Modulation transfer function (MTF)

in testing radionuclide detectors or radiographic systems, the efficiency, at each spatial frequency, of reproducing the variation (contrast) in the object density or signal in the image; it is an expression of spatial resolution and is used to evaluate imaging systems and their components; the integral of the line spread function; also known as the frequency response function or contrast transmission function; usually given as a plot of percentage amplitude response versus frequency in cycles per millimeter.