The working principle of driving glasses
The driving glasses are designed according to the polarized angle and radian of the lens and the principle of precision optics. It can only let the beneficial light pass through, and other light sources, like strong sunlight, car headlights, and other light sources are filtered, to eliminate the interference of external light, and avoid the appearance of eye-catching, dazzling, and other situations. That's basically how the driver glasses are designed.
How to choose the right glasses for myopia?
Nowadays, people are nearsighted, and they usually think of going with a pair of glasses. However, only from the media, we continue to see that there are substandard myopia glasses and frames in the report, so how should we choose when we buy glasses? How can I match a pair of suitable and high-quality glasses? Different glasses shops vary greatly from optics technology to the quality of lens frames, so different shops have different prices. Faced with a variety of glasses, how should we choose? Generally, we can look at these four standards. First, take a look at whether the eyewear company has obtained a production license for eyewear products. Second, see if the optometry equipment and testing instruments of the glasses companies have qualified marks. Third, see if the optometry and production staff are certified to work. Forth, look at whether the glasses have a conformity mark (certificate). The four certificates of eyewear companies are the prerequisite to ensure the quality of glasses.
Features of progressive lenses
With the proper head position, the wearer can have a clear and continuous vision at all distances from the distal point to myopia through the progressive lens. When the eye moves from one area of vision to another, the eye adjustment process is natural and smooth, without any visual fluctuations. With natural vision and better adaptability, it is in line with physiological optics. The mid and near vision area is relatively small: Some wearers may feel that the gradient area of the progressive lens is smaller, which limits the width of the saccadic eye and requires increased head movement in order to achieve the same reading range. At medium and short distances, the wearer needs to coordinate certain head movements.
What Are Varifocal Glasses?
Varifocal glasses, also known as varifocals, varifocal lenses, PALs, or progressive lenses, have a gradual change in strength from the top of the lens to the bottom with multiple focal points in between. This allows you to see all distances and focus points through just one lens. Varifocal lenses are typically used when you have two prescriptions, one for distance and one for reading.
There are three regions of a varifocal lens which are distant zone, intermediate zone and, near/reading zone. Usually, the upper portion of the varifocal lens is the distant zone and the bottom portion of the varifocal lens is the near or reading zone.
One of the benefits of varifocal glasses is that you do not need to prepare 2 separate pairs of glasses or need to switch between frames for different vision needs.
What are prism glasses?
What is a prism? A prism is a solid object with a cross-section along its entire length. If you cut across something, you'll come across a section that's been cut, and that's a cross-section. The upward section is a prism. If you have double vision, you can add a prism prescription to the lens to form prism glasses. It can help keep your eyes focused and greatly improve your vision. In most glasses, prisms are used primarily to change double vision and are useful for image correction. They can aid in position correction.
What is the best lens material?
Early lenses were made of natural materials because they were easy to get. But natural materials have obvious drawbacks. According to records of the Qing Dynasty, Emperor Yongzheng wore crystal glasses given by the imperial court, which greatly improved the efficiency of reading documents. However, because of the cold nature, the crystal will make the temperature around the eyes low when wearing, and part of the crystal lens has color so that the light into the eyes becomes soft.
What Are Progressive Lenses?
Progressive lenses are designed for people who are over 40 years old. It is a blended multi-focal lens with distance correction at the top, intermediate in the middle, and reading at the bottom. The goal is for the lens to work how your eye naturally works to let you see things both close up and far away.
Progressive lenses are made with an hourglass shape so there is some blurriness on the outer edges, but since it gives you your full range of vision, it is generally better than a bifocal despite being similar.
