Patent ID: 7287855

Claim:
A machine-implemented method for analyzing the birefringence (δ N , θ N ) of the retinal structure of an eye having a pupil and an anterior segment that includes all regions anterior to the retinal structure, the method comprising the unordered steps of: (a) producing an optical diagnostic signal having a predetermined polarization state [S 1 ]; (b) disposing a bias retarder such that the joint birefringence (δ J , θ J ) of the bias retarder and anterior segment combination has a nonzero retardance magnitude δ J ; (c) directing the optical diagnostic signal along a path through the bias retarder, into the pupil and the anterior segment such that the optical diagnostic signal impinges on a selectable region of the retinal structure and reflects therefrom to establish a reflected optical diagnostic signal having a polarization state [S 2 ] representing a total birefringence (δ T , θ T ) along the path; (d) determining a retartdance magnitude δ N and orientation angle θ N of the retinal structure birefringence (δ N , θ N ) by removing the effects of the joint birfringence (δ J , θ J ) from the total birefringence (δ T , θ T ), said determining step being achieved without having to establish a separate reflected optical diagnostic signal wherein the bias retarder is disposed in a manner to cancel the birefringence of the anterior segment; and (e) storing or displaying at least one of the determined retardance magnitude δ N and orientation angle θ N .