The National Health Planning Commission requires all relevant departments to vigorously popularize scientific eye knowledge, cultivate good eye habits among students and prevent refractive errors. Children between the ages of 3 and 5 are generally able to achieve a visual acuity of 1.0. By the age of 4, a standard vision chart can be used to check a child’s vision. Hang the chart in a well-lit area, have the child stand at a prescribed distance, cover one eye with an eye shield, and perform a monocular examination. Visual acuity in both eyes is considered normal if they each have a visual acuity of 1.0. Generally, young children between the ages of 2 and 3 years old are able to see half as well as adults. Most parents do not observe their children’s vision carefully enough, thinking that if the child responds to the items sent to them, it means that there is no problem with vision. In fact, due to parental negligence, some children’s congenital and hereditary eye diseases are not detected early and miss the best deadline for treatment, and some affected children may not even recover for the rest of their lives, which is a pity. How to detect vision abnormalities in children as early as possible? For infants and toddlers, it is difficult to perform vision screening because we cannot test their vision using a standard vision chart. However, if parents are careful, they can catch problems from their child’s usual behavior. For example, when noticing that the child is always squinting or looking at an object with both eyes not in the same parallel position, asking the child to watch some small animal patterns (some places have image vision charts), or covering one of the child’s eyes with a hand to observe whether the child can continue to play normally, etc. If the child refuses the parent’s shield, consider whether the uncovered eye has poor vision. Newborn infants have a very low level of vision, and their vision gradually improves only 1-2 weeks after birth, preferring soft scattered light and hating strong direct light; around 2 months of age, infants can turn their eyes with their mother’s facial activity when drinking milk (some infants earlier); at 4 months of age, their vision is equivalent to 0.02 At 4 months of age, vision is 0.02 -0.05, and the infant can show excitement at the sight of brightly colored objects (medically known as the “optokinetic response”, which refers to the binocular response of a normal nursing infant to visual stimuli that appear in front of him/her). If your child is at this age and does not respond as described above, parents should think that there may be a vision problem. At 8 months of age, both eyes are able to fixate on an object; at about 1 year of age, toddlers are interested in more distant and smaller things, such as looking through a window at a child playing downstairs or a television screen that is not in front of them. At this time, colored objects can be used to check the eyesight of infants and toddlers. Parents should tease their toddlers with colorful toys and carefully observe their eyes’ reaction when teasing them, whether they can track the movement of the toys and whether they can accurately capture the target. After checking both eyes, it is best to check the child’s unilateral eye separately. Once you find something wrong with your child’s eyes, you should go to the hospital for further detailed examination in order to determine the real cause of the eye disease. In short, the earlier it is detected, the better the treatment will be.