1, the patient needs to take off his glasses:
2. At least 18 weeks old;
3. The diopter is stable in recent two years, and the development speed does not exceed 0.50 d per year;
4. Correction diopter range (myopia 150- 1500 degrees; Hyperopia 100-600 degrees; Astigmatism does not exceed 600 degrees);
5. anisometropia with different diopters in both eyes;
6. Those who wear contact lenses (soft lenses should be stopped for 1-2 weeks, and hard lenses should be stopped for 2-3 weeks. Pay attention to the shape and thickness of the visual angle film and the recovery of corneal epithelium);
7. Corneal thickness is greater than 450μ m;