The other morning I went for a long trail run and at the same time field tested a new range of AMO lenses.The weather was humid and overcast and I was using a new pair of clear photochromic lenses which are ideal for the trials.
The problem was, as I ascended the mountain near my house, on the trails into the clouds the lenses of the sports sunglasses started to fog up.
The lenses I was testing did NOT have an antifog coating which is normal for most sports sunglasses and this got me thinking if antifog coatings on sports sunglasses are really worth it.
What is an antifog coating?
An antifog coating is a treatment that is put on the surface of the lenses which prevents condensation and the formation of small droplets on the surface. For more information see this link
Antifog coatings were first developed by NASA in 1961 during the Gemini Space project for use on their astronauts space helmet visors.Antifog coatings have been around for a long time and it is common to see antifog on swimming and ski goggles.
However, it is rare to find antifog coatings on sunglasses, especially sports sunglasses.Antifog is by no means proprietary or special technology despite what some sports sunglasses companies marketing would have you to believe.
For sports sunglasses, it is applied during the manufacturing process and is similar to an oil film on the surface of the lens.An antifog treatment renders at the surface of the lens hydrophilic which stops droplets of water forming on the lens. It does this by preventing the buildup of water vapour molecules such that your vision stays clear and will not fog up the lens.
Do antifog coatings work? The simple answer to this is yes.
However, the effectiveness of the antifog coating reduces over time especially if the lenses are exposed to a detergent which breaks down the antifog surface layer.This means that although the first few times antifog will work, after a while they are less affective and after a certain period the antifog coating no longer exists.
All AMO sunglasses (as standard) have antifog coatings on all their lenses. The second reason for this blog, was because the other day and a friend of mine was talking to me about fogging up of sunglasses during a bike ride and saying that he had never had a pair of sunglasses like his AMO sunglasses that did not fog up on the bike. (Credit to Mo Devlin).
During my recent field test of the new lenses it became clear to me that I didn't realise the antifog benefits of my AMO sunglasses lenses which have (as standard) anti-fog coatings when they fogged up to a point I had to remove them from my face.
For me, it became apparent that I was enjoying the benefits of these antifog coatings without actually realising it. I guess it's a fact of life that you don't appreciate something until you lose it!
Do all sports sunglasses have antifog coatings? The simple answer to this is no.
There are many reasons for this but I will summarise it as follows:
1. Most people do not need it. However, I would say if you are an cyclist or a runner and go out in the early morning or train in different micro-environments then you will need it.
2. It is more costly. It is true that antifog lenses for sport sunglasses are more expensive (as it is an additional manufacturing process) but not significantly so. The small extra cost is therefore good value.
3. The benefits of an antifog coating fade over time. There is no denying this. This is especially so if you clean your lens is in a strong detergent. That said, my AMO sunglasses antifog coatings seem to work quite well and I have been using them over a year now.
So are antifog coatings worth the money?
In my view, it is a no-brainer, the cost increase is very minimal and the benefits can be substantial so therefore why not! Antifog coatings are not just useful for trial runners but are especially useful for cyclists and mountain bikers.
This is because these people quickly transition into different micro-environments where there can be low and then high humidity and rapid temperature differentials which accelerate the anti-fogging process.
So therefore don't accept second-best and make sure your sport sunglasses have a antifog coating as standard.
This is my view, please let me know your views on the above issue.
Tim Hallworth is an endurance athlete and multiple ironman and the co-founder of AMO sunglasses.
Are you can find more blogs about sports sunglasses at the following web page http://www.amosunglasses.com/latest/blog