基于亚波长光栅的柔性多层PDMS波导振动传感器  

Flexible Multilayered PDMS Optical Waveguide Vibration Sensors Based on Subwavelength Gratings

作　　者：王劭鹤 林伟强 吴佩瑾 李晨 叶志成[2] Wang Shaohe;Lin Weiqiang;Wu Peijin;Li Chen;Ye Zhicheng(State Grid Zhejiang Electric Power Research Institute,Hangzhou 310014,Zhejiang,China;Department of Electronic Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;School of Physics and Astronomy,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]国网浙江省电力有限公司电力科学研究院,浙江杭州310014 [2]上海交通大学电子工程系,上海200240 [3]上海交通大学物理与天文学院,上海200240

出　　处：《光学学报》2024年第14期316-325,共10页Acta Optica Sinica

基　　金：国网浙江省电力有限公司科技项目(5211DS220007)。

摘　　要：提出一种基于亚波长光栅的柔性聚二甲基硅氧烷(PDMS)多层PTP(PDMS-TiO_(2)-PDMS)结构的传感器。该器件通过感知外界振动引起的光栅周期变化所导致的波导共振波长变化实现传感。利用电磁波有限元方法优化光栅结构以获得最深的共振谷和最高的反射峰。运用模板复制、镀膜和复合封装制备工艺完成PTP结构制备,进而完成传感器制备。静态实验结果表明,此传感器对温湿度不敏感。在杨氏模量为1.70~2.46 MPa的情况下,应变灵敏度为12.34 nm/%,应变量程为-3.15%~8.10%,应力量程为-79.48~161.90 kPa,理论可测振动加速度量程为-362.22~890.69 m/s^(2)。在断路器设备上的振动测试结果证明了该传感器工作原理的有效性,为新型光学式振动传感器提供了切实可行的新方案。Objective Vibration sensors are widely used for security monitor in various industries, including industrial, electric power, bridges, and transportation. Traditional vibration sensors such as piezoelectric and piezoresistive types offer high sensitivity, but they are susceptible to electromagnetic interference and require a rigid installation environment. In contrast, optical vibration sensing is gaining attention due to its immunity to electromagnetic interference, flexibility in arrangement, and suitability for remote monitoring. Fiber-typed Bragg-grating is a typical device among optical vibration sensing techniques, however, the strong mutual coupling among temperature, humidity, and vibration signals hinders their applicability. In response to these challenges, we propose a flexible multilayered PDMS-TiO_(2)-PDMS(PTP) optical waveguide vibration sensor based on subwavelength gratings. The sensing mechanism is achieved by measuring the waveguide mode resonance wavelength shifts corresponding to the change of grating pitch induced by vibration. This sensor demonstrates excellent stability, high sensitivity, and high resistance to temperature and humidity, presenting a promising avenue for advancing optical vibration sensing applications.Methods Theoretically, we deduce the vibration sensing principle based on inertial characteristics, elucidating the relationship between the reflective peak wavelengths and the period of the grating. The equivalent refractive index of the grating layer based on guiding mode resonance is obtained. By leveraging guiding mode resonance, we derive the waveguide mode resonant reflective peak wavelength corresponding to vibration acceleration. Subsequently, optical vibration sensors based on PTP grating waveguide structure are designed. Along the direction perpendicular to the grating,one end of the PTP structure is fixed on a frame, and the other end is connected to a mass block and a spring, where the spring is fixed on the frame. Finite element method(FEM) is employed to optimize

关 键 词：传感器 亚波长光栅 振动传感器 波导共振 柔性光学膜 

分 类 号：O439[机械工程—光学工程]