It is important to use sunglasses that are optimally tailored to the circumstances with the internationally valid and medically recommended UV filter of 400nm in order to avoid painful irritation of the eye and pathological late effects. Before using sunglasses without a UV filter, you should do without one entirely. So here is a clear plus on the benefit side, since matching sunglasses are not only a very fashionable summer accessory, but also promote health.

UV filter & tint

Dark tinted sunglasses cause the pupils to open wider than they would without. The tinted lenses reduce the incident light. If there is no UV filter, large amounts of UV radiation can now penetrate the eyes unhindered and cause directly noticeable damage, but also long-term damage, the effects of which only appear after years and decades.

However, this applies not only to days with obvious sunshine, but also to cloudy days. UV rays also penetrate clouds. The UV radiation is only stopped by appropriate UV filters or by opaque and tightly woven clothing or objects with a corresponding effect.

In addition to the traditional shades of brown and gray, there are also other colors and shades in the standard repertoire.

Colors & meaning

The colors have different effects on the performance of the eyes, as they not only absorb the strength of the sunlight, but also change colors, or even swallow them and thus change and irritate our visual behavior.

Green, gray and brown tones falsify the color impression the least and are the traditional sunglasses colors next to black.

Yellow tones increase the contrast, but let a lot of UV light through, which is especially good for nighttime car journeys.

Red and orange improve visibility, increase the contrasts in nature and the environment becomes more three-dimensional. The retina is well protected from the sun's rays.

Blue tones distort the color rendering, orange objects in traffic blur and their warning and luminosity is lost.

Celine glasses are very popular these days in US. People love to wear them throughout the year because of their stylish designs, beautiful colors and UV protection quality. You may have a look at this link and find the variety of various Celine glasses, https://pretavoir.us/collections/celine-glasses.

Medical benefit

The medical and health benefits of sunglasses are as follows;

• Without adequate sunglasses, one is directly exposed to the sun's rays with UV radiation. The eyes have the possibility to contemplate the world by contracting the pupils or through between the eyelashes.
• Nevertheless, a lot of light and radiation hits the lens and cornea. Sunglasses without a UV filter will reduce the amount of sunshine, but the UV radiation could penetrate unhindered and cause damage.
• In addition to the directly noticeable effects of too much sunlight, such as headaches, dark spots on the retina, sunburn on the cornea, eyelid and lens, there are a number of long-term effects that only occur in old age when too much UV radiation has damaged the eye for years has.
• Unfortunately, this damage is usually recognized too late. Unless the sensitivity to light and frequent foreign body sensation often occurs after outdoor activities.
• Damage such as cataracts, clouding of the lenses, can be operated on, while other long-term damage such as blindness, tumors or age- related macular degeneration (AMD) are irreversible.
• In addition, there are other corneal opacities, eye irritations, such as the feeling of foreign bodies are annoying and can also lead to conjunctivitis and corneal inflammation, or be part of the protoceratids.

Protoceratids occurs roughly between 3-12 hours after exposure to excessive sunlight and UV radiation. The symptoms are pain in the eyes, the feeling of 'sand in the eyes', excessive lacrimation, reactive skin inflammation, redness or conjunctival swelling, inflammation of the cornea, a blepharospasm, which is characterized by compulsive closing the eyes by an increased sensitivity to light and light vision problems.

UVA, UVB & glare protection

The lens and cornea, like the skin of the eyelids, can suffer from sunburn and are mainly damaged by shorter-wave UVB rays. More than half of the UVA and UVB rays hit the lens and cornea, some are absorbed in the eye itself, while about 1-2% penetrates further inside.

The coloring is described in four anti-glare categories. Category 1 with 20-57% tint and 2 with 57-82% for overcast days or the normal glare protection for summer days.

Category 1 is under 20% while 3 with 80-92% should be suitable for water surfaces, beaches and mountains and 4 with 92-97% are made for high mountains and glaciers, while they are unsuitable for road traffic.

In order to protect the eyes as optimally as possible from solar radiation and UV light, the glasses should be large enough to protect the eyes from lateral radiation and also from sun rays falling from above and below.

This also includes reflections that could hit the eye. In addition, the frame should be narrow enough not to seriously restrict the field of view. Overall, this means that the glasses should at least reach the eyebrows and also the edge of the face on the sides to ensure adequate protection.

CAT marking means

CAT, the abbreviation for Categories, describes the tint of the sunglasses and their darkening effect, whereby 0 is hardly tinted, while 3 is suitable for water surfaces, beaches and mountains, 4 on the other hand for high mountains and glaciers. These are not suitable for road traffic. These categories have nothing to do with protection against UV radiation.

How to recognize sunglasses with UV protection?

The US has had CE marking for sunglasses since 1995. The DIN standard ISO 12312-1: 2013 describes the US minimum requirements for sunglasses, which require the blocking of UV rays up to 380 mm.

The affixing of CE and the inscription ISO 12312-1 on the bracket means that the manufacturer has complied with this standard during production. However, there is currently no instance that checks the manufacturer's information.

The CE UV400 and CE 100% UV filter markings have also become established, which correspond to the international standard as well as the medical guidelines.