Excimer laser and femtosecond laser are commonly used to correct myopia, and the requirements for laser surgery are as follows: 1. Age above 18, myopia stabilized for more than two years, and a desire to remove glasses on their own initiative.2. No keloid, connective tissue disease, or severe dry eye, etc. 3. No acute or chronic inflammation in the eye, corneal thickness sufficiently thick, pupil with no obvious abnormality, funduscopic examination reveals no obvious retinal detachment, lacrimation or severe degeneration area, corneal topography examination did not find obvious abnormality, intraocular pressure measurement within the normal range.4. Lacrimal flushing to exclude the possibility of chronic dacryocystitis.