Imaging quality of multifocal intraocular lenses: automated assessment setup

Purpose: A new technique for the assessment of the optical quality of multifocal intraocular lenses (MIOLs) under monochromatic and polychromatic illumination is presented. Methods: The system provides, in a totally automated procedure, the modulation transfer function (MTF) of the lens under test for different axial positions of the object. The artificial eye admits different artificial corneas, to optimise the axial resolution in the sampling of the MTF of the MIOL under test, and different pupils, to test the dependence of the optical performance of the MIOL on the eye pupil diameter. Results: The performance and sensitivity of the apparatus is tested with different commercial MIOLs. The through-focus MTF for a refractive MIOL was measured at different moments during the process of hydration of a hydrophilic lens. Next, to show the performance of our proposal, two commercial refractive and diffractive MIOLs were evaluated. Conclusions: We have designed a precise and robust optical method for testing MIOLs in vitro. The proposed method represents a valuable technical improvement to make the procedure of MIOL evaluation more versatile, efficient and trustworthy.