采用热像系统MTF(调制传递函数)建立虚拟热像仪的研究

Research on Developing Virtual IR Imager by MTF of Real System

热像仪作为一种成像系统,其功能是将接收到的二维空间分布的景物红外辐射转换成可视图像再现景物的红外图像。利用光学傅立叶分析的方法可以把热成像系统看作线性滤波器,并建立热成像系统的静态性能模型。利用热成像系统静态性能参数MTF(调制传递函数)的实验室测试数据作为幅频特性,用设计数字滤波器的频率样本法构造仿真热像仪MTF的二维图像滤波器,以此为基础可以建立用计算机仿真热像仪空间分辨特性的模拟环境。

As an imaging system, the main purpose of the thermal imager is to transform the infrared radiation of scenery into visual infrared image. The thermal imaging system can be regard as a linear filter and its static performance model can be established by optical Fourier analytical method. Based on the data of the MTF （Modulation Transfer Function）, as a parameter of static performance model of thermal imaging, we designed a digital filter by frequency sampling method, and develop this digital filter into two-dimensional image filter to simulate the spatial resolution characteristics of the thermal imager by computer technology.