The development of the refractive state of the child’s eye has a certain pattern, and its normal refractive state develops along the direction of change from hyperopia to orthopia. If there is a problem with the eye environment at this stage, the development from ortho-opia to myopia will occur, and the total development trend is irreversible. When a person is born, the normal anterior and posterior diameter of the eye is short, only 16-17.1mm, and the baby has +2.00D to +4.00D of hyperopia. In the 1 to 3 years after birth, the eye is in a period of rapid development, the eye axis grows rapidly, and the eye axis is generally about 16-19.5mm long; from 3 to 18 years old, the eye is in a period of slow development, and the length of the eye axis is about 19.5-23mm. Therefore, a 3-year-old child should be +1.75D-+2.00D hyperopic; an 8-year-old child should have +1.25-+1.50D hyperopia; a 12-year-old child should have +0.75-+1.00D hyperopia. Therefore, it is normal for children under 6 years of age to have mild hyperopia and to have visual acuity of 1.0 or less though (but should be above 0.6). With preschool hyperopia, a slow decrease in hyperopic refractive error after entering elementary school, and a somewhat hyperopic reserve at age 12 is the optimal refractive state, and the probability of producing school myopia will be low. According to the calculation of the geometric optics of the eye, every 1mm growth of the eye axis will produce 3.00D myopia; and there is another very important refractive element in the development of children’s eyes – that is the corneal curvature of the front surface of the eye. Every 1mm increase in the radius of corneal curvature offsets 6.00D myopia. In the 3 years after birth, the human eye develops as the eye axis grows while the radius of corneal curvature grows in a matching manner, basically remaining hyperopic. From the age of 3 to 10, the eye develops toward orthokerativity, and by the age of 10, the eye is close to adult development, with an average eye axis length of about 23.5 mm. During the development of the adolescent eye, the development of the refractive state of the eye is closely related to the visual environment, especially the two values of the eye axis (length of the anterior and posterior diameter of the eye) and curvature (curvature of the surface of the eye) are the most sensitive. The developmental match between these two values of the eye during a child’s growth period determines whether the eye is ortho-, hyper-, myopic or astigmatic. Studies have found that excessive near eye use and lack of outdoor exercise during the developmental period of the eye are the main causes of an eye axis that is longer than normal, making both axis and curvature values more important and objective in the prediction and diagnosis of myopia, as well as the measurement of corneal curvature, which is important in the classification and diagnosis of astigmatism. Since the development of myopia is irreversible, scientific testing based on the developmental pattern of the eye can identify potential hidden myopia patients early, which is extremely important for the prevention and control of myopia. How to delay the onset of myopia? How to control the rapid development of myopia? Through timely biometry and prediction of the eye, practical interventions can be targeted to prevent myopia before it happens. Therefore, we advocate that children should undergo eye examinations at the age of 3, establish a refractive eye development file, and have their refractive status examined and monitored regularly, so that they do not have to go to the hospital only when their vision has irreversibly decreased.