With the popularization of electronic products, many middle-aged people around the age of 45 begin to develop presbyopia early, and some even develop presbyopia at the age of 40. The main manifestation is that after middle age, when looking at near objects, the eyes become sore, swollen, tearing and other phenomena that cannot last or strain, which suggests that our middle-aged and elderly friends need to wear presbyopia glasses. The main reason is that as we grow older, the elasticity of our lens becomes weaker and the regulation of ciliary muscle decreases, resulting in a decrease in the overall regulation of the eyes.
After the age of 45, people with low myopia can see very easily when they take their glasses off. This is not to say that a person with low myopia will not experience presbyopia, but rather that the amount of presbyopia just offsets the amount of myopia he has. Medium and high myopia people are more painful, wear glasses to see near objects can not see, take off the glasses can not see, he needs to wear a pair of myopia than the original number of degrees lower than about 100 degrees of myopia can see near. For example, the original look at the distance to wear myopia -5.00 degrees very clear, and now wear -4.00 degrees or so can look at the near. Orthokeratology (no myopia or hyperopia, eyes with normal vision) now only need to wear +1.00 degrees or so of prescription lenses to see near. People with farsighted eyes have to wear much higher prescription lenses than their peers (myopic or orthopic eyes).
When we develop presbyopia, a phenomenon occurs: we need to wear a pair of distance glasses (except for orthokeratology) to see and walk, and another pair of near glasses (presbyopia) to read and write, switching back and forth between the two pairs of glasses, which is particularly troublesome. When we need to wear presbyopes to see close, we are also sending a message to the people around us - I'm getting old. This is contrary to our ideal of pursuing a better life! So, is there a kind of glasses can be both near and far so that when we look at close objects, others do not know that we appear presbyopia? The answer is yes, that is progressive multifocal glasses!
Progressive multifocal lenses, by decreasing (myopia) or increasing (hyperopia) the number of diopters in the vision channel, realize the use of different diopters when looking at objects at far, medium and near distances, reducing or compensating for the use of adjusting power, so that the wearer does not have to pay too much for adjusting power, so that the wearer can achieve the desire of clearness in both far, medium and near distances.
Not everyone can wear progressive multifocal glasses, the difference between the two eyes is more than 2.00DS, motion sickness and seasickness, inner ear dysfunction, short neck, cervical spondylosis, heart disease, blood pressure and blood lipids are not normal, these symptoms are not allowed to wear or try not to wear progressive multifocal lenses. In this case, it is best to wear two pairs of glasses, one for distance and one for near, which is more comfortable and safe.
When fitting glasses, you should choose larger frames, and the height of the frames should be around 33mm, because the lenses should be divided into distance, medium and near zones from top to bottom, and only if the frames are high enough, can you ensure that there is a wide enough near zone. It usually takes about a week to get used to the lenses, but the length of the adaptation period varies from person to person, and you should walk slower when you are dizzy. Since there are blind spots on both sides of the lens, you need to turn your neck and eyeballs at the same time to see objects on both sides. When going down the stairs, wear your glasses little lower, and try to make both eyes look out from the upper far-use area. Also know the principle of first static after moving, that is, first in the living room to watch TV or look into the distance, after dinner can wear glasses to the outdoors for a walk, so repeated for a few days and then drive to use, which is safer.