MTF testing device for photoelectric imaging system based on slit tilting method

Modulation transfer function (MTF) is one of significant parameters for designing and evaluating an photoelectric imaging system. As the traditional MTF measurement algorithm cannot meet the need of discrete sampling characteristics for photoelectric system, an automatic interpolaton and sub-pixel matching algorithm based on slit tilting method is proposed.Through the least-square analysis of line spread function (LSF),the tilting angle can be automatically calculated, and interpolaton of sub-pixel data can be precisely reconstructed. The noise of oscillation can be effectively restrained by a hanning window function. A device composed of target generator system, off-axis reflective collimator, mechanical adjustment, electrical control system, video acquisition module and comprehensive software was setup. The validity of the method was verified by experiments. The repeatability reached 0.007.