Alter Ego: The Science of Sunglasses

I had to do some research and a presentation about sunglasses some time ago and I did wonder if it was worth blogging. Since there are questions being asked about UV, and style, and polarised, I thought why not. I hope this helps. I tried to condense it to the basics.

"Here comes the science" ......

What is UV?

Ultra Violet Rays (UVR) = UVA + UVB + UVC

They are invisible rays from the sun that affect our eyes and skin. A little bit of sun is actually good for you but in moderation. It can help our bodies with making Vitamin D, strengthen bones and teeth and helps treat psoriasis.

Too much can cause skin cancer, and cataracts hence the need for protection.

UVA, B and C are different wave lengths of the rays, and we are protected from the most harmful UVC through our ozone layer (hence the importance of the ozone layer)

Sunglasses grades of protection

This obviously depends on the make so always ask the vendor if in doubt. Most sunglasses come with a standard UV protection. A moderate / sufficient protection for general use. The European Standards usually has four ratings.

"0" = insufficient UV protection

"2" = sufficient UHV protection

"6" = good UHV protection

"7" = "full" UHVV protection

Do not be fooled that the darker the lens the higher the protection. In fact the filter is just that a film on the lens. The darker the lens the wider your pupil dilates, to enable you to see through them, causing more harm to your eyes if unprotected.

What is Polarised?

Polarised lenses are more expensive then normal lenses. It doesn't really mean they are better then normal glasses. If you are to use your sunglasses for everyday use in town then you wont need polarised. They are mostly and commonly used for outdoor sports where the sun bounces back on reflective surfaces. What is also known as anti glare.

Reducing glare for long haul drivers can ease eye strain. Fishermen use polarised to see under the water surface so they can see the fish and other objects clearer. Photographers use it to create more contrast in their photos.

with / without

without / with

Polarised lenses however do not give you a full protection from glare. They only work at certain angles from the reflected rays and can distort your vision when looking at LCDs ( TV, Mobile / Cell phone screens, etc.)

Now to try

As much as I could go on about face shapes and what suite which best. It is all down to trying on and what is your individual style as well as function. Some might make you look ready for the beach in Miami and others might give that look of shopping in the city or beach party in Ibiza.

I can only say its like clothes and body shapes. If you are pear shaped (big hips) you wouldn't want to make it more noticeable by wearing a tulip skit, you would want to even out your body and elongate. So if you have a round face you don't want to wear round sunglasses or a pair that has more details on the sides to make your face look wider.

Also bear in mind nose bridge and cheeks. For most asians, africans, or any one with a low nose bridge, sunglasses tend to sit too low; or if you have big cheeks / high cheek bones, you find that when you smile your glasses go up as they sit on your cheeks. There are some designers that have a line that cater for this. The bridge on the glasses will be longer to compensate. I know Bottega Veneta and Oakley has an "asian fitting" with some of their glasses.