Usually, when a person is about 45 years old, he or she develops blurred vision when reading or working at close range, and there is a tendency for the vision in both eyes to get worse every year, which is called presbyopia, commonly known as presbyopia. Presbyopia is a normal physiological phenomenon. This is because the regulation of the eyes is strongest around the age of 10, but as we grow older, this regulation will gradually weaken, and around the age of 45 the remaining regulation is weaker, and the distance to the near-sighted point gradually increases, and gradually can not see the near object clearly, then the phenomenon of presbyopia appears. Presbyopic glasses are a kind of convex lens, and patients can only achieve the purpose of supplementing the adjustment power of the eyes and treating presbyopia by wearing suitable presbyopic glasses. The first thing you need to do is to have an accurate optometry. The accuracy of the optometry is directly related to the patient’s vision adjustment. Some opticians in the market nowadays advocate computerized scientific optometry, which is actually a misleading to consumers. Only by going to a professional hospital and having a professional technician conduct a scientific manual optometry to determine the degree and pupil spacing data, can you get glasses that suit you. Before optometry, we must first determine whether there is myopia, hyperopia and astigmatism, and then increase or decrease the refraction according to age and the degree of presbyopia. In general, the degree of presbyopia is proportional to the age. 40 years old, about 50 degrees of presbyopia; 50 years old, about 200 degrees; 55 years old, about 300 degrees; 60 years old and above, about 350 degrees to 400 degrees. If you have myopia, farsightedness and astigmatism, you should add or subtract degrees when you get glasses. Patients with myopia should subtract the normal age of presbyopia from the myopia. For example, the original 200 degrees of myopia, now age 45 (the normal age of presbyopia for 100 degrees), in fact, only wear 100 degrees of myopic lenses can see the near objects. If you have farsightedness, you should add the degree of farsightedness to the normal age of presbyopia. For example, if you are also 45 years old and have 200 degrees of farsightedness, you should actually wear 300 degrees of presbyopia. Of course, with presbyopic glasses, you should also combine the distance you are used to seeing things, and increase or decrease the number of lenses appropriately.