| At both home and the office, patients are spending an increasing
portion of their day using computers. Many patients complain of eyestrain,
headaches, dry eyes, contact lens intolerance, frequent blinking and other
computer related ocular complaints. To minimize these adverse effects our
doctors can analyze a patient's individual computer demands and work station
ergonomics to arrive at an optimum computer prescription or other vision
related recommendation for computer use. Our doctors recommendations may
be the key to making computer related work less stressful, more comfortable
and more productive.
Computers are not
damaging to the eyes and visual system, however, they do create the following
visual demands that are unlike most demands the human visual system is familiar
with:
- Most conventional reading
activities are performed at about a 16" reading distance. Computer monitors,
however, are often placed at a 20-26" distance. The intermediate computer
monitor distance requires an entirely different prescription than a conventional
reading prescription.
- Most conventional near demands
are in down gaze such as while reading a book or doing desk work. Computer
demands involve near tasks in down gaze (the keyboard or reference text),
as well as the unique computer related intermediate demands in a straight
ahead gaze ( the computer monitor). Most bifocals only provide near prescriptions
in down gaze.
- Progressive "no line" bifocals
and trifocals do provide an intermediate prescription portion, however, the
intermediate lens area is too small for prolonged computer work. An individualized
computer prescription may be prescribed that provides a much larger field
of view than most bifocal or trifocal designs.
- Computer monitors can create
uncomfortable glare and contrast conditions. Reflection free and other ophthalmic
coatings can eliminate 99% of disturbing glare and reflections, while increasing
computer monitor visual contrast.
- Proper visual hygiene can
further improve visual comfort and performance by taking a short break (15
minutes) every two hours.
- Computer workstations should
be set up a way so as to avoid glare and reflections from windows and other
sources of illumination.
- Computer contrast demands
coupled with computer flicker often lead patients to stare at the computer
monitor and result in a decreased blink frequency. Eventually the decrease
in blink rate leads to a dehydration of the tear layer resulting in red,
dry, burning eyes. Frequent voluntary blinking can reduce these effects.
When necessary, artificial tears can be prescribed to alleviate symptoms.
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