Can staring at a computer screen for long periods of time damage eyesight?

No: Computer monitors pose no danger to the eyes.

Too much LED: Watching too much led light is not going to make you go blind. However, it can cause your eye muscles to get tired, just as if you exercised for hours and your leg muscles got tired. That is eye fatigue. However, recent studies do show excessive looking at led light can decrease melatonin levels in your body, which can adversely affect your sleep and cause insomnia and poor sleep.