Share Email Print

Proceedings Paper

Extended depth of focus intra-ocular lens: a solution for presbyopia and astigmatism
Author(s): Alex Zlotnik; Ido Raveh; Shai Ben Yaish; Oren Yehezkel; Michael Belkin; Zeev Zalevsky
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Purpose: Subjects after cataract removal and intra-ocular lens (IOL) implantation lose their accommodation capability and are left with a monofocal visual system. The IOL refraction and the precision of the surgery determine the focal distance and amount of astigmatic aberrations. We present a design, simulations and experimental bench testing of a novel, non-diffractive, non-multifocal, extended depth of focus (EDOF) technology incorporated into an IOL that allows the subject to have astigmatic and chromatic aberrations-free continuous focusing ability from 35cm to infinity as well as increased tolerance to IOL decentration. Methods: The EDOF element was engraved on a surface of a monofocal rigid IOL as a series of shallow (less than one micron deep) concentric grooves around the optical axis. These grooves create an interference pattern extending the focus from a point to a length of about one mm providing a depth of focus of 3.00D (D stands for Diopters) with negligible loss of energy at any point of the focus while significantly reducing the astigmatic aberration of the eye and that generated during the IOL implantation. The EDOF IOL was tested on an optical bench simulating the eye model. In the experimental testing we have explored the characteristics of the obtained EDOF capability, the tolerance to astigmatic aberrations and decentration. Results: The performance of the proposed IOL was tested for pupil diameters of 2 to 5mm and for various spectral illuminations. The MTF charts demonstrate uniform performance of the lens for up to 3.00D at various illumination wavelengths and pupil diameters while preserving a continuous contrast of above 25% for spatial frequencies of up to 25 cycles/mm. Capability of correcting astigmatism of up to 1.00D was measured. Conclusions: The proposed EDOF IOL technology was tested by numerical simulations as well as experimentally characterized on an optical bench. The new lens is capable of solving presbyopia and astigmatism simultaneously by providing focus extension of 3.00D under various illumination conditions, wavelengths and pupil diameters of the implanted lens without loss of energy at any of the relevant distances.

Paper Details

Date Published: 2 March 2010
PDF: 6 pages
Proc. SPIE 7550, Ophthalmic Technologies XX, 75500A (2 March 2010); doi: 10.1117/12.846682
Show Author Affiliations
Alex Zlotnik, Xceed Imaging Ltd. (Israel)
Ido Raveh, Xceed Imaging Ltd. (Israel)
Shai Ben Yaish, Xceed Imaging Ltd. (Israel)
Oren Yehezkel, Xceed Imaging Ltd. (Israel)
Michael Belkin, Goldshleger Eye Research Institute, Tel-Aviv Univ. (Israel)
Zeev Zalevsky, Bar-Ilan Univ. (Israel)

Published in SPIE Proceedings Vol. 7550:
Ophthalmic Technologies XX
Fabrice Manns; Per G. Söderberg; Arthur Ho, Editor(s)

© SPIE. Terms of Use
Back to Top