At EyeBuyDirect, all standard lenses are made of lightweight CR39-resin with a standard lens index of 1.499, coming with a completely scratch resistant coating. Polycarbonate lenses are the lightest material available (optional), and due to its high impact-resistance and durability, it also happens to be an integral material used in making bullet-proof “glass”.
Single vision lenses
Single vision lenses have one fixed focus point or correction over the entire lens area. They can be used for either near, intermediate or distance vision. For instance, glasses for driving or reading are single vision. EyeBuyDirect’s standard free lens is single vision.
A bifocal lens is divided into two sections by a horizontal line, with the upper section of the lens usually used for distance vision, and the lower section used for near vision. These two different focuses in the one lens allow people with myopic or hyperopic conditions to use a single pair of glasses for both long distance and up-close vision.
Also know as varifocals, this type serves the same purpose as bifocals but without the obvious horizontal line segmenting the lenses. It provides a smooth transition between distance and near vision, as well as the capability for viewing intermediate ranges.
Our premium anti-reflective coating is ideal for computer use and night driving. They work by increasing the light transmission through the lenses, providing you with the clearest, sharpest vision at all times. Any great-looking pair of eyeglasses will look even better: people will see your eyes through the lenses, not the light reflection!
No eyeglass lens material – not even glass – is scratch-proof. However, a lens that is treated front and back with a clear, hard coating does become more resistant to scratching, whether it’s from dropping your glasses on the floor or occasionally cleaning them with a paper towel. All our glasses get an anti-scratch coating.
As consumers, our interest in thin and light extends to more than just potato chips and beer – it has impacted eyeglasses in a very significant way. Most eyeglass wearers are nearsighted, and a basic physical property of nearsighted lenses is that their edges are thicker than their centers. The stronger the prescription, the thicker the edges (see lens drawings below). Most of today’s fashionable frames are made of plastic or metal with rims thinner than the lens itself. Aso very popular are rimless mountings, where the lens edges are completely exposed. in either case, the lens edges are highly visible, and thicker edges can detract from the appearance of the eyewear. We provide two kind of thinner lenses: 1.57 called thin and lite, 1.6 called super thin.
Another lens treatment that is beneficial but invisible to the naked eye is ultraviolet (UV) protection. Just as we use sunscreen to keep the sun’s UV rays from harming our skin, UV treatment in eyeglass lenses blocks those same rays from damaging our eyes. Overexposure to ultraviolet light is thought to be a case of cataracts, retinal damage and other eye problems. An ultraviolet treatment is simple and quick to apply to most plastic eyeglass lenses, and it does not change the appearance of the lenses at all.
As opposed to the changeable photochromics, another option in colored lenses is a tint, which remains constant at all times. Tints are available on our glasses with the following colors: brown, grey and green (available 20%, 40%, 60%, 80%). Lighter, fashion tints are used primarily for cosmetic purposes to enhance a wearer’s looks. Darker tints allow the wearer to use the lenses as sunglasses.
Light-adjusting lenses for eyeglasses
Also known as photochromic lenses, are a type of coating that tints lenses but with a unique feature. When indoors, the lens tint will be very light and allow as much light in as possible. However exposed to strong sunlight outdoors, the lenses will get dark depending on the direct exposure to sunlight. Please be advised that these lenses do not get as dark as a typical sunglass and will tint up to approximately 60% darkness.
Bifocal lenses for eyeglasses
are a special kind of lens offered by EyeBuyDirect to customers who want more flexibility with their frames. Bifocals basically have 2 separate parts, the upper part for distance and the lower part for reading. The best thing with Bifocals is it serves a dual purpose for those people who hate changing from distance eyeglasses to reading glasses and vice- versa.
Progressive lenses for eyeglasses
Also known as varifocal lenses or just varifocals, are a type of bifocal but without the line. This lens is usually called no-line Bifocals and is preferred by people who don’t want the line to be obvious on their glasses. They serve the same purpose as bifocals so as to provide both distance and reading vision on a single lens.
Photochromic lenses provide the correct amount of protection for the varying light conditions you experience.
The Photochromic lenses are darken when being exposed to UV (ultraviolet) rays. Once the UV rays are not getting to the lenses (for example by walking indoors), the lenses will gradually return to their clear state.
Thanks to photochromic lenses, eyeglass wearers can purchase one set of glasses that will allow them to see inside, as well as reduce the glare of the sun when outdoors
Important facts are:
- Clear as an ordinary lens indoors and at night
- Block 100% of sun’s harmful UVA & UVB rays
- Available in Gray or Brown
- Because photochromic compounds fade back to their clear state by a thermal process, the higher the temperature, the less dark photochromic lenses will be. This thermal effect is called “temperature dependency” and prevents these devices from achieving true sunglass darkness in very hot weather. Conversely, photochromic lenses will get very dark in cold weather conditions, which make them more suitable for snow skiers than beach goers while outside.
Launched in 2005 and emerging today as a major player in the global online retail sphere, EyeBuyDirect.com is a prescription eyewear website offering an extensive range of high quality, affordable frame and lens packages. The site offers its budget-conscious and style-savvy shoppers a fast, simple and efficient way to browse an extensive online catalogue, and enables them to purchase eyewear from
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