How Do Varifocal Lenses Work?
Varifocal lenses work by changing power from the top to the bottom of the lens. Moving your eyes up and down, the varifocal lens will give you clear vision at all distances you need. This means if you are using a cash machine, you would be able to view the keys, screen, your card and then continue to walk down the street.
Evolution of hard coating technology
The first generation of the use of hard coating technology began in the early 1970s, the quartz material is deposited on the surface of a resin lens under vacuum conditions, form a very hard anti-wear film. However, due to the mismatch between the thermal expansion coefficient and the film base material, it is easy to delaminate and crack the film. Instead, it forms the mottle on the surface of the lens, and the effect is not optimal.
The second generation of hard coating technology is the use of the 1980s. The surface of the resin sheet is coated with a material with high hardness and not easy to be brittle and cracked by an immersion process. At this time, anti-reflection coating lenses had appeared and gained the recognition of consumers, but the mismatch between adding hard coating and anti-reflection coating still caused serious lens wear.
The third generation of hard coating technology was developed in the 1990s, mainly in order to solve the problem of wear resistance after coating resin lenses with an anti-reflection film. The hardened material evolved into a polymer organic matrix material.
Fourth-generation coating technology is dominated by silicon atoms, in which the hardened solution contains both organic substrates. It contains inorganic ultrafine particles, including silicon elements, which make the hard coating not only tough but also hard.
How much should a pair of prescription glasses cost?
Speaking of glasses, everyone's first feeling may be that it is not cheap to have a pair of prescription glasses. Just such a small pair of glasses, ranging from a few hundred dollars to a few thousand dollars. Why is the difference so big? So some people go online to buy glasses for dozens of dollars as if they look the same. But is it actually the same? There are a lot of differences between the glasses for dozens of dollars and for thousands of dollars, apart from the price. Also, you should be responsible for your own eyes.
Better glasses brands will adopt better designs to ensure beautiful appearance and structural safety, and have stricter quality standards. At first, these glasses are not cheap because the cost has increased a lot. In addition to the brand, different materials, process requirements, and mass production scale will also affect the cost and thus the final selling price. As for the question of what price glasses to choose, my suggestion is to choose the high-priced one within your budget. So, to choose a suitable pair of glasses, what aspects need to be considered?
Is it safe to buy contact lenses online?
Today's optometry is not a simple measurement of your degree. Through some professional instruments, they check the health of your eyes to see the health of your eyes. Is it appropriate to wear contact lenses at present? If there is inflammation in the eyes, it is forbidden to wear contact lenses, and if you wear them, it will cause harm to the eyes. If you buy online, you can't enjoy professional eye examination, try on, test, and other professional inspection and matching services that you can enjoy in professional stores, nor can you enjoy professional wearing and nursing guidance from professional staff. People often overlook eye problems that may result from the wrong choice of contact lenses, which are often overlooked by consumers.
Because of its unique lightness, and its unique materials, the American space agency, NASA, took a fancy to it and designated it as space special glasses. Since 2000, it has accompanied astronauts on 35 space missions. With no frames, screws, or hinges, this is the new look that will forever be memorized as the Rimless Titan Minimal Art（TMA） glasses, which weigh 1.8 grams. In order to reduce weight and improve comfort, the EmPadsystem patent was invented, which improved the eyeglass beam and nose pad, further effectively reducing the pressure of eyeglasses on the nose bridge and making the eyeglass nose pad easier to clean.
Quality and price have benefits
EyeglassesDepot.com is unbeatable in quality and price.There are two on-site LABS that provide low prices.In reality, other repair sites you may have visited may have used our facilities to repair customers' frames.The cost of repair is ensured to be minimal.
Editor's Pick: Polarspex Polarized Night Driving Glasses
The most popular product on Amazon is Polarspex's line of polarized sunglasses. A wide variety of finishes are available. You'll want to select Night Driving Yellow lenses for your night driving glasses. Affordable and stylish, these glasses feature a plastic frame, metal-reinforced hinges, and plastic polarized lenses designed to block BOTH UVA and UVB rays.