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Essilor protects your eyes’ solar resources

 

The human eye possesses natural defenses to protect itself against light, either by closing the pupils or adapting the retina. This protection may however prove inadequate. Essilor has developed a range of filter lenses that can be used to strengthen the eye’s natural defenses.

 

Filter lenses serve a dual purpose:

• to reduce the level of intensity of the light that reaches the eye

• to eliminate harmful rays

 

Coloring

 

There are two techniques to color lenses: vat-dyeing and surface treatment. These techniques are applied in different ways, depending on the type of lens.

 

Specific coloring procedures according to the type of lens.

 

	Vat-dyeing	Surface treatment
Organic lenses	- Pigments integrated into the monomer. - Addition of UV-absorbing chemical agents to enhance protection against these rays.	- The lens surfaces are saturated by colored pigments. - Immersion of the lens in a solution containing the pigments.
Mineral lens	Manufactured directly from pallets of tinted material	Application of a light-absorbing coating on one face of the lens.

 

Variable tint lenses

 

Variable tint or photochromic lenses react to the sun’s rays:

• they darken under the effect of UV rays

• they lighten under the effect of heat.

In an identical UV environment, photochromic lenses tend to become darker as the temperature falls. The photochromism is made possible by the introduction of light-sensitive substances into the material (both mineral and organic) during manufacture.

 

Polarizing filters

 

When the sun’s rays hit a smooth, horizontal surface they cause glare, which can be uncomfortable for the eye. This reflected light is polarized and can be eliminated by a filter.

Sunglass lenses may include a filter that blocks polarized light. This results in:

• better perception of reliefs and contrasts

• greater visual comfort in areas where reflected light is intense (sea, mountains, road surfaces etc.)