Fixed tint lenses
In fixed tint lenses, the shade of the lens does not change. Within this category of sun lens, there are two main types: classic and polarized lenses. Both types come in a range of colour and tints adapted for different intensities of sunlight, while polarized lenses also eliminate glare to give you more comfort and confidence outdoors.
In fixed tint lenses, the shade of the lens does not change. There are two main types of fixed tint lens: classic sun lenses, which are coloured with a pigment to obtain the desired level of shading; and hi-tech sun lenses, which contain a polarized coating and therefore offer full glare protection as well as shielding against bright light. Both types can easily be adapted for corrective lenses.
What are the benefits of a classic fixed tint lens?
Around three-quarters of lenses on the market have a classic fixed tint . The range of these tints is extremely large, giving you plenty of scope for expressing your personality, while also providing lenses adapted for specific activities such as sports.
A number of different methods are used to make classical fixed tint lenses, but they all involve adding a coloured pigment, which can be made light or dark or anywhere in between. This means fixed tint lenses come in a whole range of shades to suit different intensities of sunlight.
The tint of a lens is also responsible for shaping your perception of colours. Different tints filter different elements of visible light, meaning you may see ‘more yellow’ or ‘more blue’, for example. For everyday use, the best choice is a neutral (grey or grey-green) or all-purpose tint (brown). For sports, you may consider a yellow-orange tint, as this helps improve contrast. Blue blocker tints, meanwhile, completely filter out blue light, which has been linked to certains forms of eye damage. Most browns lenses are blue blockers.
Here is an example of recommendations of some tinted lenses for sports :
Why should I choose full glare protection lenses?
“Full glare protection” lenses, also known as polarized lenses, represent the top end of eyewear. While non-polarized fixed tint lenses may provide 100% UV protection and help reduce brightness, they will not stop you being affected by sudden glare. Only polarized lenses offer this luxury and therefore help reduce eyestrain and prevent potential headaches.
What is polarization?
Polarized lenses protect you against polarized light. So, what exactly does that mean? Polarization occurs when the sun’s rays are reflected off a flat surface such as snow, water, glass or the road. This gives off a intense light that, for a brief moment, makes it difficult for us to see. You probably know that feeling of being dazzled by a bright light off a window? That is polarization.
Improving your performance and safety
Thanks to a special film inside the lens, polarized glasses eliminate dazzling glare and increase your visual performance. This is helpful when you’re playing sports such as tennis or golf, when you need to accurately see a ball, or when you’re cycling or walking in bright light. Reducing glare can even prove vital for your safety in activities such as skiing or driving.
Here is a concrete example of what we perceive, with and without polarized lenses when blinding glare occurs on the road:
More than 90% of decisions and reactions made at the wheel of a car depend on good vision, and dazzling glare can significantly alter our perception. In tests, drivers were found to improve their reaction times by a third of a second when wearing polarized lenses. At 80 km/hour (60 miles/hour), this translates to stopping a vehicle 7 metres earlier, which can be the difference between braking safely and having an accident. It is not surprising that people wearing prescription polarized lenses are more likely to say they feel safer driving on sunny days than those with non-polarized prescription sunglasses.
Choose a polarized lens to suit your style
Polarized lenses come in a range of styles. Some help improve colour perception or enhance contrast, while others combine these qualities to provide the very best polarizing performance (more information on Xperio web site).
You can also choose the colour of your polarized lens: brown, grey, grey-green, etc. Or you may like to have a gradient lens or add a mirror finish, which is particularly recommended for skiing. Your lens may even blend polarized and photochromic technologies to stop glare while simultaneously adapting to different sun conditions. This combination is excellent for cycling or running at times when you think the light may change, such as at sunset or sunrise.
Whatever your activity and whatever the season, polarized lenses offer that extra assurance to help you get the most out of life outdoors.
• They may be dipped in a water-soluble dye. The longer the lens is kept in the dye, the darker the shade.
• When the lens is being made, a chemical compound may be added to the molten glass, a process known as through-dying or tinting in the mass.
• Alternatively, a special filter may be added to the lens after production to give it the right tint.
While the first two methods can be applied to fixed or variable tints, the final method is reserved for variable tint lenses. It should be noted that prescription lenses may be thicker at the centre or at the edges, and therefore require a special to ensure the lens is equally shaded across its entire surface.