边缘扩展函数的微商是线扩展函数,而线扩展函数的富里哀变换即系统的传递函数。本文介绍了测量边缘扩展函数值后,计算系统传递函数的B.Tatian及R.Barakat方法及我们建议采用的方法。用边缘扩展函数测量热象仪的调制传递函数,方法简便,容易实现,同时可测量最小可探测温差。本文对一实测结果进行了计算,给出了这一热象仪调制传递函数曲线。 The derivative of the edge expansion function is a linear expansion function, while the line expansion function is the system’s transfer function. This article describes the B.Tatian and R.Barakat methods for calculating the transfer function of a system after measuring the value of the edge expansion function and the method we recommend. Using the edge expansion function to measure the modulation transfer function of the thermal imager, the method is simple and easy to implement, and the minimum detectable temperature difference can be measured at the same time. In this paper, an actual measurement result is calculated, and the thermogram modulation transfer function curve is given.