Modulation Transfer Function Measurement Using Three- and Four-bar Targets

Modulation-transfer-function (MTF) measurement often involves the use of three- and four-bar resolution targets. In the conversion of three- and four-bar image data to MTF, biased results can occur when we use series-expansion techniques appropriate for square-wave targets of infinite extent. For systems where the image data are digitally recorded, a convenient and accurate conversion of bar-target data to MTF can be performed using a Fourier-domain method.