介绍Auto focus的文章，主要介绍了对焦技术，探测技术；包括频域分析、目标函数、目标函数效能验证、影像评估效能之因素、高斯低通滤波器参数的选取、自动对焦技术；以及相关实验结果与分析。-Introduction Auto focus of the article introduces the focus technology, detection technology including frequency domain analysis, the objective function,