Darnell Deans' computer and Blackberry are essential in his work for a community group.
"I can spend a good 10 to 12 hours communicating all day," Deans said.
But earlier this year, Darnell noticed he was feeling more drained, earlier in the day.
"I was having problems focusing on my computer. Sometimes it would get real blurry and then I started getting headaches," he said.
During an exam with optometrist Dr. Tamara Hill-Bennett, Darnell learned he had computer vision syndrome.
The symptoms include dry or irritated eyes, eye strain, fatigue, and headaches.
"They're not blinking enough, and they're not getting enough moisture to the eye, or too much overhead lighting," Dr. Hill-Bennett said.
A recent survey by optometrists shows that nearly a third of patients have some symptoms.
Dr. Bennett says computer vision syndrome doesn't cause permanent damage, but it does decrease productivity.
She says the fixes are fairly simple - glasses with a special coating can help with focusing.
"Turn off the fluorescent light, and put a desk lamp onto the desk, and keep some of that glare off the computer," Dr. Bennett said.
But most importantly, follow the 20-20-20 screen rule to give your eyes a break.
"Every 20 minutes that you're on the computer, take 20 seconds to look 20 feet away," Dr. Bennett said. Darnell says these tips are helping to relieve his eye fatigue.
"It's been working so far, I'm doing a lot better," Deans said.