Zhang Yongfeng, Xian Hao
Opt Lett. 2020 Mar 1;45(5):1051-1054. doi: 10.1364/OL.385262.
A dispersed fringe sensor (DFS) is a promising approach for sensing the large-scale piston error for segmented mirror systems. In this Letter, a novel method, to the best of our knowledge, for piston sensing based on a digital dispersed fringe (DDF), which is generated by wavelength tuning, is introduced. By continuously changing the wavelength of light passing through the sensor, a collection of far-field spot arrays can be acquired, which are used to construct the DDF with steps of accumulation and stacking in sequence for each inter-segment region. A correlation-based method is applied to extract the encoded piston information from the DDF. The method greatly eases the demanding hardware requirement in traditional DFS and shows high efficiency for the reason that it could simultaneously measure all of the relative piston settings; in addition, it exhibits strong robustness to noise.
一种离散条纹传感器（DFS）是用于检测分段镜系统中大规模活塞误差的一种很有前景的方法。在本信函中，据我们所知，介绍了一种基于数字离散条纹（DDF）的新型活塞传感方法，该条纹由波长调谐产生。通过连续改变穿过传感器的光的波长，可以获取一系列远场光斑阵列，这些光斑阵列用于为每个段间区域按顺序进行累积和堆叠步骤来构建DDF。应用基于相关性的方法从DDF中提取编码的活塞信息。该方法极大地减轻了传统DFS中对硬件的苛刻要求，并且由于它可以同时测量所有相对活塞设置而显示出高效率；此外，它对噪声具有很强的鲁棒性。
