So How Do Sunglasses Work?

!±8± So How Do Sunglasses Work?

There are two reasons to wear sunglasses. The first reason is if you don't like the bright sun shining in your eyes, as the dark surface of the sunglasses helps to block out bright light and make the world appear darker. The second is that the sun's ultraviolet rays can be harmful in the long term, causing all sorts of problems with your eyes including loss of eyesight and eye cancer. Good sunglasses protect against this, as their lenses filter out most of the harmful UV rays.

So how do sunglasses work? The darkening effect is a very simple one: looking at the world through tinted lenses makes it seem darker to you - even though the effect is really just an optical illusion, it can help you if exposure to bright sunlight tends to give you a headache or cause you to squint.

The UV-filtering effect, however, is more complex. UV-filtering lenses are coated with special chemicals that allow light to pass through them, but reflect away UV. UV rays are basically high-frequency light waves, which means that the chemical structure has to be built to deflect higher frequency light while allowing through lower frequency light. This is difficult science, and the materials needed to do it are expensive.

The most complicated sunglasses of all are prescription sunglasses. These are sunglasses that not only protect from light and UV, but also work like normal glasses to correct your eyesight. For this to work, it requires that normal vision-correction glasses are taken, tinted and coated with UV-reflecting chemicals - a complicated three-step process. However, all the ingredients work together flawlessly, to produce sunglasses that are wearable by people who need their vision corrected all the time. It is even possible to buy clear tinted lenses that fit over the top of your normal glasses, effectively a do-it-yourself way of making prescription sunglasses.

So How Do Sunglasses Work?

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Fitovers Eyewear - Nagari Collection - Torana - Amber Sky/polarized Amber - Designed to Fit Over Small Oval Shaped Frames Not Exceeding 143mm X 42mm - 5 - 5/8" X 1 - 1/2"

!±8± Fitovers Eyewear - Nagari Collection - Torana - Amber Sky/polarized Amber - Designed to Fit Over Small Oval Shaped Frames Not Exceeding 143mm X 42mm - 5 - 5/8" X 1 - 1/2"

Brand : Fitovers | Rate : | Price :
Post Date : Nov 06, 2011 18:51:14 | Usually ships in 1-2 business days

Splotch GuardTM An oleophoibic treatment that prevents fingerprints and smudges from adhering to the surface of the lens Duo Hard CoatTM Provides multiple impact and scratch resistant treatments protecting your lenses for years to come. Flash-ReflectTM A subtle flash mirror treatment that reflects bright light away when in intense light conditions. Flash-ReflectTM gives the lenses a glass-like appearance and hides your prescription eyewear. BlueLight FilterTM All PDXTM Lenses filter out varying degrees of blue light. PDXTM Polarized Amber 16: Luminous Transmittance Value (Tv) = 16% This lens blocks 99.9% of all reflected glare while allowing 16% of visible light to pass through the lens to your eye. PDXTM Amber lenses have a medium to dark brown/yellow tint that is ideal for bright sunny days and overcast conditions. PDXTM Polarized Gray 15.5: Luminous Transmittance Value (Tv) = 15.5% This lens blocks 99.9% of all reflected glare while allowing 15.5% of visible light to pass through the lens to your eye. PDXTM Gray lenses have a medium to dark tint that allow colors to be seen in their most natural state.

• Designed to fit over small oval shaped frames not exceeding 143mm x 42mm - 5 - 5/8" x 1 - 1/2"
• PolarvueTM Polarized Lenses
• Wrap around 100% UVA & UVB Protection
• Hypo-allergenic Crystal NylonTM Frame
• Helps prevent Cataracts

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Fitovers Eyewear - Nagari Collection - Torana - Dark Charcoal/polarized Grey - Designed to Fit Over Small Oval Shaped Frames Not Exceeding 143mm X 42mm - 5 - 5/8" X 1 - 1/2"

!±8± Fitovers Eyewear - Nagari Collection - Torana - Dark Charcoal/polarized Grey - Designed to Fit Over Small Oval Shaped Frames Not Exceeding 143mm X 42mm - 5 - 5/8" X 1 - 1/2"

Brand : Fitovers | Rate : | Price :
Post Date : Oct 28, 2011 23:00:46 | Usually ships in 1-2 business days

Fitovers Eyewear - Nagari Collection - Torana - Dark Charcoal/polarized Grey - Designed to Fit Over Small Oval Shaped Frames Not Exceeding 143mm X 42mm - 5 - 5/8" X 1 - 1/2"

Splotch GuardTM An oleophoibic treatment that prevents fingerprints and smudges from adhering to the surface of the lens Duo Hard CoatTM Provides multiple impact and scratch resistant treatments protecting your lenses for years to come. Flash-ReflectTM A subtle flash mirror treatment that reflects bright light away when in intense light conditions. Flash-ReflectTM gives the lenses a glass-like appearance and hides your prescription eyewear. BlueLight FilterTM All PDXTM Lenses filter out varying degrees of blue light. PDXTM Polarized Amber 16: Luminous Transmittance Value (Tv) = 16% This lens blocks 99.9% of all reflected glare while allowing 16% of visible light to pass through the lens to your eye. PDXTM Amber lenses have a medium to dark brown/yellow tint that is ideal for bright sunny days and overcast conditions. PDXTM Polarized Gray 15.5: Luminous Transmittance Value (Tv) = 15.5% This lens blocks 99.9% of all reflected glare while allowing 15.5% of visible light to pass through the lens to your eye. PDXTM Gray lenses have a medium to dark tint that allow colors to be seen in their most natural state.

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Fitovers Eyewear - Jett Collection Designed to Fit Over Medium Oval Frames Not Exceeding 143mm X 39mm - Gunmetal/polarized Grey with Blue Mirror Coating

!±8± Fitovers Eyewear - Jett Collection Designed to Fit Over Medium Oval Frames Not Exceeding 143mm X 39mm - Gunmetal/polarized Grey with Blue Mirror Coating

Brand : Fitovers | Rate : | Price :
Post Date : Oct 16, 2011 00:00:57 | Usually ships in 1-2 business days

The Jett Collection - Designed to be worn over medium, oval or round prescription eyewear frame shapes not exceeding 143mm x 39mm. They come standard with PDXTM PolarDynamiXTM Polarized Lenses and Side Shields, Wrap around 100 % UVA & UVB protection, Hyper-allergenic Crystal NylonTM Frame and helps prevent Cataracts.Fitovers Eyewear is specifically designed to be worn right over your prescription eyewear. Fitovers Eyewear frames are also popular for use as "wear alone" sunglasses. With polarized glare-blocking protection and full wrap-around styling, Fitovers Eyewear is the perfect sunwear solution for your favorite outdoor pursuit. An Integrated Brow Bar prevents light that enters from above and aids in the Fitovers Eyewear "float factor"v - a feeling that the Fitovers Eyewear frame is literally floating above your prescription frame.PCX PolarDynamix lenses eliminate glare and help protect your eyes from harmful UV rays. They also offer natural color definition, superior visual acuity and enhanced contrast. Duo Hard Coat - Provides multiple impact and scratch resistant treatments, protecting your lenses for years to come. Flash-Reflect - A subtle flash mirror treatment that reflects bright light away when in intense light conditions. Flash Reflect gives the lenses a glass-like appearance and hides your prescription eyewear. Splotch Gard - An aleaphobic treatment that prevents finger prints and smudges from adhering to the surface of the lens.PDX POLARIZED GRAY maintains true color definition in all conditions regardless of varying light. Transmitting all colors equally, PDX Gray lenses are ideal for driving or any general purpose outdoor activity where annoying glare is present. PDX Gray lenses are ideal for those who are light sensitive or suffer frame migraines.

• Focus on comfort and style - Tailored frame shape to ensure a perfect fit
• Integrated brow guard with built-in polarized side lenses
• Crystal nylon flexible frames
• PCX PolarDynamix with Duo hard coat, Flash Reflect and Splotch Guard
• Includes clip-on case, microfibre cleaning cloth and an adjustable neck cord

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Fitovers Eyewear - Nagari Collection - Yamba - Satin Black/polarized Grey - Designed to Fit Over Small Oval Shaped Frames Not Exceeding 143mm X 42mm - 5 - 5/8" X 1 - 1/2"

!±8± Fitovers Eyewear - Nagari Collection - Yamba - Satin Black/polarized Grey - Designed to Fit Over Small Oval Shaped Frames Not Exceeding 143mm X 42mm - 5 - 5/8" X 1 - 1/2"

Brand : Fitovers | Rate : | Price :
Post Date : Oct 09, 2011 05:20:27 | Usually ships in 1-2 business days

Fitovers Eyewear - Nagari Collection - Yamba - Satin Black/polarized Grey - Designed to Fit Over Small Oval Shaped Frames Not Exceeding 143mm X 42mm - 5 - 5/8" X 1 - 1/2"

Splotch GuardTM An oleophoibic treatment that prevents fingerprints and smudges from adhering to the surface of the lens Duo Hard CoatTM Provides multiple impact and scratch resistant treatments protecting your lenses for years to come. Flash-ReflectTM A subtle flash mirror treatment that reflects bright light away when in intense light conditions. Flash-ReflectTM gives the lenses a glass-like appearance and hides your prescription eyewear. BlueLight FilterTM All PDXTM Lenses filter out varying degrees of blue light. PDXTM Polarized Amber 16: Luminous Transmittance Value (Tv) = 16% This lens blocks 99.9% of all reflected glare while allowing 16% of visible light to pass through the lens to your eye. PDXTM Amber lenses have a medium to dark brown/yellow tint that is ideal for bright sunny days and overcast conditions. PDXTM Polarized Gray 15.5: Luminous Transmittance Value (Tv) = 15.5% This lens blocks 99.9% of all reflected glare while allowing 15.5% of visible light to pass through the lens to your eye. PDXTM Gray lenses have a medium to dark tint that allow colors to be seen in their most natural state.

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Mont Blanc Womens Fitover MB282S 34F Sunglasses

!±8± Mont Blanc Womens Fitover MB282S 34F Sunglasses

Brand : Mont Blanc | Rate : | Price : $359.00
Post Date : Sep 28, 2011 03:51:38 | Usually ships in 24 hours

Mont Blanc Womens Fitover MB282S 34F Sunglasses

The Mont blanc Eyewear collection produced by Marcolin once again perfectly interprets the values and personality of the brand.Mont blanc eyewear, with its 100 year history as a maker of sophisticated, high quality eyewear, is today a purveyor of exclusive products which are the result of craftsmanship, quality design and tradition. Each frame bears a sense of eternity through a modern and contemporary spirit, retaining an exceptional coherence with the principals and philosophy that have made Montblanc one of the leading luxury brands. Mont Blanc eyewear stands out for its unique design, and the use of precious materials.These eyewear accessories redefine the elements of timeless class, in which the use of exclusive materials such as titanium and carbon fibre represents todays innovative trends in eyewear.The meticulous care put into the smallest detail is another of the more evident qualities in the Mont blanc Eyewear collection.

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Fitovers Eyewear Glides Sunglasses with Swarovski Elements on temples (Brown, Amber)

!±8± Fitovers Eyewear Glides Sunglasses with Swarovski Elements on temples (Brown, Amber)

Brand : Fitovers | Rate : | Price : $59.95
Post Date : Sep 21, 2011 07:57:27 | Usually ships in 1-2 business days

Fitovers Eyewear Glides Sunglasses with Swarovski Elements on temples (Brown, Amber)

The Glides Fitovers with PDX Yellow lenses are designed to be worn over small prescription eyewear frame shapes. These lenses maintain true color definition in all conditions are ideal for driving or any general purpose outdoor activity where annoying glare is present.

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