Myopia is a very common eye disease, and we are all surrounded by friends who are more or less nearsighted, even ourselves. Although myopia is common, there has never been a particularly clear answer as to why it develops, and this is because there are so many causes of myopia. The development of most moderate and low myopia is related to excessive near vision during eye development. Myopia develops at a high rate between the ages of 12 and 18, which is a period of intense desire for knowledge and heavy study pressure for adolescents, who are busy with books and homework, and who spend a lot of time watching TV, playing computers, and playing video games, which significantly reduces outdoor activities, and who are nearsighted for a long time. When the anterior and posterior diameter of the eye becomes longer, the focus of the eye cannot fall on the retina accurately, which is the essential cause of myopia. Do not pay attention to the lighting and time when reading, not enough light, not enough brightness of lighting or reading and writing for several hours without rest, over time, the eyes will slowly become longer in front and rear diameter in order to adapt to this situation of looking close, forming myopia. In a sense, this is also an “evolution” of the eye itself, in order to better suit the evolution of prolonged viewing. In addition, when the curvature of the cornea or lens changes, the curvature of the cornea or the curvature of the lens in front of and behind the lens becomes larger, it also leads to a pathological increase in refractive power, causing the image to focus on the front of the retina and creating myopia.