Methods and systems for correction of hyperopia and/or astigmatism using ablative radiation

摘要

Methods and apparatus for corneal reprofiling are disclosed in which a beam-swapping assembly is employed to redirect rays of ablative radiation passing through the assembly. Essentially, the beam-swapping assembly turns the beam profile "inside out" redirecting the inner most rays to the periphery of the beam while redirecting the outer rays at the same time to the center of the beam. The beam-swapping assembly can be used in conjunction with a beam-shaper, such as an adjustable iris or other beam- shaping device, to create convoluted annular ablation patterns of variable depth and, thereby, perform hyperopia and/or astigmatism correcting procedures.