TORIC INTRAOCULAR LENS WITH SPATIALLY-VARIANT ASTIGMATISM

摘要

An intraocular lens for correcting or reducing the astigmatism of a corneaincludes a pupil that is spatially dividedinto discrete zones, with each zone having a particular astigmatism magnitudeand astigmatism orientation. In one embodiment,the zones all have the same astigmatism magnitude, which is equal and oppositethe cornea astigmatism magnitude to within apar-ticular tolerance, such as 0.25 diopters. In one embodiment, some or allof the zones all have different astigmatism orientations,with the angular separation between astigmatism orientations being on theorder of the rotational misalignment tolerance of thelens to the cornea. The visual performance of such a lens deteriorates moreslowly with rotational misalignment, when comparedto a comparable lens having a uniform astigmatism orientation across itsentire pupil, leading to more relaxed tolerances for asur-geon that implants the lens.