Glasses Suitable for the Desired Viewing Distance Help Reduce Eye Strain
Significant eye strain can be reduced by using glasses designed for the desired viewing distance (viewing range).
The closest distance at which objects can be seen clearly while the eye is under accommodative effort is called the near point. The farthest distance at which objects can be seen clearly while the eye is relaxed without accommodation is called the far point.
The distance visible from the near point to the far point is called the visual range. Your eyes start to decline with age as early as in your teens, and the near point distance gradually lengthens.
This means that as you age from 10 to 20 and then 30 years old, looking at nearby objects puts more strain on your eyes.
Eye strain can be minimized if you view nearby objects using glasses with accommodative support that helps relax your eyes or glasses that do not require accommodation.
Glasses Not Suitable for the Desired Viewing Distance
Your eyes become strained if you look at nearby objects for extended periods while your natural vision or your glasses/contact lenses are adjusted for distance vision.
This happens because your eyes remain strained even though the optical power is not appropriate for the desired viewing distance.
Many people cause eye strain when looking at close objects through distance-correcting glasses for long periods during work or study.
You may recall many situations such as studying at home, preparing for exams, desk work, smartphone use, working on video display terminals (VDTs), and manual tasks.