Effect of Double Refraction Within the Pupil Area on Visual Performance

M. Millodot; V.A. Brown

doi:10.65636/cjo.v46i4.7224

Authors

M. Millodot
V.A. Brown

DOI:

https://doi.org/10.65636/cjo.v46i4.7224

Keywords:

double refraction, visual performance, visual acuity, contrast sensitivity

Abstract

Standard visual acuity and contrast sensitivity were measured in subjects wearing their spectacle correction and the same but with a 2mm hole in the centre of the lens. It was found that visual acuity only diminished from 6/5.7 to 6/6.9 on average and that the contrast sensitivity differences were small and not systematic. This experiment supports the feasibility of simultaneous type of bifocal contact lenses.

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