Staring at the sun during solar eclipse can cause permanent damage, local doctor warns

The London, Ont., region is in the path of a solar eclipse on Monday, an astronomical event that is sure to draw the attention of thousands of curious eyes.

But staring at the sun, even when it's just a sliver in the sky, can do serious harm, so a London eye doctor is warning to make sure everyone takes the proper safety precautions.

"Basically, what's happening is the sun is being focused on a very small part of the film in the back of the eye. The retina and the amount of energy being supplied to that area is far more than can be tolerated and the cells are damaged, and so you end up with a permanent area in the very centre of your vision that doesn't work properly," said Dr. Phil Hooper, an ophthalmologist at the Ivey Eye Institute at St. Joseph's Hospital and president of the Canadian Ophthalmological Society.

The eclipse is expected to last about two hours, with complete darkness ocurring for three minutes at 3:17 p.m. when the moon crosses in front of the sun, blocking it out.

To avoid eye damage and vision loss, Hooper recommends wearing solar-viewing glasses that comply with ISO 12312-2 international standards and make sure those glasses are not scratched or damaged in any way. Do not look at the sun through an optical lens while wearing eclipse glasses as they can concentrate solar rays.

"The only difficulty with the eclipse glasses is that they are totally black unless you're looking directly at the sun, and so it's difficult to move around with them. People need to get in position, not look at the sun, put them on when they're looking away and then look up toward the sun. So there are a lot of steps there in which things can go wrong," said Hooper.

Another way to avoid eye damage and vision loss is to use indirect viewing.

"With the sun behind you, you make a pinhole camera effect, projecting the image onto a sidewalk, a building or even a sheet of paper and allowing you to look at it indirectly," said Hooper.

Symptoms of solar retinopathy can include blurry vision, vision loss in the centre of your sight and eye pain.

"Unfortunately, when this damage happens, there isn't very much we as physicians can do to change the course of the healing. It will either heal on its own or not, but there's very little that we can do to alter the course."

Hooper said people who experience symptoms after watching the eclipse should see an eye-care professional as soon as possible.