The sunglass lens tint reduces visible light and provides effective protection against sun glare.

1. The Categories Of Sunglasses Ultra
Violet Protection (UV)

2. The sunglass lens tint reduces visible light and provides
effective protection against sun glare. Renowned
manufacturers ranked lenses into different categories
depending on light conditions. To find the category to
which a pair of sunglasses belongs, you just look at
the interior of the frame. Ranking ranges from 0 to 4
according to European standards:

3. Category 0: Passes 80% to 100% of brightness. Clear
or slightly tinted, perfect for indoors and outdoors with
cloudy weather.
Category 1: Passes 43% to 80% of brightness. Slightly
tinted glasses: the perception of the luminosity is
reduced. Good for cloudy days and in the city.
Category 2: Passes 18% to 43% of brightness.
Moderately tinted lenses: light perception average.
Particularly suitable for summer.

4. Category 3: Let go 8% to 18% brightness. Dark glasses:
strong sunlight. Very suitable for southern climates,
water reflections, beaches and mountains.
Category 4: Passes 3% to 18% light. Very dark glasses:
exceptional solar luminosity (not recommended for
driving). Ideal for high mountains and glaciers.

5. UV filtering occurs through appropriate lenses
regardless of the level of "darkness" of the tint. It's
not necessarily the darkest glasses that best protect
the eyes, but sunglass lenses made with materials of
high quality, high capacity UV-ray filters.

6. The sunglasses with the CE mark comply with all
requirements and directives, and provide adequate
ultraviolet ray protection for the eyes. The CE mark
often etched to the inside of the frame and more
specifically to one arm of the sunglass frame, shows
compliance with safety requirements in accordance
with EU directives. There is no independent body that
inspects each model individually. However, the
famous manufacturers of glasses are often voluntarily
complying with these standards due to their desire to
preserve their global standing and to keep their
reputation intact. You can also check for yourself the
validity of that mark by consulting an expert in the
optical world or simply an optician.

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