[Characteristic analysis of modulation transfer function curve of retina-brain system]

This study was aimed to find some parameters for characterizing the modulation transfer function (MTF) specific to diagnosing eye diseases. Least-square regression method was used for MTF curve (at logarithmic axis) fitting with quadratic equation so as or cubic equation to obtain the desired parameters. The data of normal and some eye diseases were fitted by quadratic and cubic equations. Three or four parameters were obtained from the curve fitting. The fitting curves were also expressed with figures along with the original data. For symmetric MTF, parameters k1, k2 and k3 were used to characterize the eye diseases. For asymmetric MTF, an additional parameter k4 was used to show the different injures of frequency channels.