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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.
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