Q: What does refractive error mean? A: Refractive error means that when the eye is relaxed, parallel light rays are not clearly focused on the retina and external objects cannot be seen. It includes nearsightedness, farsightedness and astigmatism. Q: What is myopia? A: It is a refractive state in which parallel light rays are refracted through the refractive system when the eye is not adjusted and the focus falls in front of the retina. It is characterized by the inability to see distant objects, but can clearly see objects at close range. Q: What is hyperopia? A: Because the focal point falls behind the retina, a diffuse circle is formed on the retina, so it is impossible for external objects to form a clear image on the retina and affect vision. Therefore, farsightedness requires the eye to use its regulating function whether it sees near or far, otherwise it will not be able to see all objects. Q: What is astigmatism? A: Astigmatism is a refractive state in which the eye has different refractive power in different lines of vision. In other words, astigmatism is a condition in which the light coming into the eye from outside cannot be collected into a focal point, and therefore no clear image can be formed on the retina. Q: When do I need glasses? Myopia is divided into true myopia and pseudomyopia, and according to statistics, about 95% or more are true myopia. If myopia is pseudomyopia, vision can be improved by using ciliary paralytic eye liquids, taking rest and correcting eye habits; if myopia is true, a pair of glasses is needed. This bad habit will further aggravate his myopia. Q: What are the effective means of myopia prevention? 1, pay attention to eye health: pay attention to reasonable eye use, develop a good sitting posture, pay attention to keep the distance when doing homework, do not read and write for a long time at close range, watch TV, Internet, etc., every 40 minutes of work rest (far-sighted) 10 minutes to prevent excessive fatigue of the eye muscle; do homework when the light can not be too strong or too weak, try to reduce abnormal visual stimulation. 2, adhere to do eye exercises 3, reasonable diet: not partial diet, balanced nutritional intake, and eat less candy and high-sugar foods. 4.Regular checkups: Go to the hospital for vision and refractive examinations, and deal with any problems promptly. Q: Do a large number of instruments to prevent myopia and promote visual rehabilitation work? Don’t believe in those instruments for myopia treatment in newspapers, on TV. The root of treating myopia is to have good living habits, eye habits and some ways to protect your eyes. Treating myopia is not a matter of 1~2 days.