Patent ID: 7494220
Filing Date: 2009-02-24
Classification: A61B

Abstract:
1. A method for improving the calculation of sphere and cylinder in an autorefraction by determining a distance between photoreceptors and a scattering location in a subject's eye, comprising: performing an autorefraction of the eye with an objective refractor to calculate a sphere and cylinder value for the eye; focusing the eye on a rotating speckled light pattern; adjusting a distance between the speckled light pattern and the eye until the speckled light pattern appears to be stationary; measuring the distance between the speckled light pattern and the eye when the speckled light pattern appears to the subject to be stationary; calculating the distance between the photoreceptors and the scattering location based on the distance between the speckled light pattern and the eye; and adjusting the sphere and cylinder calculation to include the calculated distance between the photoreceptors and the scattering location.