Prolonged and continuous use of the eyes to look at the near is prone to excessive strain on the regulatory function, increased pressure in the eye and pressure on the extraocular muscles, which may be the cause of myopia. Overstrain of the regulating function should be the main cause. As a result of continuous near vision, the regulatory function must be constantly under tension and without proper rest, and fatigue must occur after a long period of time. In the case of excessive fatigue of the regulatory function, the eyes will become very difficult to see close. The growing eye, in order to reduce the burden on the regulatory function, but also to adapt to the need to see close, only to promote the front and back axis of the eye becomes longer, the formation of myopia. When the eye is used for near vision, the contraction of the ciliary muscle and the protrusion of the lens in front of the eye will cause the pressure in the eye to rise. The long-term increase in intraocular pressure compresses the wall of the eye, causing the sclera to dilate and the anterior-posterior axis of the eye to elongate, resulting in the refractive state of myopia. When the eyes look close, the two eyes have to gather toward the center and jointly focus on the near target. In such a situation, the muscles on the outside of the left and right eyes, press tightly against the outside of the eye. The closer the distance when looking closer, the tighter the compression. The tense pressure of the extraocular muscles can contribute to the elongation of the anterior-posterior axis of the eye, creating the refractive state of myopic eyes.