Kate Fotheringham
2003-11-26 17:56:56 UTC
Assignment #7
Article Summary
Ankrum, D. (1996). Viewing distance at computer workstations. Retrieved
November 20th, 2003, from http://www.office-ergo.com/viewing.htm
How far away should you sit from your computer screen? The
recommendations that exist for this have no scientific basis. When eyes
are looking at close objects (i.e., the computer screen) they do two
things: accommodate and converge. Unfortunately both accommodating and
converging contribute to eyestrain. Accommodation is when the lens
capsule in your eye changes shape to focus on a close object and
convergence is when the eyes turn inward toward the nose when we view
close objects. Eyes also have a resting position of vergence which
distance at which the eyes are set to converge when there is no object
to converge on. From experiments performed it has been concluded that
"the stress on the convergence system may be the crucial factor for
visual strain". If the viewing distance is the factor to consider
sitting farther away from the computer is better. The distance to sit
away from the computer should not be less than the resting point of
vergence. If you sit closer than that you will definitely experience
discomfort. Your discomfort will depend on how long you've been working
at the computer, your individual visual system's capabilities, and a
number of other factors. There is no limit on how far away you should
sit from your computer because so far there is no evidence supporting
the theory that sitting farther away from the computer causes visual
strain. In order for this problem to be solved we need to allow for
greater eye-to-screen distances, software and monitors that helps make
fonts larger and we need to get rid of guidelines that force people to
work to close to their monitor.
Article Summary
Ankrum, D. (1996). Viewing distance at computer workstations. Retrieved
November 20th, 2003, from http://www.office-ergo.com/viewing.htm
How far away should you sit from your computer screen? The
recommendations that exist for this have no scientific basis. When eyes
are looking at close objects (i.e., the computer screen) they do two
things: accommodate and converge. Unfortunately both accommodating and
converging contribute to eyestrain. Accommodation is when the lens
capsule in your eye changes shape to focus on a close object and
convergence is when the eyes turn inward toward the nose when we view
close objects. Eyes also have a resting position of vergence which
distance at which the eyes are set to converge when there is no object
to converge on. From experiments performed it has been concluded that
"the stress on the convergence system may be the crucial factor for
visual strain". If the viewing distance is the factor to consider
sitting farther away from the computer is better. The distance to sit
away from the computer should not be less than the resting point of
vergence. If you sit closer than that you will definitely experience
discomfort. Your discomfort will depend on how long you've been working
at the computer, your individual visual system's capabilities, and a
number of other factors. There is no limit on how far away you should
sit from your computer because so far there is no evidence supporting
the theory that sitting farther away from the computer causes visual
strain. In order for this problem to be solved we need to allow for
greater eye-to-screen distances, software and monitors that helps make
fonts larger and we need to get rid of guidelines that force people to
work to close to their monitor.