基于刃边法计算大气调制传递函数

调制传递函数MTF（ModulationTransferFunction）是描述成像系统空间频率响应特性的重要方法之一。本文为了获得大气调制传递函数，主要运用倾斜刃边法测量灰霍大气对光学成像系统的空间频率响应。详细阐述了倾斜刃边法测量MTF的基本原理，其中边缘扩展函数ESF和线扩展函数LSF是计算图像MTF的理论基础。通过对采集到的灰霾图像进行数据采样、插值和拟合得到ESF和LSF，LSF经离散采样并截取有效长度，进行傅里叶变换得到图像MTF。最终对比演算多组灰霾图像的MTF，可得到大气的调制传递函数。

Study of Atmospheric Modulation Transfer Function Based on Edge Method

The modulation transfer function （MTF） is one of the important methods,which describe the spatial frequency response characteristics of the imaging system.In this paper, in order to obtain atmospheric modulation transfer function,the Slanted-Edge method was mainly used to measuring the ash haze weather on spatial frequency response of the imaging System.It details the basic principle of measuring MTF through the Slanted-Edge method,in which edge spread function （ESF） and line spread function （LSF） are the theoretical basis of calculating image MTF.Through studying the problems of the sampling,interpolating and fitting of the haze image,the ESF and LSF were obtained.With the help of discrete sampling of LSF and calculating its Fourier transform,the MTF was accomplished.Finally, the tmospheric modulation tansfer function was obtained by comparing and calculating the multiple sets of haze image MTF.