基于衍射微透镜的光学加速度传感器设计

Design of Optical Acceleration Sensor Based on Diffractive Micro Lens

提出了一种基于菲涅耳衍射微透镜的新型光学加速度传感器,它能够解决导航系统中惯性传感器普遍存在的抗电磁干扰和电磁冲击能力差等缺陷。其传感原理是把一个反光膜平行地置于衍射微透镜的后方,加速度的变化会改变反光膜的位置,根据微透镜前方会聚点处光强的变化,感知加速度的大小。介绍了传感器及其动力学系统的工作原理,并对衍射微透镜和动力学系统的微弹性机械结构进行了设计和加工,最后对传感器的性能和误差进行了分析。原理验证性实验的结果表明这种新型光学加速度传感器的原理正确,并且结构简单,灵敏度高。

A novel optical acceleration sensor based on a Fresnel diffractive micro lens is presented. It can effectively solve the low immunity of inertial sensors widely used in navigation system towards electro magnetic interference and electro magnetic pulse. A reflecting membrane is parallelly located behind the diffractive micro lens and its displacement is determined by the acceleration. Acceleration is calculated by measuring variational light intensity at the frontal focal point of the lens. The principles of the sensor and its dynamic system are described, and both the diffractive micro lens and the micro spring-mechanical structure of the dynamic system were designed and fabricated. Moreover, the performance and error of the sensor were analyzed. The results of proof-of-principle experiments indicate that the principle of the novel sensor is correct and the sensor has merits of simple structure and high sensitivity.