【作者】 鲁平； 王顺； 张亮； 刘理； 廖浩；

【Author】 Lu Ping;Wang Shun;Zhang Liang;Liu Li;Liao Hao;School of Optical and Electronic Information and National Engineering Laboratory for Next Generation Internet Access System, Huazhong University of Science and Technology;

【机构】 华中科技大学光学与电子信息学院下一代互联网接入系统国家工程实验室；

【摘要】 近年来,光纤声传感技术,已经被广泛应用于人们的生产生活中,例如地震波检测、光纤水听器、无损探伤、工业过程化控制、结构健康监测等等。光纤声传感技术不但面向声波检测与分析技术的应用需求,而且结合了光纤传感的巨大优势,具有十分重要的研究意义。对低频甚至是次声波段的声波信号进行高灵敏度地探测,在一些特殊领域具有十分重要的意义。例如在自然灾害预警、医疗诊断、光纤水听器、甚至战场上,高灵敏度光纤声传感技术都展现出巨大的潜力。因此,高灵敏度光纤声传感技术逐渐成为一个十分有趣的研究热点。目前的高灵敏度声传感技术主要可分为电容式、压电式和光纤式三大类。前两者作为传统声传感技术的代表,技术较为成熟,并且被广泛应用。光纤式高灵敏度声传感技术,作为一种新兴的技术代表,虽然尚未产业化,但相对前两种而言具有诸多优势:成本低、高信噪比、大动态范围,能抗电磁干扰、长距离传输、分布式测量、能工作于高温高压环境中等等。因此,高灵敏度光纤声传感技术,将会是未来该领域发展的必然趋势。为了实现高灵敏度低频的光纤声传感应用,本次报告将提出一系列新型光纤声传感方法。它们分别基于强度、拍频、干涉等光学原理,具有尺寸小、成本低、易实现等优势。例如能实现可听频段(20Hz-20k Hz)高灵敏度(2.63 m W/Pa)强度探测的非标准光纤耦合型声传感器、具有高稳定性声压探测范围在0-20Pa的基于碳纳米管被动锁模多纵模光纤激光声压传感器、在90-500Hz频率范围内灵敏度高达-118d B迈克尔逊干涉型传声器等。此外,基于光纤外腔式法珀干涉原理,本文实现了高精度(121m V/Pa)的次声(1-20Hz)传感器;利用光学游标原理和波分复用技术,本文还实现了灵敏度达45.3rad/Pa的准分布式声传感应用。更多还原

【Abstract】 In recent years, our research group has proposed a series of high-sensitivity fiber opticacoustic sensor(FOAS) technology solutions. Such as a kind of differential intensity modulation method based on non-standard fiber optic coupler, whose intensity sensitivity can be 2.63 m W/Pa. This sensor has good response in the range of20Hz-20 k Hz; Including another novel solution based on passively mode-locked multi-longitudinal-mode fiber laser for sound pressure sensing, a highly acoustic pressure sensitivity of 147.2Hz/Pa is achieved at the sound pressure range 0-20Pa; Besides,a MI based low-frequency FOAS employing plastic diaphragmis alsoresearched, whose sensitivity can be-118 d B at 90-500 Hz. Furthermore, specially for infrasound sensing, EFPI sensors based on composite film or polymer film are also fabricated. And experimental results show high sensitivity-138.3 d B re 1 V/μPa @1 Hz and infrasound working frequency 1-20 Hz. In addition, a quasi-distributed fiber optic acoustic sensing scheme based on optical vernier effect principle is also raised, the sensitivity is as high as 45.3rad/Pa, and employing the WDM technology, quasi-distributed fiber optic acoustic sensing application can be realized. In short, our research group has implemented a lot of highly sensitive fiber acoustic sensing applications in terms of intensity, beat frequency, phase, and so on.更多还原