INTRAOCULAR LENS Russian patent published in 2008 - IPC A61F2/16 

FIELD: medicine.

SUBSTANCE: eye lens contains optic element having front and back surfaces. Optic element ensures optic force in the range of 16 to 25 dioptres. Thereat at least one of the above said surfaces is characterized by such aspheric basic profile that optic element ensures negative spherical aberration in the range from -0.202 μ to -0.190 μ along the entire above mentioned range of the optic force. Optic element may contain principle plane ensuring alteration of displacement in the range from -0.019 mm to +0.018 mm from the selected plane of the above mentioned optic element. In one of the versions of the eye lens, profile of at least one of the above said surfaces is characterised by the following ratio: , where z stands for surface deflection on radial distance r from the optic axis of the lens, c is surface curvature in its cross point with the optic axis, k stands for conical constant, a₁ is a coefficient of second - order asphericity, a₂ is a coefficient of fourth-order asphericity, a₃ is a coefficient of sixth-order asphericity , whereat c changes from -0.0369 (1/27.1) mm^-1 to 0.0541 (1/18.5) mm^-1, k changes from -73 to -27, a₁ changes from -0.000209 mm^-1 to -0.000264 mm^-1, a₂ changes from -0.0000297 mm^-3 to -0.0000131 mm^-3, and a₃ changes from 0.00000978 mm^-5 to 0.00000846 mm_,.

EFFECT: ensures correction of spherical aberration.

18 cl, 4 dwg, 2 tbl, 1 ex