Small-Pupil Performance Of Phase Ring-Based Intraocular Lens Designs

To evaluate the efficacy of PhaseRing™ across different pupil diameters, with particular emphasis on its performance under small pupil conditions.

University of Valencia

Through-focus modulation transfer function (MTF) measurements were performed on an optical bench using a model eye. Two IOLs incorporating the same PhaseRing™ concept but optimized for different functional profiles were evaluated: Asqelio™ Pluris™ (Partial-DOFi Enhanced design), and Asqelio™ EDOF (Partial-DOFi Extended design). The optical design combines an annular Phase Ring generating an extended focal region with a centrally optimized phase profile intended to preserve distance image quality.

MTF was measured at 50 lp/mm for entrance pupil diameters of 1.16, 2.32, and 3.48 mm, spanning photopic to mesopic conditions. Optical performance through focus was quantified as the continuous dioptric range over which MTF remained ≥ 0.1.

At the smallest entrance pupil (1.16 mm), both IOLs demonstrated high peak MTF values at distance (0.45-0.51 at 50 lp/mm) together with a broad through-focus response. A wide dioptric range with MTF ≥0.1 (4.5-4.8 D) was observed, indicating effective engagement of the Phase Ring under very small-pupil size.

At an entrance pupil of 2.32 mm and 3.48 mm, optical efficacy was preserved in both models maintaining the extended through-focus response. The Partial-DOFi Extended implementation exhibited a 0.5-1.0 D greater depth of focus compared with the Partial-DOFi Enhanced implementation.

Across the pupil diameters evaluated, the Phase Ring IOL concept maintains effective optical performance. Differences in depth of focus between Enhanced and Extended implementations become more evident at larger pupils, while efficacy is preserved even at very small entrance pupil diameters.