光压加速度计光斑位置检测技术研究

Study on Spot Detection Technology of Ligtht Force Accelerometer

光压加速度计(LFA)是一种新型光学惯性传感器,LFA系统分为微球悬浮与捕获、位置检测、光学闭环与加速度值输出三个模块,其中位置检测的精度对整个LFA系统的性能起着至关重要的作用。简述了LFA的工作原理以及光斑获取方法,提出了一种小角度折射光斑获取方法,有效地减小了由于微球表面畸形所造成的检测误差;在光斑位置检测方面,采用四象限探测器(QD)作为光斑位置检测元件,在经典几何近似法的基础上,引入了Boltzmann函数模型,提出了一种新型的协同拟合算法,有效地减小了检测误差。实验结果表明,新型的协同拟合算法相比单一的几何近似法,检测误差减小约56%。

As a new type of optical inertial sensor,LFA system consists of three modules of microsphere suspension and capture,position detection and output of optical closed-loop and acceleration.The accuracy of the position detection effects a lot in the whole LFA system.In this paper,the working principles of LFA and spot acquisition method were introduced,based on which,a small angle refraction spot acquisition method was proposed to effectively reduce the detection error caused by the malformation of microarray surface.For the detection of spot positions,using QD as the detection element and based on the classical geometric approximation method,a new cooperative fitting algorithm was proposed by introducing Boltzmann function model.Experimental results show that,compared with the single geometric approximation method,the new cooperative covariance algorithm reduces the detection error by about 56%.