Fig. 14. Variable corneal compensator. The top image shows an alteration in the normal retardation pattern of the macula as a result of uncompensated corneal birefringence. A supranormal retardation pattern is seen at the superior and inferior poles of the optic disc. The bottom image, with appropriate corneal compensation, depicts the normal macular retardation pattern caused by the radially arranged Henle fibers. A normal retardation pattern is seen at the optic disc.