Normally, we blink about 15-20 times a minute. 

That spreads tears evenly over your eyes, which keeps them from getting dry and irritated. 

But researchers have found that people blink less than half as often when they’re reading, watching, or playing on a screen. 

Also, the contrast of text against the background, the glare, and flickering from digital screens can be hard on your eyes.

• Make sure your computer screen is about 25 inches, or an arm's length, away from your face. The center of the screen should be about 10-15 degrees below eye level.
• Cut glare by using a matte screen filter. You can find them for all types of computers, phones, and tablets.
• Follow the 20-20-20 rule: every 20 minutes, look at an object at least 20 feet away for at least 20 seconds.
• Take a longer break of about 15 minutes after every 2 hours you spend on your devices.
• Make sure the lighting in the room you’re in is bright enough. You don’t want your device to be brighter than the surroundings.