Purchase this article with an account.
Walter Torres, Alejandro Mira-Agudelo, John Fredy Barrera, Andrzej Kolodziejczyk; Optimization of the light sword optical element (LSOE) for presbyopia correction. Invest. Ophthalmol. Vis. Sci. 2019;60(9):3724. doi: https://doi.org/.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
the LSOE has been previously evaluated as presbyopia corrector, showing a good performance in near and intermediate vision but a lower correction quality for far vision. The aim of this work is to study some modifications of the LSOE to obtain a suitable profile that provides a better performance for far vision, keeping a good behavior for the other optical powers
the proposed modifications of the LSOE consist of assigning a window of the optical power 0 D designed for far vision and rescaling the original profile in the remaining area of the element. Angular and circular windows shapes are proposed and 8 modified LSOE profiles are tested: 4 for angular windows with angles β=30°, 45°, 60° and 90°, and 4 with circular windows of radii ρ=0.25R, 0.3R, 0.36R and 0.4R (R is the radius of the complete profile: 6mm). Defocus curves of Strehl ratio values were used to simulate the performance of the redesigned LSOEs. A monocular visual simulator was used for objective and subjective testing of the modified LSOEs. For objective test, correlation coefficient and Michelson’s contrast defocus curves were determined using a Snellen optotype and an USAF test respectively, both imaged by the modified profiles. Finally, 3 LSOE profiles (β=45°, 90° and ρ=0.36R) were subjectively tested providing monocular visual acuity (VA) and contrast sensitivity (CS) defocus curves for 6 subjects (3 women, 3 men): age 25 to 39; average refraction −0.46±1.30 D and average astigmatism −0,34±0,17 D. Presbyopia was mimicked by using 1% Tropicamide drops. The tested defocus range was [-4, +1] D
the computational simulations and objective experiments confirmed a better performance of the modified LSOE for far vision (defocus of 0 D). VA defocus curves also show a clear improvement provided by the tested LSOEs at 0 D. The difference between the naked eye and the corrected eye at 0 D was (in logMAR) 0.24, 0.14 and 0.08 for the original LSOE and the modified LSOE with β=90° and ρ=0.36R respectively. A flat shape in VA curve was found in the rest of optical powers. CS shows a similar behavior, with a slight advantage of the angular window in respect of the radial one
the optimized LSOEs provide a better performance for distance vision than the original design, preserving a good behavior in near and intermediate vision, what validates suitable features of the modified LSOE for presbyopia correction
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.
This PDF is available to Subscribers Only