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 Is Anti Reflective Coating?
Anti reflective coating, also known as AR, anti-glare, no-glare, or glare-free coating, can provide benefits to your vision. Anti reflective coating is added to lenses to reduce glare caused by light hitting the back of the lenses to improve your vision and make your eyeglasses more visually attractive.
Anti reflective coating will eliminate all reflections from the front and back surfaces of your lenses. Hence, more light is able to pass through your lenses which improves your vision. At the same time, fewer distractions are visible and the lenses are hardly noticeable, especially in the dark. So, is anti glare worth it? Most people agree that.
When do you need blue-light-blocking glasses?
Anti-blue light glasses are suitable for wearing when using LED digital display devices like TV, computer, PAD, and mobile phone. However, it is not recommended to wear anti-blue light glasses for a long time in daily life, because the anti-blue light glasses filter part of the blue light and the picture will be yellow when viewing objects. It is recommended to wear two pairs of glasses, one pair of ordinary glasses for daily use. A pair of anti-blue light glasses to use for computers and other LED display digital products.
Is there any relation between lens refractive index and lens definition?
First of all, in reality, from the point of view of the immediate situation, there seems to be no correlation. The refractive index is mainly related to the speed of light transmission into the lens. High refractive index lenses can be made thinner, lighter, and the technology required to do this is more sophisticated, so high refractive index lenses are more expensive. But does a high refractive index make the lens clearer? The higher the refractive index of the lens, the lower the Abbe number. The Abbe number is a very important parameter we use to measure the sharpness of the lens, which means that if the refractive index of the lens is high, that is to say, the sharpness of the lens is lower. If you have higher degrees, you can prioritize thinness and choose a lens with a higher refractive index, but don't overdo it.
The Cons of Progressive Lenses
In this section, we will show you the cons of progressive lenses. There are some problems with progressive lenses especially when walking up and downstairs. Since the reading correction is at the bottom, the stairs may appear closer than they actually are. But this problem can disappear if you have adapted to them.
In addition, all measurements must be exact when creating a pair of progressive glasses. The optical center of the lenses must be placed exactly in front of your pupils in order to the lenses to work correctly.
Also, some people may find that it is difficult to adapt the progressive lenses, and it may take a few days to adapt them.
These are the progressive glasses’ pros and cons. If you want to a pair of progressive glasses, Koalaeye glasses are recommended. Koalaeye glasses are stylish and come at a cheap price. Besides progressive glasses, Koalaeye Optical also provides other eyeglasses, such as blue light block glasses, polarized glasses, sunglasses, and so on. So, if you need a pair of progressive glasses, try Koalaeye glasses.
Best Frames For Heart-Shaped Faces
The heart-shaped face should be one of the favorite faces of Asians. It is characterized by a wide forehead, prominent cheekbones, and narrow and pointed lower jaw. This face shape is not balanced up and down in appearance, and the upper part is larger and more prominent than the lower part. Need to wear sunglasses with a wider bottom, which can increase the width of the lower half of the face. The lower mirror foot position also helps to improve this effect. Don't pick a special big style, normal size will do. Pilot sunglasses with a more angular top and bottom can be used to balance the roundness of the heart-shaped face and chin, increase the sense of facial lines, and visually make the face fuller. Retro black round sunglasses, coupled with a handsome choker, highlight the full street casual style. The recently popular 'inverted triangle sunglasses' are also very suitable for heart-shaped faces. The raised angle of the frame can correct the facial lines and add some angularity to the face. The inverted triangle sunglasses also have a retro temperament, and it feels that there is a mysterious demeanor hidden.
Common Problems with Varifocal Glasses
In this section, we will list some common problems with varifocal glasses. The most common problem with varifocal glasses is people being unable to focus on what they need to. Losing focus often leads to some discomforts such as headaches or dizziness when performing tasks that require quick changes in near and middle-distance focus.
Besides, some people also experience a sort of swimming feeling when they are walking. It may be caused by being very aware of the distortions in your peripheral vision as well as the reading portion at the lower part of the lenses.
So, how to use varifocal glasses? The best way is to keep yourself from looking downward as you walk. You may also experience soft focus at the edges of the lenses and need to move your head more to see near objects better.
