Abstract

Interferometric methods are valuable for two main reasons in the determination of actual or potential visual acuity in patients with a variety of pathologies. First, light enters the eye as two closely spaced bundles of rays which can be maneuvered to avoid opacities of the ocular media. Second, the test pattern consists of interference fringes formed directly on the retina without being focused by the eye's natural optical system. Consequently, the image quality produced by such an instrument is largely unaffected by ocular errors of focus, such as astigmatism, coma, spherical aberration and longitudinal chromatic aberration (Westheimer, 1960).

© 1987 Optical Society of America