SUNGLASSES AND STUFF :-)
Protecting the eyes against sun radiations is a must on a hike.
But first a few things to share with you.
Every time a person wants to buy a pair of glasess or sunglasses, I noticed in my 20 +ys of practice they
have no clue about the physics beyond . So a few data about this would be helpful for people to undertand what they are putting in front of their eyes. A first and essential aspect of a lense is it’s quality, which means the main optical features provided by the manufacturer assure no harmful distorsions are imbedded in the material. These distorsions called aberarions are not macroscopic, they are invisible, but are felt after a period of time and people wonder why those headaches, dizziness, eye strains.,,etc.That’ s why always ask about the manufacturer of the lenses. Secondly and more and more important lately is the protection of the lense against 2 main factors:
For outside use,there is the UVA and UVB protection and anti glare reflection.
For inside use:the protection against artificial light, which has a very different spectrum versus the natural light, therefore your brain has to do an extra and continuous effort to translate the light recieved on your retina and translate it to yourvisual cortex to transform the light in the image you see,. For inside use , additionally to the artificial illumination, there is the radiation from LCD emitting devices, laptops, phones, tablets.
You ‘d say “my computer has a lot of screening and filters and options to filter blue radiation and so on”.
Yes, some
have,some don’t. (I personally use light adjustion and blue light filters).But an additional filter is always a good idea. And a much better idea would be to use natural light at your office, if possible.
Long story short, the outdoor offices are the best . 😉
Most modern lenses offer 100% protection against both UVA and UVB. It’ s a must.UVA rays can pass through your eyes and reach the
retina. This may lead to structural changes within your eyes. These can also cause certain eye diseases such as macular degeneration and cataracts. High doses of UVB rays, on the other hand, can cause eye sunburn.
A 3rd category of lenses are the polarised lenses which are much more than usual sunglasses.Actually they are based on a totally different approach of filtering the bothering lights and glares.And most important, they are very helpful for winter outdoor activities, especially when the snow raises the UV index to a very bothersome level.
That’s where polarised lenses come in !
As I have an
“obsession ” for the planet friendly everything, obviously I seek the manufacturers who use materials with the lowest possible impact on our environment.
Olwen is a great choice, because they have this :
For every pair of sunglasses, they plant a baby tree
The little tree will grow, will filte rthe air for you, will give you the oxygen you breathe and a lot ,lot more.
Simple, elegant designs, I have some photos bellow, a few of the choices that felt that soothing effect in my forehead, reducing the eyestrain .
Polarised for men
