基于Catmull-Rom插值算法光栅分辨率测试系统改进

为了减小探测器采集及软件处理导致的系统误差，提高光栅分辨率检测精度，利用半宽度法设计了一套满足李特洛条件的阶梯光栅分辨率检测系统。搭建了系统的光路，介绍了提高分辨率的方法，重点分析了探测器像元尺寸对系统分辨率测试精度的影响，提出了在LabVIEW软件中如何根据离散光谱信号并利用Catmull-Rom插值构造出连续光谱，提高半宽度法检测的精度。实验结果表明，在高分辨率测试系统中，通过软件算法对离散信号进行拟合分析，能有效的解决由像元尺寸造成的系统误差。

The Improvement of Grating Resolution Testting System Based on Catmull-Rom Interpolation Algorithm

In order to reduce the system error caused by detector acquiring and software processing,and improve the accuracy of echelon grating resolution,a resolution detection system which satisfied Littrow condition was designed by using the half wave width method. The optical structure of the detection system was built and the improved detection method was introduced. Then the grating resolution influenced by detector pixel size was analyzed. By using Catmull-Rom interpolation algorithm to fit a continuous spectral curve,the accuracy of half wave width according to the discrete spectrum was improved in LabVIEW. The experimental result also showed that the system error caused by pixel size can be effectively reduced by fitting analysis of discrete signal in the high resolution testing system.