Fig. 3

Double-angle plots for astigmatism were measured by the (a) Eyestar 900 swept-source optical coherence tomography (SS-OCT) and (b) the Lenstar LS 900 Optical Low Coherence Reflectometry (OLCR) biometers. These graphs show centroid and mean absolute values, the standard deviation and 95% confidence ellipses of the centroid and the dataset (each ring = 1.00 D)