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What is Sun Glare?Sun Glare is when the light from the sun affects our ability to see clearly. There are two types of glare, discomfort glare and disability glare.
What is Discomfort glare?Discomfort glare occurs when sun light is just too strong for our eyes. It may cause us to screw up or shade our eyes, it can even cause us to close our eyes. A good example of discomfort glare is being sat on a beach with bright sun, light sand and the white pages of a good book. Our eyes can adjust by making the pupil smaller, but the intensity of light just feels uncomfortable and sometimes painful. As the name suggests, discomfort glare can make our eyes feel uncomfortable.
What is Disability glare?Disability glare reduces our visual performance. Disability glare can be caused by eye diseases and can occur with ordinary levels of sun light. The structures of the eye are normally clear, which means the light passes directly through our eye. As we age certain eye problems can make the eye’s structures less clear. The most common example of this is a cataract. When someone has a cataract, the lens in their eye is not as clear as it should be. This causes the light entering the eye to scatter. The light does not pass smoothly through the lens and scatters throughout the eye. This effect, as well as making things unclear and blurred, also makes coping with bright light difficult. The amount of scattering of light depends on the amount of light entering the eye and how thick the cataract is. This means that a brighter light will scatter more, causing things to become more blurred and causing more glare. People with cataracts often have a lot of trouble with sun glare. You will often see seniors at the bowling club shading their eyes on a sunny day. This is their way of coping with sun glare when they have cataract developing.
What are the causes of Sun Glare?Some people are born with a lack of pigment in the eye, ocular albinism, and this causes glare. Eye diseases such as cataracts, macular degeneration and uveitis can cause glare. Other eye problems such as conjunctivitis and corneal problems can also cause difficulties with glare. There are some conditions such as meningitis that cause light to be painful.
If you start to experience light sensitivity then it is always best to have it checked out by an optometrist as it may be the first sign of an eye disease which may need treatment. Some drugs taken for other conditions can also cause light sensitivity for example tetracycline, an antibiotic, and digitalis, a drug which is used for heart problems.
How to deal with Sun Glare when readingThe most obvious way to cope with glare is to limit the amount of light that is entering the eye. Some people find wearing a hat with a wide brim can help cut down on glare with little expense.Tinted lenses help to minimise the light entering the eye and so cut down on the amount of glare someone experiences. Sunglasses should have an UV filter so they also protect your eyes from the harmful UV rays of the sun. The best lens will have protection against UVA and UVB light. Some people prefer to have light activated sunglasses, which get darker in brighter conditions, though this is a personal choice.Polarized lenses can cut down on reflected glare from flat surfaces, for example, light reflected off water or off the bonnet of a car. There are sunglasses, sometimes called solar or UV shields or wrap-around shades, which are larger than normal. They have built in sides which stop the light entering that way and they are also made to stop the light entering from above the eyes. They can also be worn over regular spectacles and come in a variety of tints. These can be very helpful but the fit of them is important. Everyone has a different shaped head and several pairs of wrap-around sunglasses should be tried to find the ones which fit closest and stop the most light from coming in around the edge of the frame.
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