The Solar Eclipse and Eye Protection
As the Solar Eclipse approaches on August 21, 2017, it is important to be aware of eye safety. Directly viewing the sun can cause permanent damage to the eye. There are two type of damage that occur from direct sun exposure to the eye:
- Photokeratitis - a temporary sunburn of the cornea/front of the eye
- Solar retinopathy - long term and potentially serious damage to the retina (back of the eye)
Looking at the eclipse or sun directly is analogous to the classic childhood experiment of burning dried leaves with a magnifying glass, but with one slight caveat. The focusing and refractive powers of the eye are nearly 4x that of a standard magnifying glass. This means that retinal damage can happen very rapidly when looking at the sun.
After giving out over 500 pairs of ISO certified solar eclipse viewing glasses, our office has run out and we unfortunately have not been able to order more.
There are Four Safe Ways to view the solar eclipse:
- Solar Eclipse Glasses – ISO 12312-2 certified
- Welding shield – Protective Shade 14
- Pinhole Projector Viewer (https://eclipse2017.nasa.gov/how-make-pinhole-projector-vie…)
- Indirect viewing via photos/video
Due to the rarity of a solar eclipse and relatively few manufacturers of solar eclipse viewing glasses, we have reached a classic supply and demand problem with solar eclipse glasses -- high demand and very low supply. Many individuals have taken advantage of this situation by creating and selling fake solar eclipse glasses that may seriously damage the eyes if used to view the eclipse.
Remember to protect your eyes while viewing the solar eclipse, and if you do purchase solar eclipse glasses or use a welding shield, make sure they are up to the proper standards listed above!
And one quick note about viewing the solar eclipse. When participating in direct viewing with solar eclipse glasses, make sure to limit your viewing time to 2-3 minutes, solar eclipse glasses are not made for long exposure viewing.
With that being said, enjoy this very rare moment in Earth's history, and if your eyes somehow do not feel right after the day of the eclipse, you know who to call!
-Dr. Aaron Neufeld
Dr. Aaron Neufeld is the Chief Optometrist at Los Altos Optometric Group and primary author and editor of The EYE Digest.
Contact him with questions or ideas for future articles at (650) 948-3700 or firstname.lastname@example.org