LENS COATING
EYE HEALTHCARE – “GETTING THE MOST FROM YOUR GLASSES”
No spectacle lenses, not even glass, are completely scratch resistant. Standard spectacle lens materials, although robust, can be relatively soft when it comes to abrasions. When treated front and back with a clear ‘scratch resistant coating’, it has the effect of ‘smoothing’ over the microscopically irregular lens surface with a super smooth tough coat, minimising any potential abrasion. This is particularly useful on children lenses.
‘Anti Reflection’ (AR) coatings are also widely used, by a process whereby several layers of unique metal oxides are applied to the lens surfaces, giving a characteristic purple or green colour.
A standard untreated lens can give up to 4% (and 7% in Hi Index lenses) of reflection from its surface, but this is reduced to 0.5% when treated, hence
Before your next visit to the Optician take a few moments to consider these important points to maximise the quality and lifespan of your glasses.
Noel McCrystal
BSc.(Hons.)MCOptom.Dip.Sc.V MASv.P