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. 2022 Feb 25;16:489–505. doi: 10.2147/OPTH.S342666

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© 2022 Arnold et al.

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Ellipsoid comparison of refractive component from three infrared autorefractive devices compared to refined retinoscopy. Left shows ellipsoid composite metric (0 = perfect spectacle match, 1.0 is 1 line blue, 2.0 is 3 line defocus nd 3.0 corresponds to a 6 line defocus).