Assessing the optical performance of multifocal (diffractive) intraocular lenses
Timo Eppig1, Katja Scholz, Achim Langenbucher
1Medical Optics, Department of Medical Physics, University of Erlangen-Nuremberg, Erlangen, Germany. timo.eppig@imp.uni-erlangen.de
Summary
This study developed a new test setup to evaluate multifocal intraocular lenses (IOLs). The system effectively assessed how spherical aberration in model corneas impacts IOL optical performance, particularly the modulation transfer function (MTF).
Area of Science:
- Ophthalmology
- Optical Engineering
- Biomedical Optics
Background:
- Assessing multifocal intraocular lenses (IOLs) is complex due to multiple focal points.
- Standardized optical performance evaluation is crucial for IOLs, adhering to ISO 11979.
Purpose of the Study:
- Develop a robust test setup for evaluating IOL optical properties.
- Measure the point spread function and modulation transfer function (MTF) of multifocal IOLs.
Main Methods:
- Constructed a specialized test apparatus for IOL optical measurements.
- Utilized two model corneas: a diffraction-limited model and an aspheric model with spherical aberration.
- Tested three distinct multifocal IOL models.
Main Results:
- Spherical aberration significantly influenced the MTF of tested IOLs differently.
- Bispheric IOLs showed MTF degradation with the aspheric model cornea.
- A prolate aspheric IOL (Tecnis) demonstrated improved MTF with the aspheric model.
Conclusions:
- The developed measurement system reliably evaluated multifocal IOLs.
- An aspheric model cornea is suitable for testing both monofocal and aspheric multifocal IOLs.
- The system effectively analyzes the impact of spherical aberration on IOL performance.
