A method of automatically recognizing CTF image and calculating value

MTF is one of the important indexes of optical system. It is a common method to test the CTF of optical system by target method and then retrieve the MTF of optical system. In traditional methods, the position and angle of the target need to be accurately aligned. It needs precise tooling and tedious alignment work. This paper proposes a method based on centerline extraction to automatically recognize the CTF image and calculate the value without alignment. There are few requirements for tooling and alignment. The measured data show that the method is feasible and effective.