Excimer laser treatment of refractive error can be achieved by changing the surface curvature of the cornea. Excimer laser treatment of refractive error utilizes this principle and the unique advantages of excimer laser: 1, it relies on the photochemical effect to directly break the chemical bond of the tissue to do tissue cutting, and the cutting is very precise. 2. It is a cold laser, which basically has no thermal effect on the surrounding tissues. The laser can be used to cut the cornea and reshape the corneal surface to correct myopia, hyperopia, astigmatism and other refractive errors of different nature. The amount of laser cutting and the cutting method vary depending on the nature of the refractive error of the patient, usually the amount of laser cutting is larger for high refractive error with the same cutting area, and smaller vice versa. For the treatment of myopia, the excimer laser cuts more tissue in the central part of the cornea than in the peripheral part of the cornea, making the central curvature of the cornea smaller, similar to grinding a “concave” lens on the cornea to correct myopia; conversely, for the treatment of hyperopia, the excimer laser mainly cuts the peripheral part of the cornea, while retaining the central part of the cornea to increase the relative size of the cornea. In contrast, in the case of hyperopia, the excimer laser mainly cuts the peripheral part of the cornea, while leaving the central part of the cornea intact, in order to relatively increase the central curvature of the cornea, similar to grinding a “convex” lens on the cornea. It is also possible to use wavefront aberration guidance, corneal topography guidance, or wavefront optimization guidance to individualize the tissue cut using flypoint scanning, resulting in a reshaped cornea that is more conducive to reducing ocular aberrations and further improving postoperative visual quality.