Apodization model of the Stiles-Crawford effect.

Several implication of Metcalf's apodization model of the Stiles-Crawford effect are presented in this paper. Metcalf showed that there should be a slight smearing of the point-spread function due to the Stiles-Crawford effect. It will be shown that this smearing is approximately equal to the size of a foveal cone. As an abvious consequence of this smearing, there is a decrement in the dodulation transfer function for high spatial frequecies. But unexpectedly, there is an increment in the MTF for low spatial frequencies.