If you want to know whether you have myopia or not, or how much myopia you have, you must go to a regular hospital to have an optometry examination, which is the gold standard for myopia checking, and can also accurately determine whether your eyes have myopia or not. There are two types of optometry, the first one is subjective optometry and the second one is objective optometry. At present, the main application is objective optometry, which includes both photoplethysmography and computerized optometry. For children or adolescents under the age of 14, it is generally recommended that the optometry examination be conducted under dilated pupils, only in this way can the eye’s own adjusting function be removed, thus truly reflecting the refractive state of the eyes. Subjective optometry, also known as insertion of lenses, is mainly used for patients who cannot cooperate with computerized optometry, and the results of this type of optometry have certain limitations.