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Monocular through-focus visual acuity (VA) for the 1.6 mm pupil (green squares), the 4 mm pupil (red squares), and the 5 mm pupil with obscuring annulus (green diamonds). When compared to performance with the 1.6 mm pupil, the 5 mm pupil with obscuring annulus decreases distance VA but increases performance at vergences greater than 1 D.
