What are the advantages and disadvantages of bifocal reading glasses?
The advantage of bifocal reading glasses is a large field of vision, and they can be used with the same pair of glasses to see far, near. The cost is lower. But different areas have obvious intervals, and the appearance is not beautiful. The middle distance is fuzzy. They need to adapt to the period. Bifocal reading glasses lens is divided into two parts, and the degree of the two parts is not the same. The upper part is the mother of the flat area to see far, and the next part is the child of the reading area to see near. There is an obvious interval. The appearance is not beautiful. There is no transition area between two different areas, so its vision is fuzzy, easy to produce a 'jump image'. Long-term wearing will make people dizzy or fall down when climbing stairs.
What is a progressive lens?
Progressive multifocal lenses are lenses with different upper and lower powers for seeing far above and below for seeing near. The distance from the fixed far power above the lens to the near power fixed below the lens does not change suddenly, but a gradual transition between the two through the gradual change in refractive power. Compared with ordinary lenses, there are many advantages. The appearance of the lens is like a single vision lens, and the dividing line of the power change is not visible. Not only is the appearance beautiful, but more importantly, it protects the age privacy of the wearer, and there is no need to worry about revealing the age secret due to wearing glasses.
Since the change of the lens power is gradual, there will be no image jump. It is comfortable to wear and easy to adapt. So it is easy to be accepted. Because the degree is gradual, the replacement of the adjustment effect is gradually increased according to the shortening of the short distance. There is no adjustment fluctuation, and it is not easy to cause visual fatigue. Clear vision can be obtained at all distances in the visual range.
Such a pair of glasses meets the use of long-distance, near-use and various distances in the middle at the same time. It is especially good news for teachers, doctors, music workers, and computer operators, because these people not only need to see far and near objects clearly, but most of the time they also need to be able to see middle distance objects such as blackboards, piano scores, and computer screens. . This is not possible with any lens other than progressive lenses.
Understand the basic knowledge of prescription of glasses
The prescription mainly includes the refractive status of the eye, degree of correction required, pupil distance, and the purpose of using the lens. Nowadays, there are many brands and varieties of glasses. Glasses are usually classified according to the material, structure, and use of the lens. Most of the glasses in the prescription are classified by structure. Nowadays, single vision glasses and multi-focal glasses are mainly used, and multi-focal glasses include bifocal glasses, three-lens glasses, and progressive multifocal lenses.
KoalaEye Gold rimless glasses - Lilac
The rimless frames focus on lightness, reducing the pressure on the wearer and increasing comfort. The rimless era says goodbye to the shackles of the frame. The pair of glasses are suitable for all face sizes. Free and comfortable, unique texture makes your temperament unique, gentle elegant, and charming. The radian is beautiful, and the craft is exquisite, in accordance with the feminine soft and gentle characteristic. They are not easy to lose, not easy to damage, durable. They reduce the contact area with the skin, safe and comfortable.
When should I use blue light glasses?
Most of us spend a few hours a day in front of a screen. Because so many people work on a computer all day, many people wear blue glasses in the office. At the same time, many American high school and college students spend hours a day on their computers and could benefit from blue light glasses.
Eye problems that may occur while driving.
Visual fatigue and xerophthalmia: when driving, the spirit and eyes are in a highly tense state, reducing the blink of an eye, which will easily cause eye fatigue and xerophthalmia. Flash glare -- car headlights and city light pollution -- can cause serious damage to the eyes. UV damage: UV radiation is strong when driving in the daytime, especially in the plateau and snow weather. Nocturnal myopia: nocturnal light is insufficient, so it can make the eye pupil dilate, causing nocturnal vision to drop influence driving safety.
What Are the Disadvantages of Progressive Lenses?
In this section, we will show you some progressive lenses disadvantages.
1. You must learn how to see through the lens. Since there is no visible line in progressive lenses, you may need one or two weeks to learn the correct way to look through the lens.
2. Temporary vision distortions. The lower part of a progressive lens is magnified since it is designed for reading. So, when you look downward when stepping off a curb or walking upstairs, your feet may appear larger through the progressive lens so that it is difficult for you to gauge your step.
3. Progressive lenses are expensive than traditional glasses. So, when you purchasing the progressive lenses, you can compare several different optical stores. In addition, Koalaeye Optical, a professional glasses provider, offers various glasses including cheap progressive lenses, sunglasses, blue light glasses, and so on. Besides, it provides the free shipping service.