Abstract

To implant intraocular lenses (IOL) is a common technique in cataract surgery. At the beginning, only monofocal lenses were used, but lately also different types of multifocal IOLs are available¹. In the evaluation of postoperatory visual performance, contrast tests, such as CSF, are replacing visual acuity, since contrast is recognized as a key parameter in both optical quality (Modulation Transfer Function, MTF) and visual performance (Contrast Sensitivity Function, CSF). Although the CSF contains information about the optical quality of the eye, it strongly depends also on retinal, neural and even psychological factors. MTF estimates of IOLs are usually available by both designer computations and optical bench measurements. However the real MTF of the implanted eye could largely differ from these previous estimates, because of many factors such as subject variability, lens decentering, shifts, tilts, etc. In consequence a direct measurement of the MTF is necessary, if one really wants to know the resulting optical performance of the implanted eye.

© 1992 Optical Society of America