Below are common symptoms associated with each eye problem.
Nearsightedness: Blurred vision that's worse when you are looking at distant objects suggests that you may be nearsighted, or myopic. People with myopia often have very good near vision.
Farsightedness: Blurred vision that's present when you are looking at near objects or, more commonly, near and far objects indicates that you may be farsighted, or hyperopic.
Astigmatism: Blurry vision can occur at any distance...
Dim light might make it difficult for the eyes to focus, which can cause short-term eye fatigue, says Richard Gans, MD, FACS, an ophthalmologist with the Cleveland Clinic Cole Eye Institute. "But there is no scientific evidence that reading in the dark does any long-term harm to your eyes," Gans says.
Challenging visual work, such as reading in insufficient light, can also lead to short-term drying of eyes because you blink less often, Gans adds. Again, this is uncomfortable, but it doesn’t damage the structure or function of the eyes. You can use over-the-counter lubricating drops if dry eyes are a problem.
On the off chance that your next question is going to be, "What about sitting too close to the TV?" we have the same answer. Getting too close to the set for your favorite shows won’t harm your eyes -- "either from overfocusing or from radiation," Gans says.