反射面形状对光纤位移传感器光强调制特性的影响

Influence of Reflector Shape on the Intensity Modulation of Fiber Optical Distance Sensors

为了分析反射面形状对单模光纤照射的光纤位移传感器光强调制特性的影响,建立了反射面不为平面时的光强调制特性函数模型.该模型基于单模光纤出射光场为修正近似高斯分布假设,通过引入反射面形状因子,分析了反射面形状因子对光强调制特性的影响规律.仿真结果表明,随着凹形反射面曲率半径值的增大,传感器特性曲线的前坡无显著变化,而后坡灵敏度增大,线性范围减小;随着凸形反射面曲率半径值的增大,传感器特性曲线的前坡仍无显著变化,而后坡灵敏度减小,线性范围增大;当曲率半径增大的一定值时,反射面的非平面性影响较小,其作用趋近于平面.

To study the impact of reflector shape on the performance of a reflective intensity-modulated fiber optical distance sensor with single mode illumination,a theoretical model was established based on the assumption that the single mode fiber output light field is the modified approximate Gaussian distribution.By introducing the reflector shape factor,the influence discipline of the reflector shape factor on the intensity modulation characteristics was analyzed.Simulation results indicate that for concave reflector,as the radius of curvature increases,the sensitivity of the back slope becomes larger and the linear range of the back slope becomes smaller while those of the front slope remain almost unchanged.However,for convex reflector,as the radius of curvature increases,the sensitivity of the back slope becomes smaller and the linear range of the back slope becomes larger while those of the front slope also remain almost unchanged.As the radius of curvature increases,the effect of the nonplanar reflector becomes weaker until it disappears.