V. V. Molebny, I. H. Chyzh, V. M. Sokurenko, S. V. Molebny, I. G. Pallikaris, L. P. Naoumidis.
Phase-transparency model of an eye optical system // SPIE Proceeding. - 1997. - Vol. 3192. - P. 233-242.
In photorefractive sight correction, pre-operational computations of to-be-ablated layers are usually based on
information about cornea shape that is one of the causes of aberrations. To obtain high-quality results of operation,
contributions to aberrations of other origins are to be taken into account. Technique of eye-aberration mapping has been
investigated, we called retina ray-tracing. It consists in directing into the eye a narrow beam, scanned (translated) in parallel
to itself. Computer controls trajectory of scanning. Beam projection (spot of light) is formed on the retina. Aberrations result
in varying position of the spot on retina in the course of scanning. Deviations from initial position are measured and
reconstructed into wave aberration function. Mathematical relations, using Zernike polynomial expansions, were found to
transform these data into necessary cornea shape correction with ablation technologies. In our experimental setup, we used
the technique of acousto-optic scanning with frame time less than 10 ms for 65 sensed points. Eye-aberration mapping is
realized with optical power resolution 0.1 diopter.
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