amplifier structure. The detection sensitivity of the newly designed sensor outperformed commercially available hydrophones with an equivalent sensing element area by a factor of 9. The sensor has been successfully integrated into a light scanning optoacoustic microscopy (OAM) system with a limited working space. Submicrometer resolution images were subsequently attained from living mice without employing signal averaging. The miniature sensor design can readily be integrated into various OAM systems and further facilitate multimodal imaging system implementations.

为提升光纤水听器拖曳线阵列的适装性，提出一种柔顺型光纤光栅水听器阵列。根据力学理论模型计算3种柔顺型光纤光栅水听器声压灵敏度，比较分析其影响因素，通过有限元仿真进行频响分析，研制了直径分别为10 mm、12 mm和16 mm的2元柔顺型光纤光栅水听器样阵，采用振动液柱法实验测试其灵敏度。实验结果表明：柔顺型光纤光栅水听器在200～800 Hz的频率范围内响应平坦，不同结构参数的水听器阵列平均声压灵敏度分别为−138.90 dB、−134.71 dB、−136.12 dB，验证了理论与仿真分析的正确性。按照本文的设计，通过进一步优化材料和结构参数，采用弱反射光纤光栅，可以构建数百阵元的一体化柔顺型水听器阵列。