Do You Really Need Special Glasses to Watch a Solar Eclipse?

solar eclipse
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Many people may not realize it, but the only safe way to view a solar eclipse is through special solar filters. Your eyes and vision are one of your most precious senses. It may not seem possible, but damaging your eyes by simply looking up at a solar eclipse is extremely likely. Wearing special “eclipse glasses” is strongly recommended for viewing a solar eclipse. The American Optometric Association (AOA) suggests using a handheld solar viewer, special-purpose solar filters, or other ISO-certified filters if you plan to view a solar eclipse for even a short period of time.

Risk to Your Eyes

It may seem harmless, but looking at a solar eclipse with naked eyes can cause serious eye injury and even permanent damage to your eyes. Excessive amounts of ultraviolet radiation can cause photokeratitis, which is much like a sunburn to the eyes. Looking directly at the sun during an eclipse can also cause solar retinopathy.

On a normal sunny day, looking directly at the sun causes pain, forcing you to look away before damage is done to your eyes. However, during a solar eclipse, the sun appears less bright, allowing you to stare longer. You won’t realize it, but as you are staring at the eclipse, the ultraviolet rays are burning cells off of your retina. Once the retina is burned, there is no way to repair the damage and vision will be lost. The rays are strong enough to cause partial or permanent blindness.

Why You Need Special Glasses

If you want to view a solar eclipse, you must wear special eclipse glasses.

 Filters for viewing are sold in the form of wearable “eclipse glasses” or "eclipse shades" or as solar viewing cards that you hold in your hand. These simple devices reduce sunlight to safe levels to avoid injuring your eyes. The AOA encourages ordering solar eclipse glasses that conform to the American Astronomical Society’s (AAS) standards.

A list of certified manufacturers can be found on the AAS website. Before a major solar eclipse, the marketplace becomes flooded by counterfeit eclipse glasses that are labeled as if they're ISO-compliant when in fact they are not. Ordinary sunglasses are not safe for viewing a solar eclipse.

What to Look For

You may have found a cheap pair of solar glasses online. Unfortunately, simply seeing the ISO logo on a viewing device does not mean the product is completely safe. The device must come from a reputable manufacturer or an authorized dealer. Check the AAS website for a list of safe vendors.

Also, check the device for safety yourself. Look through the glasses and make sure you can’t see lights of ordinary brightness. You should only be able to see extremely bright light, such as the sun or a bright-white LED flashlight. These lights should all appear quite dim through your device. If the normal sun appears uncomfortably bright, the device is probably no good and is non-compliant with ISO standards. In addition, make sure your device is free of scratches or holes.

Tips for Viewing a Solar Eclipse

If you plan on viewing a solar eclipse, have your ISO-compliant special eclipse glasses ready and follow these important safety tips:

  • If you wear eyeglasses, put your eclipse glasses on over them. If they do't fit, hold a handheld viewer in front of your glasses.
  • Supervise young children using solar filters.
  • Cover your eyes with your eclipse glasses before looking up at the sun. Also, do not remove your glasses while looking at the sun. Look away first, then remove them.
  • Do not stare continuously at the sun, even through special glasses. Take frequent breaks by looking away.
  • Enjoy the rarity of solar eclipses safely by following safety procedures.

A Word From Verywell

If you look directly at the sun during a solar eclipse and think you may have damaged your eyes, it is best to see an optometrist immediately.

It is extremely important to ensure that no serious or permanent damage has occurred, even though you have no signs or symptoms of damage. It is always better to be safe than sorry when it comes to your vision.

Sources:

Behar-Cohen F, Baillet G, Ayguavives, T, et al. Ultraviolet damage to the eye revisited. Clin Ophthalmol. 2014; 8: 87–104.​

NASA Recommends Safety Tips to View the August Solar Eclipse, NASA. August 2017.

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