why they are harmful for the eyes

What are UV-rays?

Apart from causing skin damage, which most of us have probably already experienced or at least heard of in the form of a sunburn, UV rays can cause damage to our eyes as well. But what exactly are UV rays and how can you make sure to protect your eyes against the damage caused by them?

What are UV-rays?

UV rays are ultraviolet light rays that are invisible to the human eye. They are a form of electromagnetic radiation with a wavelength of 10 - 400 nanometers. Their wavelength is shorter than the visible light spectrum, which is why human eyes cannot see them. 

UV rays are emitted by the sun and are part of sunlight. In total UV rays are about 10% of the electromagnetic radiation that the sun puts out. UV rays can be divided into long-wavelength and short-length UV Radiation. 

The sun emits a lot of UV radiation. However, we are only able to inhabit the earth, as we have an atmosphere that protects us from the sun rays by filtering out most of the sun's (harmful) light.

What are the effects of UV-rays for humans?

You can experience this UV radiation exposure most prominently when you get a suntan or sunburn. But UV rays exposure can also increase risks for getting skin cancer. Apart from affecting our skin, UV radiation can have harmful effects on our eyes too and can affect our circadian rhythm and our immune system as well. 

While UV rays have both harmful and beneficial effects, we need to make sure to always protect ourselves accordingly nonetheless. 

The best way to know whether you need to protect yourself and how, is by consulting the UV-index and knowing when and which protection is necessary.

Men     Women

Why are UV-rays harmful for the eyes?

UV rays are harmful for the eyes in particular because UV-ray-exposure can cause eye irritation, decreased eyesight, and can also, in very severe cases, lead to cancer of the eyelid. If our eyes are exposed too much to UV rays, the radiation can affect the eye’s dioptric system, which can be acute or chronic, and also affect our eyes retina.

Further, UV ray exposure can cause conjunctivitis and lead to clouding of the cornea, or even cause a cataract.

How can I protect my eyes from UV-radiation?

When you are out in the sun for extended periods of time, you make sure to apply sufficient sunscreen and/or wear protective clothing to shield your skin from excessive UV-exposure that could lead to harm and damage to our skin. 

Why not do the same to your eyes? The easiest and most affordable way to protect our eyes from UV rays are sunglasses with or without strength.

Common sunglass protection indicators

Sunglasses can be classified in different UV-factors, similarly to the SPF in sunscreen. The most common is UV400.

Lenses can be categorised into 5 different categories, which indicate the tint and darkness of the lense like this:

Category 0: 3-20 %

Category 1: 20-57 %

Category 2: 57-82 %

Category 3: 82-92 %

Category 4: 92-97%

Sunglasses that have the indicator ‘CE’ should filter at least up to wavelengths of 380 nanometers and are in accordance with EU-guidelines. Further, it is important that the sunglasses you buy to protect your eyes cover your whole eye. 

Luxreaders sunglasses are UV400 and have category 3.

What is UV400?

If your new sunglasses have an indication of UV400, that means that the glasses will filter radiation and light up to a wavelength of 400 nanometers. This is why UV400 is also called “100 percent protection” as it protects your eyes from the full spectrum of wavelengths of UV radiation (which is up to 400 nm).