1, age 18-50 years old; 2, myopia 100-2000 degrees; 3, no other eye diseases such as cone cornea, too thin cornea, cataract, glaucoma and other active eye diseases. 4, no systemic diseases, such as scar body and immune diseases patients are not suitable for surgery, such people are prone to corneal haze and refractive regression. In addition, there are hypertension, diabetes, malignant tumor patients are also not suitable for surgery. 5.No mental disorder. 6, have a strong desire to remove the lens.