摘要
为探索白光干涉仪在测量矩形台阶时的蝠翼效应误差,建立白光干涉虚拟测量模型。在模型中,考虑白光光源带宽和干涉物镜数值孔径以及圆孔衍射模型的影响,分析蝠翼效应与真实台阶高度、光源中心波长之间的关系。模拟结果表明当台阶高度差是λ_(0)/4的奇数倍时会出现蝠翼效应,且越接近λ_(0)/4的奇数倍,蝠翼效应越显著。关于对蝠翼误差的补偿,分别采用中值滤波和均值滤波两种方式对含有蝠翼效应的测量结果进行修正,并利用台阶高度、台阶与轮廓中线围成的面积两种评价参数对比补偿效果,结果表明中值滤波的修正结果优于均值滤波。
To solve the batwing effect when measuring rectangular steps,a white-light interferometry model is established.In this model,considering the influence of bandwidth,numerical aperture and diffraction by circular aperture,the relationship between step height difference,center wavelength and the batwing effect is analyzed.The simulation results show that the batwing effect will appear when the height difference is an odd multiple of λ_(0)/4,and batwing effect is most pronounced when the height difference is closer to the odd times of λ_(0)/4.To compensate the batwing effect,median filter and mean filter are used to correct the measurement results.Then the compensation effects are compared by two evaluation parameters:the height difference,and the area enclosed by the step contour with its centerline.The results show that the correction result of median filter is better than mean filter.
作者
李萍
闫英
周平
LI Ping;YAN Ying;ZHOU Ping(Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education,Dalian University of Technology,Dalian 116024,China)
出处
《中国测试》
CAS
北大核心
2022年第1期1-8,共8页
China Measurement & Test
基金
国家自然科学基金(51975094,51875078,51991372)
中央高校基本科研业务费(DUT20LAB108,DUT20ZD216)。
关键词
白光干涉仪
蝠翼效应
衍射光学
光栅
white-light interferometer
batwing effect
diffractive optic
grating