Optometrists say parents need to be careful how much time children are spending on screens during lockdown.
There is a risk of developing myopia, or short-sightedness, according to the College of Optometrists.
They said spending at least two hours outside was beneficial to children’s eyesight, and advise regular breaks from screens for all ages.
“If you can keep that time down, it’s beneficial to your eyes,” Llandudno optician Rhodri Williams said.
“There’s less of a risk of children developing short-sightedness if they spend a lot of time outside.”
“If you get the chance to watch a film and you could either watch it on your phone or a TV screen on the opposite side of the room, always choose the TV,” he said.
“The reason is, if you’re focusing closely for a long time it can be tiring for your eyes.
“Also, if you’re young, under about 15, if you’re looking at close things for a long time, it could mean you develop short-sightedness.”
“If you are a child, between six and 13, and you’re doing all your homework on screens, and using it for social reasons too, then it is important you also take a couple of hours a day looking at things far away,” said Daniel Hardiman-McCartney, clinical adviser at the College of Optometrists.
There is also a concern four and five-year-olds could miss out on essential sight checks at school unless the process restarts soon.
“If you miss that opportunity when they’re four or five, there is a possibility they could grow up with eye weakness for the rest of their lives,” Mr Williams said.
“But at the moment, the screening isn’t happening at schools. If children won’t be going to school for the next six months, someone needs to come up with a plan to make sure this screening happens. We have to make sure we don’t fail these children.”
The College of Optometrists has advice for adults concerned about the effect of using more tech on their eyes during the lockdown.
“If you’re using a screen, use the biggest one you have,” said Mr Hardiman-McCartney.
“Don’t read it above you if you’re lying down, and avoid reading on your side. Both practices are likely to cause eye strain.
“If you’re in your 30s and 40s especially, crank up the font size, making it larger.
“Every 20 minutes, try and have a break. We have a 20-20-20 rule. Pause, look 20ft away for 20 seconds. Let your eye muscle relax, squeeze stagnant tears away.
“Also, use your glasses. Don’t cheat. If an optometrist has advised you should wear glasses, it makes sense to use them.”