Amblyopia is a common eye disease during childhood development and can be cured by correcting refractive errors and performing amblyopia training. Because of the long period of amblyopia treatment, parents are particularly confused and have many questions. What is the concept of amblyopia, hyperopia, myopia, astigmatism and strabismus. Why must a child diagnosed with refractive amblyopia wear glasses to correct it and then treat the amblyopia. What is the general cause and effect relationship between these types of refractive errors and strabismic amblyopia. Without understanding these issues, it is impossible to recognize the importance of treating amblyopia. Let’s explain them one by one. Children with amblyopia do not only have lower than normal visual acuity, but even after wearing glasses to correct refractive errors, their visual acuity still does not reach normal levels, and they often do not have perfect stereopsis. The amblyopic eye has no organic lesions and no abnormalities in the ocular morphology or structure on examination, because it is difficult for younger children to accurately express their visual acuity level and is not easily detected in time. Human vision is not innately acquired, infants are born with a response to light, but the eyes are not fully developed, the visual structure and optic nerve are not yet mature, the visual field is only about 45 degrees, and the visual acuity is only 1/30 of an adult’s. They can only follow people or objects in the horizontal direction and 18 to 38 centimeters in front of them. As we grow older, the visual cells in both eyes continue to develop and improve. 5 years of age is an important period for the development of visual function, and visual development continues until 6-8 years of age, if for some reason this period causes visual impairment, the visual cells do not receive normal stimulation, and visual function remains at a low level to form amblyopia. Amblyopia can occur during visual development, mostly starting at the age of 1 to 2 years. The earlier the onset of amblyopia, the more severe it becomes. The presence of hyperopia, myopia, astigmatism and strabismus in young children may affect the ability of the eye to receive adequate visual stimulation during development, thus causing amblyopia. Farsightedness is a refractive error in which parallel light rays enter the eye and form a focal point behind the retina and external objects do not form a clear image on the retina. When newborns are born, their eyes are smaller than those of adults, and the distance between their eye axes is much shorter than that of a mature eye, so the image is formed behind the retina and is therefore farsighted. This is a normal process of eye development and is called physiological hyperopia. As the anterior and posterior diameters of the eye grow and lengthen accordingly, the visual acuity gradually normalizes with age and is called orthophoria. So if your child’s hyperopia is within the range of physiological hyperopia after optometry, there is no need to be alarmed. On the contrary, if the child is not farsighted or only mildly farsighted by the age of 3 or 4, it means that the process of orthophoria is too fast and myopia will be formed if the child continues to develop. Parents should pay attention to their children’s eye hygiene to control the development of myopia. What can cause amblyopia is high hyperopia, which needs to be corrected in time. Myopia is a refractive error in which parallel light rays enter the eye and form a focal point before the retina and external objects do not form a clear image on the retina. Because myopia does not affect near vision although it cannot see far away, and because infants are less likely to suffer from simple myopia, amblyopia caused by myopia is generally rare. However, pathologically high myopia can occur in infants and young children, severely damaging vision and should be corrected promptly. Astigmatism is caused by the inconsistent refractive index of the corneal meridians, which prevents light rays passing through these meridians from converging on the same focal point. The object cannot form a clear image on the retina, and this refractive error is called astigmatism. Astigmatism of large magnitude is one of the causes of amblyopia and should be corrected promptly if detected. Strabismus is often mentioned in medical practice, so the two are closely related. In children with strabismus, when one eye looks directly at the target, the other eye is tilted to the side. Some children will fix one eye to look at something, and the other eye will always be skewed to one side. Over time, the eye that is repeatedly stimulated develops visually, while the other eye that cannot look is delayed in its development, forming monocular amblyopia. Parents need to remember that the discovery of amblyopia must be treated in a timely manner, if you miss the critical period of vision development in children, amblyopia can not be cured.