Method and apparatus for improved fundus imaging through choice of light polarisation

Abstract

The present invention provides a method and device to image the fundus of the eye using polarized light which includes circular polarization. The invention is most broadly comprised of a device to generate polarization states of light, including circularly polarized light (i.e. potentially combinations of elliptically polarized light and depolarized light combined, elliptically polarized light alone, or circularly polarized light with depolarized light or circularly polarized light alone). This light can be used with any fundus imaging device including but not limited to fundus cameras, scanning laser ophthalmoscopes, confocal scanning laser ophthalmoscopes, optical coherence tomography instruments, with or without some form of wavefront correction. This is a change from common fundus imaging systems which use randomly polarized light or linearly polarized light. The simplest implementation of this is a quarter wave plate (or equivalent retarder) combined with a linear polarizer located after the light source and before the eye. The QWP can be rotated to produce differing circular and elliptical polarizations of light which are ideal for imaging differing structures at the rear of the eye for different people.

Dependencies are inferred from the claim text.