Reading glasses are used to supplement the vision of middle-aged and elderly people. Like myopia glasses, there are many optical indicators stipulated by national standards, and there are also some special rules of use. The use of reading glasses plays an indispensable role in improving people's quality of life.
Presbyopia is a normal physiological phenomenon, not an eye disease, and it is not unique to the elderly. After the age of 40, with the gradual sclerosis of the lens of the human eye and the gradual paralysis of the ciliary muscle, the human eye cannot effectively adjust the shape of the eyeball (axial change). When an object must be moved away to see clearly, the eye condition at this time is called presbyopia.
If presbyopia wants to use vision at the original accustomed distance, it is necessary to wear reading glasses to supplement the vision, so that the near vision can be clear again. It is no exaggeration to say that reading glasses are the second pair of eyes for everyone after entering middle age. Presbyopia is related to age. For example, presbyopia at age 45 is +1.50D (ie 150 degrees), and at age 50, presbyopia increases to +2.00D (ie 200 degrees) whether you wear glasses or not. Presbyopia has already appeared, and if you insist on not wearing reading glasses, your ciliary muscles will be exhausted and you will not be able to adjust. Therefore, the reading glasses are ready to match, do not delay. After the age increases, the original reading glasses are not enough, and they should be replaced in time. Therefore, reading glasses cannot be worn to the end. Wearing inappropriate reading glasses for a long time will not only bring a lot of inconvenience to your life, but also accelerate the process of presbyopia.
Under normal circumstances, there are two main manifestations of presbyopia in the early stage: the first is difficulty in working at close range or reading. For example, when reading, you need to hold the book far away, or you need to read in a place with strong light to see clearly. The second is visual fatigue. With the decline of accommodation power, the reading demand gradually approaches the limit of accommodation power, that is, when reading, almost all the accommodation power of the eyes must be used, which leads to the inability to use the eyes for a long time. symptom. The above two phenomena appear, it means that the eyes may start to get old. For people with myopia, it is necessary to take off the glasses or pull the reading material away when reading at close range, which is also a manifestation of presbyopia. After presbyopia, the safest way is to wear appropriate reading glasses for correction
