Modulation transfer function and pupil size in multifocal and monofocal intraocular lenses in vitro

With a zonal progressive multifocal IOL, the pupil size effected a trade-off between the far and near MTFs: The near MTF increased at the expense of the far MTF at large pupil sizes (effective pupil diameter >3.4 mm). To enhance near vision with a multifocal IOL, the desirable effective pupil diameter should be 3.4 mm or larger.