Many people think that optometry is simple, but in fact, optometry is not a commercial practice, but a medical practice that needs to be carried out under the guidance of an ophthalmologist. It is a medical practice that needs to be done under the guidance of an ophthalmologist. The glasses that are fitted will be clear, comfortable and long-lasting. Medical optometry is a method that takes both eyes as a whole, fully considers the patient’s age, eye habits, dominant eye, eye position, adjustment power and many other factors, and gives the best choice of prescription by professional optometrist through ophthalmology equipment to examine the patient. It is the most scientific method of optometry, while ordinary conventional optometry refers to the optometry in general optical stores, the operation method and steps are relatively simple, only through the inserts or computerized optometry for optometry and prescription glasses, its purpose is only to let refractive error people see clearly objects. The standardized and complete medical optometry process includes basic ophthalmic examination, subjective optometry, objective comprehensive optometry, eye disease investigation and other steps; compared with ordinary optometry, medical optometry has the characteristics of accuracy, science, safety and reliability, which can protect the visual health of human eyes to the greatest extent. Medical optometry has the following advantages: 1, control the development of myopia: accurate refractive examination and prescription can allow myopic patients to see external objects clearly, eliminate the factors that cause myopia, and control the development of myopia. 2, correction of complex refractive errors: for eyes with eye diseases, eyes that have undergone eye surgery refractive abnormalities and some complex refractive conditions, medical optometry can meet the refractive correction of such abnormal complexities. 3, early detection of children’s refractive abnormalities and timely treatment: children’s strabismus, amblyopia: children’s refractive error not only affects children’s vision, but also can lead to strabismus and amblyopia. Many children with strabismus and amblyopia are accompanied by refractive abnormalities. Ordinary optometry can not solve these problems, only through medical optometry and fitting to treat. 4, medical optometry is also an important means of examination for disease diagnosis. Through medical optometry, the ophthalmologist can understand the impact of the patient’s refractive state on the patient’s vision, clarify the nature and extent of the patient’s eye disease, and provide an important reference basis for the diagnosis and treatment of the disease. 5, qualified glasses need medical optometry to ensure. The key to qualified eyeglasses is the standardization and accuracy of optometry, and the general principle is that students before school age should undergo atropine dilated pupil medical optometry; 8-14 years old students without internal strabismus, hyperopia less than 3.00 degrees can undergo rapid dilated pupil optometry; age less than 8 years old, hyperopia greater than 3.00 degrees, children with internal strabismus should undergo atropine dilated pupil. 18 years old After the age of 18, optometry can be performed without pupil dilatation, and trial lenses can be performed directly after optometry. For adolescents with strong adjustment ability, pupil dilatation is needed to eliminate the effect of adjustment on the optometry, so that the optometry can be more accurate, and retesting and trial lenses are based on the original photometry and reasonable adjustment according to the patient’s feelings.