基于奇偶函数法的绝对检测实验研究

针对平面干涉检测技术的检测精度受限于参考面面形精度的问题，提出使用基于奇偶函数的高精度绝对检测方法消除干涉系统中参考面面形误差的影响。对旋转角度误差与旋转偏心误差对绝对检测方法测量精度的影响进行了仿真分析。利用商用菲索干涉仪，设计和分析了绝对检测精度实验及重复性实验。仿真结果显示:旋转角度误差在达到0.13°时，测量误差PV值为0.000 1λ；旋转偏心误差达到3 pixel时，测量误差PV值为0.005λ。实验结果显示:测得实际样品的绝对检测精度PV₁₀值为0.041 5 λ，RMS值为0.008 7 λ，小于常规干涉检测所得结果；对同一平面两次独立的绝对检测结果进行点对点作差处理，从而获得残差图，其残差图PV₁₀值为0.004 λRMS值为0.000 5 λ。实验结果表明了该方法的高重复性和有效性。

Absolute test of flats based on even or odd functions

Aiming at the problem that detection accuracy of plane interferometry is limited by accuracy of reference surface shape, it is proposed to eliminate influence of reference surface error in interference system by using high precision absolute detection method based on parity function. Influences of rotation angle error and rotation eccentricity error on measurement accuracy of absolute detection method are simulated. Experiments and repetitive experiments of absolute detection accuracy are designed and analyzed by commercial Fischer interferometer. Simulation results show that measurement error PV value is 0.000 1λ when rotation angle error reaches 0.13 °; measurement error PV value is 0.005λ when rotation eccentricity error reaches 3 pixels. Experimental results show that absolute detection accuracy of actual sample PV₁₀ value is 0.041 5λ and RMS value is 0.008 7λ, which is smaller than that of conventional interference detection. Point to point processing is done for two independent absolute detection results in the same plane, in this way residual graph is obtained with PV₁₀ value is 0.004 λ and RMS value is 0.000 5 λ. Experimental results show that this method is highly reproducible and effective.