集成光波导微应力传感器研究

Research on Integrated Optical Waveguide Microstress Sensor

在外力作用下,LiNbO3晶体内部产生微应力,引起波导的长度和折射率发生变化,从而使光波导中的光产生相位变化。基于此研究了一种Mach-Zehnder干涉仪型悬臂梁式光波导微应力传感器,分析了它的基本工作原理,并计算出施加外力与相位差之间的线性关系,确定了微应力传感器的灵敏度和量程,最后分析了它的弯曲损耗。

LiNbO3 crystal interior has microstress under the load, which can cause a change of waveguide length and refractive index, thus the optical phase in the waveguides will change. Based on this phenomenon, the research concerns on a Mach-Zehnder interferometer waveguide microstress sensor of cantilever beam structure, its basic principle is introduced, and the linear relation between stress and phase difference is also formulated, the sensitivity and measuring range are determined, at last the bending loss is analyzed.