What is eye strain?
The term eye strain is frequently used by people to describe a group of vague symptoms that are related to use of the eyes. Eye strain is a symptom, not an eye disease. Eye strain occurs when your eyes get tired from intense use, such as driving a car
for extended periods, reading, or working at the computer. If you have any eye discomfort caused by looking at something for a long time, you can call it eye strain.
What causes eye strain?
The medical term for eye strain is asthenopia. The symptoms of ocular fatigue, tired eyes, blurring, headaches,
and occasionally doubling of the vision are brought on by concentrated use of the eyes for visual tasks. Some people, while concentrating on a visually intense task such as reading fine print, using the computer for hours at a time, or trying to see in the dark, unconsciously clench the muscles of their eyelids, face, temples, and jaws and develop discomfort or pain from overuse of those muscles. This may lead to a vicious cycle of tensing those muscles further and causing more distress. Other people attempting to do similar visual tasks may have no symptoms at all.