People usually have some knowledge of the harm that continuous and frequent exposure to the sun may have on the skin, but they don’t invariably consider the effects on the eyes. Light is made up of invisible wavelengths that may also cause eventual problems for your eyes. These waves can be divided into visible, and high energy visible (HEV) light that induce ultra violet (UV) damage if you don’t protect your eyes adequately.
While visible light is the part that provides the perception of colour on the eye, HEV is the upper end of the spectrum in the violet blue band approaching ultraviolet. Substantial experience of ultraviolet waves can have effects later in life and can lead to macular degeneration.
Ultraviolet light waves are electromagnetic radiation that is seen to be stronger in higher altitudes or in open highly reflective conditions like water, snow and sand. Ultraviolet waves can be split into three forms of light, UVA, UVB and UVC. While most know that excessive exposure to ultraviolet waves leads to sunburn, there are other damaging effects to health which could occur, particularly on the eyes.
UVA (often known as longwave or black light) penetrates the skin and eyes and could cause untimely aging. It has also been linked to short term eyestrain and fatigue.
UVB (also referred to as medium wave light) is easily the most damaging of the sun’s rays and is known to be one factor in retinal damage and the advancement of cataracts. Ultraviolet B waves are also associated with other issues that can bring about eye disease and possibly blindness.
Ultraviolet waves of the C subtype (often called shortwave or germicidal light) are not a specific problem to the eyes, because they are mostly absorbed by the outer atmosphere before reaching the planet earth. UVC radiation is usually seen in artificial sources such as germicidal light and mercury arc lamps.
Don’t forget when buying sunglasses to look for those with 99-100% protection against UV damage.
It’s not all bad news, of course some exposure is certainly advantageous to your health. The only thing that people should understand is that for health purposes, moderation is highly recommended if you are in direct sunlight.