分析了彩色图象的半色调算法，包括加网角度的调整、阈值矩阵的选取及网点形状的设计，并在激光印字机上进行了模拟，说明算法是正确的。在此基础上，引入二维ＦＦＴ技术，对半色调误差图象的质量进行了分析研究。分析评价方法可以适用于其他半色调算法。 The halftone algorithm of color image is analyzed, including the adjustment of screen angle, the selection of threshold matrix and the design of dot shape. The simulation is carried out on a laser printer, which shows that the algorithm is correct. On this basis, the introduction of two-dimensional FFT technology, the quality of halftone error image analysis. Analytical evaluation methods can be applied to other halftoning algorithms.