光学学报, 2012, 32 (s1): s128003, 网络出版: 2013-01-05
微型法布里珀罗干涉剪应力传感器的设计及仿真
Design and Simulation of Miniature Shear Stress Sensor Based on Fabry-Perot Interference
摘要
针对微流体检测对高灵敏度和较大动态测量范围的要求,设计了一种由SU-8光刻胶一体合成的微型法布里珀罗(F-P)干涉剪应力传感器。结构兼具SU-8胶微尺寸材料优越的力学性能和法布里珀罗传感测量高精度和抗干扰性的优点,采用新型组合型浮动块设计,利用圆柱状底座提高对敏感膜形变的感知,提高传感器的结构响应。探讨了提高剪应力灵敏度和线性度的方法,通过CoventorWare软件数值模拟,确定模型的最优参数, 仿真计算得出在0~10 Pa范围内其灵敏度可以达到0.252 nm/Pa(光谱偏移/剪应力);相比较于传统的设计,在相同的作用下,组合型浮动块的机械位移量增加了约40.85%,提高了敏感元件的灵敏度。仿真结果表明,该模型由于采用一体化材料可以降低工作环境温度对传感器的影响,同时具备可靠的性能,为剪应力传感器设计的改进提出了可行的方案。
Abstract
To meet requirements for high sensitivity and wide dynamic range in detection of microfluid, a miniature shear stress sensor based on Fabry-Perot interference entirely utilizing SU-8 photoresist is presented. SU-8 photoresist has superior mechanical properties as a microstructure material. Meanwhile, accuracy and anti-interference performance of optical measurement based on Fabry-Perot interference theory are better than in traditional ways. The design concludes the above advantages. The model involves a novel design of floating element in combination type. The cylindrical lower part of floating element is designed so as to improve the perception of strain caused by the membrane′s deformation and the structural response. Improvement of sensitivity and linear response are also discussed. The optimum parameters are ascertained through a series of numerical simulation by CoventorWare softwave. Sensitivity of the model chosen is calculated up to 0.252 nm/Pa (spectrum offset/shear stress) within shear-stress range from 0 to 10 Pa. Compared with traditional designs, displacement of the combination-type floating element is raised by about 40.85%. The result states that this feasible design option can not only lower the influence of working environmental temperature, but also obtain reliable performance.
戴丽华, 王鸣, 戎华, 尤晶晶, 朱佳利. 微型法布里珀罗干涉剪应力传感器的设计及仿真[J]. 光学学报, 2012, 32(s1): s128003. Dai Lihua, Wang Ming, Rong Hua, You Jingjing, Zhu Jiali. Design and Simulation of Miniature Shear Stress Sensor Based on Fabry-Perot Interference[J]. Acta Optica Sinica, 2012, 32(s1): s128003.