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There is a problem in photorefractive eye microsurgery of mapping the refraction distribution in the eye, caused by distortions of the cornea shape, lens aberrations, and non- homogeneities of the components of eye media. We investigated shearing interferometer and Shack-Hartmann sensor for obtaining the refraction map without procedure of scanning. Like in adaptive optics, Shack-Hartmann sensor uses a microlens matrix that transforms wave front of a retinal single point source into plurality of sections giving point projections ont eh photodetector matrix. Displacement of these points from zero positions determines local wave front distortions, corresponding to refraction distribution. Shearing interferometry needs two sets of 2D data go at two orthogonal beam offsets. Shack-Hartmann sensor gets the entire information at one single measurement. Multiplexed aberrationless hologram is used for avoiding the errors caused by microlenses positioning. Sensitivity better than 0.1 diopter of refraction non- homogeneity measurement can be reached and is limited by several factors, signal-to-noise ratio being the principal.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only. |
