What does the Drop Ball Test have to do with the eyewear industry?
FDA mandates that eyewear products must ensure their safety. Impact resistance is a basic norm for binding glasses and/or lenses in the United States. The FDA does say that a drop ball test must be performed on every glass lens for prescription use. The FDA-regulated eyewear products are common in the everyday lives of the public, and the FDA considers impact-resistant lenses to be an important part of the safe design of these devices. Today, safety lenses are rarely mentioned in our sales, but in the 1990s, when resin lenses first entered the Chinese market and glass lenses still dominated the market, safety lenses were a pretty important concept. At the time, the hardening technology has not been upgraded, and the resin lens is easy to wear out than the glass lens. The eyewear industry is relying on lightness, safety (anti-impact), comfort (anti-ultraviolet) step by step to achieve the market share of resin lenses from 1% to 100%.
Design principle of progressive multifocal lens
For the same piece of the lens, the top is used to see far, the bottom is used to see close. The upper and lower degrees are different.
There is not a sudden change in the distance degree fixed above the lens to the near degree fixed below the lens, but a gradual transition between the two through gradual changes in refractive power, which has special benefits over common bifocals or trifocal lenses.
RIVBOS Polarized Sports Sunglasses for Driving
TAC Polarizing Lenses - RIVBOS lenses are made from cellulose triacetate (TAC) material. TAC has quality optical properties that prevent the shrinkage of PVA polarized light film and has high strength surface scratch resistance. They help restore the original color, eliminate reflected and scattered light, and provide perfect eye protection. Rivbos frames are made from durable TR90 material. These polarized sunglasses feature flexible, stress-resistant frames that are able to withstand pressure without breaking. Whether it's sports or casual, you can show off your unique style.
What is the best lens material?
Trivex is a special material from PPG. Compared with PC lenses, the refractive index is lower (only 1.53) but the Abbe number is higher (up to 45), which results in smaller dispersion and better image quality. At the same time, the impact resistance of the Trivex lens is 10 times higher than that of the PC. It is the only explosion-proof safety lens that can withstand external force twists and turns in the market at present.
Recommended Glasses for Heart Shaped Face
Here, we will show you some recommended heart shaped face glasses.
Circular frames: The first pair of glasses for heart shaped faces we want to recommend is the circular frame glasses. Round frames provide contrast and can help to soften your angular features. They draw attention to your eyes and cheekbones and away from your chin or forehead.
Rectangular frames: rectangular frames are able to provide balance on heart shaped faces. They add structure to curvy features and can make your forehead appear narrower. These rectangular frames provide a professional look and don’t draw much attention to themselves.
Rimless and semi-rimless frames: as for glasses for heart shaped faces, rimless and semi-rimless glasses are recommended. Rimless glasses don’t highlight anything and let your facial features speak for themselves. Semi-rimless glasses can help balance your forehead and draw attention downwards to your jawline.
Do Blue Light Glasses Work?
When wearing blue light glasses, you may ask whether the blue light glasses really work. In fact, many users have the same troubles. To answer this question, some researchers have made research and have found that blue light glasses make it possible to remain fully engaged in our technologically advanced world, without taking on the negative effects of blue light.
With the blue light blocking glasses, you can focus on the task at hand without negative effects. Besides, with the blue light blocking glasses, you can even sleep well and reduce eye strain. You can also test your blue light glasses are real.
Disadvantages of Progressive Lenses
It takes time to adapt to the lenses. It can generate poor visual resolution (blur). There is also a geometric distortion of the field of view. Some of the problems with advanced progressive lenses occur when walking up and downstairs. Because the reading correction is at the bottom, the staircase may look like a rebound. However, this is all done to accommodate your progressive lenses, and within about two weeks the shortcomings should disappear. It takes some time to get used to progressive lenses. Changes in vision occur at the rim of the lens, leading to slight changes in peripheral vision. For some people, change is a little difficult. Because the first wear of progressive lenses may occur slight dizziness, shaky walking. One should be careful when they exercise or go Up and down the stairs. Because the sense of space changes, the distance judgment of the object, the sense of depth changes, people who first wear should not immediately drive or do strenuous exercise. When looking closely, the eyes need to turn down, they have mild discomfort in the eyes. The object becomes blurry when they look at it through a blurred area around the lens. Therefore, new wearers turn their heads more and turn their eyes less when they see things and try to use the far, near, and middle distance areas to see the object.
