Method for testing modulation transfer function of photoelectric theodolite located at external field

An embodiment of the invention discloses a method for carrying out inversion calculation on a modulation transfer function of a photoelectric theodolite located at an external field on the basis of amultiple linear regression model. The method comprises the following steps: acquiring dependent variables and independent variables which are used for establishing the multiple linear regression modelby testing a target simulation source in a laboratory, and calculating to obtain regression coefficients and constants in the multiple linear regression model by using the least square method; and inan external field environment, taking an image feature definition vector of an image acquired by the photoelectric theodolite as an independent variable in the multiple linear regression model, substituting the image feature definition vector into the multiple linear regression model and calculating to obtain the modulation transfer function in the external field environment. By the embodiment ofthe invention, the problem