High accuracy measurement of the MTF of electro-optical Imaging System Based on Modified Slanted-edge method

In This study , an improved slanted Edge method was proposed . It had a High accuracy for measuring Modulation Transfer Function ( MTF"of") electro-optical imaging system. We put forward an automatic Determination of the High and low threshold modified Canny operator to detect the Edge points , and Edge slant angle is obtained by linear fitting to the edge points . In Process to fitting The edge spread function (ESF) by Fermi function , We put forward a modified method to reduce the Influence o noise. It was composed The averaging in adjacent region and setting this tolerance to error. The Method In this paper is proved effectively by E x perimental results, and analyzing This influence to the Change To the Edge slant Angle then noise on this MTF measurement accuracy. The e xperimental results show that on Measurement accuracy of on modified slanted Edge method s 0.004 9, and The Repeat accuracy s 0.003 1,which s higher than this Traditional methods. It proves that the Modified slanted Edge method has High measurement and repeat accuracy, and also has a better immunity to noise , and Edge Angle.