提出了一些新的基于数字处理技术的莫尔信号细分及辨向方法。单光栅副莫尔条纹采用差值细分方法;双光栅副莫尔条纹采用乘积细分法。将信号进行区间划来实现辨向。实验采用DSP器件内置的高速A/D模块实现数/模转换,利用DSP专用指令实现信号的滤波、细分和辨向。实验结果表明,单光栅副和多光栅副的细分精度分别为3″和0.3″。
Based on the digital processing, some new methods were put forward for subdivision and direction judgment of Moiré fringes. Moiré fringes of one couple of gratings adopted means of difference subdivision, while Moiré fringes of double couple of gratings made use of the method of product subdivision. Interval division of signals was carried out to judge direction. This experiment adopted high-speed built-in A/D modules of DSP devices to realize analog/digital conversion and DSP specialized instruction to realize digital filtering, subdivision and direction judgment. The results show that one couple of gratings and double couple of gratings are 3arcsec and 0.3arcsec respectively.