It’s only been a few weeks back to school and your child is already squinting at the computer screen trying to do their homework. Or maybe they aren’t sleeping as well as they did this summer.

Blue light could be the culprit.

With the return of school comes homework, after-school video games, and lots of computer and phone blue screen time. A Harvard University study has shown that a pair of glasses with blue light lenses might be your best investment in your child’s learning.  

“Kids are doing a lot more on-screen work because of COVID-19 and are being exposed to more blue light and that puts a demand on their focusing system,” said Dr. Joseph Hammond, an optometrist with VisionFirst Eye Care in Louisville. “Studies have shown that blue light can cause eye strain and, over time, potential structural degradation to the eye.”

Blue light can change a child’s quality of sleep. Harvard researchers conducted an experiment comparing the effects of 6.5 hours of exposure to blue light to exposure to green light of comparable brightness. The blue light suppressed melatonin for about twice as long as the green light and shifted circadian rhythms by twice as much (3 hours vs. 1.5 hours).

“So, if your child is working on the computer or tablet an hour before bedtime, that exposure to blue light can actually decrease their melatonin levels in the brain and cause a decreased amount of sleep,” said Dr. Hammond. “The next day, the tired child ends up with an inability to function.”

To reduce the amount of blue light exposure, Hammond recommends incorporating blue light filters into their glasses. “Eyezen glasses filter up to 20% of harmful blue light rays by letting beneficial blue-turquoise light pass through and deflect blue-violet light,” he explains.

Blue light lenses are built into the eyeglasses, so your child does not need an extra pair of glasses or need to switch glasses when they are done with screen time. Kentucky law requires that any child entering public school for the first time between the ages of 3 and 6 have an eye exam, which could be a good time to discuss blue lenses. Annual eye exams before the start of school ensures your child is not struggling with reading due to a vision problem.

“When a child is eight or nine, the eyes are making their most important connections. That’s the timeframe we need to also catch certain vision disorders, strengthen the eyes and get them to see their best,” said Hammond. “If the eyes aren’t working together, you're going to have issues with depth perception, judging distances, reading and eye strain. We conduct different vision tests so we can diagnose vision disorders that may affect their ability to learn and have plenty of visual corrective lenses to address these problems.”

Getting your child on the right path to a successful school year is more than just having the right notebook or the coolest backpack. “Sometimes just giving your child a pair of glasses allows them to learn and engage educationally to their fullest,” said Dr. Hammond.

For more information on Eyezen or to make your child’s annual eye exam appointment, contact Dr. Joseph Hammond at VisionFirst Eye Care, 2110 S Hurstbourne Pkwy Louisville, KY 40220; (502) 491-2232 or 4000 Poplar Level Road, Louisville, KY 40213; (502) 459-2020 or visit