飞秒激光加工微悬臂梁薄膜光纤声波传感器  

Femtosecond Laser Processing Micro-cantilever Thin-film Fiber Optic Acoustic Sensor

作　　者：郑怡雯 陈永璋 唐前浩 朱一新 于永芹 杜晨林 阮双琛 ZHENG Yiwen;CHEN Yongzhang;TANG Qianhao;ZHU Yixin;YU Yongqin;DU Chenlin;RUAN Shuangchen(Key Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Higher Education Institutes,Shenzhen Technology University,Shenzhen 518118,China;School of New Materials and New Energies,Shenzhen Technology University,Shenzhen 518118,China;Sino-German School of Intelligent Manufacturing,Shenzhen Technology University,Shenzhen 518118,China)

机构地区：[1]深圳技术大学广东省高校先进光学精密制造技术重点实验室,深圳518118 [2]深圳技术大学新材料与新能源学院,深圳518118 [3]深圳技术大学中德智能制造学院,深圳518118

出　　处：《光子学报》2023年第10期209-219,共11页Acta Photonica Sinica

基　　金：国家自然科学基金(No.61935014);深圳市科技项目(No.JCYJ20200109144012410);深圳技术大学研究生院与企业合作项目(No.XQHZ202201)。

摘　　要：设计并制作了一种光纤微悬臂梁传感器,由于悬臂梁在受迫振动过程中不会产生拉伸变形,与四周固定的圆形密闭薄膜相比,会产生更高的声波灵敏度。采用飞秒激光加工制作微悬臂梁薄膜光纤声波传感器,制备出长宽均为500μm,厚6μm的微悬臂梁结构。通过实验得到其反射光谱对比度为8.8 dB,自由光谱范围为7.72 nm,理论计算得光纤法布里-珀罗腔长为155.6μm。研究结果表明,该光纤声波传感器在2200 Hz处出现明显的共振峰,对应的声压灵敏度为414 mV/Pa,在300 Hz时有最大的灵敏度675 mV/Pa,与普通硅橡胶薄膜声波传感器相比灵敏度显著提高。理论计算硅橡胶微悬臂梁光纤声波传感器的一阶共振频率为198 Hz,与实验测得的共振频率较为接近。同时悬臂梁传感器的声压灵敏度可达675 mV/Pa,声压响应线性度为0.994。Compared with traditional capacitive or piezoelectric acoustic sensors,fiber optic acoustic sensors have unique advantages,such as passivity,high temperature resistance,corrosion resistance,light weight,wide frequency response,and immunity to electromagnetic interference.Optical fiber acoustic sensing technology can solve the measurement problems that traditional electronic acoustic sensing technology is not competent for.Acoustic sensors based on Extrinsic Fabry-Perot Interferometer(EFPI)are widely reported in practical applications owing to their simple principle,rapid-response,convenient manufacturing methods and good mechanical property.EFPI fiber acoustic sensors are usually composed of fiber end faces and acoustic sensing thin films,and their acoustic sensing characteristics are mainly determined by the thin films.A cantilever beam is a simple micro-mechanical sensing element that can detect small displacements or forces,typically manifested as a fixed protruding beam structure.Due to the advantages of simple structure,unlabeled detection,and high sensitivity,micro-cantilever beam sensors based on Micro-Electro Mechanical System(MEMS)technology have received a lot of attention in fields such as physics,chemistry,medicine,environment,materials,etc.Manufacturing micro-cantilever beam on the end face of fiber to form EFPI sensors,this structure can combine the common advantages of micro-cantilever beam and fiber sensing.Compared with traditional mechanical cantilever beam systems,fiber optic cantilever beam sensors have the advantages of simple structure,compact size,and high optical stability.Femtosecond laser,as a flexible,efficient,and non-contact machining tool,has important applications in the field of micro and nano structure manufacturing.Through laser irradiation,energy can be injected into the target material in a short period of time and concentrated near the focal point.Compared with other areas not irradiated by the laser,the target area is easy to achieve changes in surface properties.The use of f

关 键 词：光纤声波传感器 微悬臂梁 飞秒激光微加工 声压灵敏度 法布里-珀罗干涉仪 

分 类 号：TN253[电子电信—物理电子学]