we have two eyes, our brain manages to see just
one image. This normal viewing process can be
disturbed by excess use- especially when looking
at a close working distance for extended periods
of time. When we lose our ability to maintain
the lock between the eyes, they can
mis-align and aim at different points in space.
If both eyes keep transmitting the image back
to the brain, we will experience double vision,
or diplopia (dih-PLO-pee-ah).
Double vision is a very uncomfortable and unacceptable
condition for our visual system. We will most
likely suppress or turn off the image
of one eye rather than experience the double images.
When viewing a near point object, the eye muscles
converge the eyes inward toward the
nose. Convergence allows the eyes to maintain
the alignment of the image on the same place on
Often times you will not experience this doubling
of vision while using the computer but afterward.
This is a sign that the convergence system is
working, but unable to stop working! Fortunately,
this problem is not common mainly due to the visual
systems survival instinct and
suppression ability. However, it is unfortunate
as well because the symptom of this type of stress
may not be noticeable until it reaches an advanced
stage. This is further evidence for the need for
periodic eye examinations which can determine
your visual abilities for using a computer efficiently.