Measurement of the Modulation Transfer Function of Infrared Imaging System by Modified Slant Edge Method

The performance of a staring infrared imaging system can be characterized based on estimating themodulation transfer function (MTF). The slant edge method is a widely used MTF estimation method,which can effectively solve the aliasing problem caused by the discrete undersampling of the infrared focalplane array. However, the traditional slant edge method has some limitations such as the low precisionof the edge angle extraction and using the approximate function to fit the edge spread function (ESF),which affects the accuracy of the MTF estimation. In this paper, we propose a modified slant edge method,including an edge angle extraction method that can improve the precision of the edge angle extractionand an ESF fitting algorithm which is based on the transfer function model of the imaging system, toenhance the accuracy of the MTF estimation. This modified slant edge method presents higher estimationaccuracy and better immunity to noise and edge angle than other traditional methods, which is demonstratedby the simulation and application experiments operated in our study. KCI Citation Count: 14