|
Eye and vision problems are frequently received complaints
among computer users. Currently there is no evidence that prolonged computer use can cause
permanent eye damage. However, because computer work is visually demanding, people with no
previous eye problems may experience eyestrain and develop a need for glasses.
It also can make the symptoms more noticeable for people with existing eye
problems. The common eye problems associated with computer use are irritation, eye
fatigue, blurriness and headaches. According to the PEOSH VDT guidelines, the computer
user who spends 10 hours or more per week on a regular basis should have initial vision
examinations before or soon after beginning work as a VDT operator.
Below are some of the special computer glasses for use
while working on computers:
Single vision lens
This type of lens is adjusted for the distance from eye to
the monitor screen and documents. It is preferable for those who use the computer for
extended periods of time and rarely do distance work.
Bifocal Lens
This lens has a near focus on the bottom and intermediate
viewing on the top specifically for computer work. They can be used for those whose near
range vision is narrow and need little distance viewing.
Trifocal lens
It has a near focus on the bottom and an intermediate focus
in the middle for monitoring view and distance focusing on the upper portion. These lens
are good for people who perform tasks that require near and distance viewing.
Task-specific progressive addition lenses
Unlike the lenses described above, additional lens power is
added gradually for near, intermediate and distance viewing. It is claimed that this lens
minimizes blurring that can occur in the single, special bifocal and trifocal computer
lenses.
If you wear corrective lens, the easiest way to avoid the
change of visual fields is adjust the computer monitor until your correction works
comfortably. For people who wear bifocal lenses, it is preferable to place the computer at
a low position to avoid the need of tilting the head backward to see the monitor.
|
