| 摘要 |
FIELD: medicine.SUBSTANCE: eye cornea is exposed to an eximer laser light at wave length 193-222 nm, pulse energy 0.8-2.1 mJ, laser spot diameter 0.5-1.5 mm, pulse length 5-8 nm, pulse repetition frequency 30 to 500 Hz. This expose aiming at a sequential corneal abrasion is combined with forming optical surfaces and transition surfaces. A first spherical convex optical surface is formed within the entire optical cornea (OC), including the OC centre. A second optical surface is formed as a convex ellipsoid of rotation with a positive conic constant within +0.75 to +1.5. An optical axis of the second optical surface matches with the OC centre. A diameter of the second optical surface is related to an OC diameter as a value within the range of 0.85 to 0.95. Then, the transitions surfaces (TS) are formed. The first TS is formed as a portion of a convex outer surface of a first O-toroid. The second TS is formed as a portion of a concave inner surface of a second O-toroid. The second TS is formed so that its inner border is coupled with an outer border of the first optical surface. The outer border of the second TS shall be coupled with the inner border of the first TS.EFFECT: method enables minimising the amount of the resected eye tissue, provides the high far and near visual functions with no additional spectacle correction with decreased light cap.22 dwg, 3 ex |
