 Your
Eyes and Your Computer
Vision Care Solutions For Computer Users
by
Robert Elsas, Vice President, Business Development
Davis Vision
Close your eyes for a moment and visualize your business operating
without computers. It is hard to imagine, isn't it? Unquestionably,
computers have become an ever-present tool in our offices and, as
the Internet grows, we'll be spending more and more time staring
at our computer screens way beyond office hours. It is estimated
that by the turn of the century 75% of all office workers will have
a computer and video display terminal (VDT) on their desks, equating
to nearly 100 million users, with many millions regularly using
another computer at home.
While mass computer expansion at home and in the office offers
a big boost to global communications, computers have and will continue
to take a toll on our eyesight. The National Institute for Occupational
Safety and Health has reported that eyestrain is prevalent in nearly
90% of all computer users and occupational health experts agree
that today's number one source of vision complaints in the workplace
is the computer monitor. "Eye strain is a common problem for adults
who spend four hours or more each day concentrating on a computer
screen," says Dr. Kent Daum, an optometrist at the University of
Alabama School of Optometry. "And even short 25-minute periods can
cause some eye discomfort." In addition to eyestrain, many computer
users complain of tired, burning, itching, dry and/or watery eyes,
headaches, double vision and afterimages, photophobia (sensitivity
to light), pain in the eyes, or excessive blinking or squinting
resulting from work at the terminal. James Sheedy, O.D., Ph.D. coined
the phrase "Computer Vision Syndrome" (CVS) in reference to these
myriad ailments.
Computer Vision Syndrome -- together with transient visual complaints
(asthenopia) among VDT workers -- resulted in more than 15 million
workers seeking eyecare treatment for computer-related vision problems
in 1995. According to Stewart B. Leavitt, Ph.D., in his report "Vision
Comfort at VDTs," the costs for this medical treatment and lost
productivity associated with vision-related disorders among VDT
users could amount to several billion dollars annually.
VDT Issues
Jesse Rosenthal, O.D., MPH, and Mort Soroka, Ph.D., in their highly
acclaimed book, Managed
Vision Benefits, cite the following critical areas of concern
that are characteristic of interfacing with computer/video display
terminals.
Illumination
This relates to the work environment. Unlike other office equipment,
VDT screens are self-illuminating and made of glass. Therefore,
there is the potential for flickering or unclear characters as well
as reflection from surrounding light sources. Poor contrast, poor
resolution, glare and reflections on the screen can exacerbate CVS
symptoms.
Visual Intensity
This refers to the level of intensity required for many computer
tasks, particularly data entry, information retrieval or programming.
These jobs require continuous, uninterrupted activity at a computer
station. Under these conditions, the eye's focusing mechanism is
more vulnerable to fatigue and the proper eyeglass prescription
is essential.
Interaction and focal distance between user and computer screen.
We conventionally hold reading materials 12 to 18 inches from our
eyes, and eye doctors typically prescribe reading or "near vision"
prescriptions for that range; however, computer stations are usually
situated with the VDT screen 20 to 26 inches from the user. Therefore,
many people require a special lens prescription that will help them
focus clearly at these distances for extended periods.
VDT screen heights for wearers of bifocals and trifocals. In these
corrections, the prescription for close tasks is set into the lower
portion of the lens. While reading, we generally hold written materials
so that we lower our eyes and automatically look through the bifocal
or trifocal for clear focus. VDTs, on the other hand, are set relatively
high, at or near eye level. As a result, wearers of bifocals and
trifocals may require special lenses to function effectively and
efficiently at computers.
VDT Solutions
Employees who work for extended periods of time at a computer and
believe that they are in need of corrective lenses for their VDT
work should have a comprehensive eye examination. Some employers
have set a prescribed period of work time at a terminal as their
qualification for VDT vision coverage. If there is a standard vision
care employee benefit, the special testing can be performed in conjunction
with the dress benefit eye examination. This ensures convenience
to the employee, while providing maximum cost-effectiveness by avoiding
duplication of services.
Drs. Rosenthal and Soroka emphatically agree that computer users'
eyesight requires additional testing. It has been shown that "task
specific" glasses can decrease visual complaints. Eyeglasses that
are specifically suited for working with the computer display must
differ significantly from the employee's dress eyewear. Rosenthal
and Soroka suggest the following guidelines for occupational eyeglasses
and spectacle prescriptions:
Rx difference of at least .50 diopter;
Different lens type, e.g., single vision versus bifocal;
Seg height difference of at least 5mm; for workers over 40, it
is important that the height of their bifocal segment match the
screen height.
10%-20% tint in gray or pink
In addition to the eyecare solutions set forth here by Rosenthal
and Soroka, the following suggestions may be of value:
- The greater the hertz or frequency of the monitor's screen,
the less perceptible will be the flicker in the screen. In addition,
the higher the pixel (dot) count of the monitor's screen, the
better the resolution, resulting in enhanced readability. Resolutions
of at least 110 dots per inch are recommended.
- Glare from lights reflecting off the screen will lower the contrast,
thus forcing the eyes to work harder. A glare-reduction filter
can lessen this potential problem significantly. It is recommended
that your filter have the American Optometric Association seal
of approval.
- Adjustable work stations allowing for appropriate placement
of the computer screen at an angle of 10-20 degrees has been found
to be the most comfortable.
- Ergonomically designed chairs and keyboards and proper ambient
illumination all can provide additional relief.
Time and again, VDT vision plan benefits are proving mutually beneficial
for both employers and employees. These programs have helped employees
see more clearly, relieve eyestrain and fatigue, avoid headaches,
and work more accurately and efficiently. In a study of employees
of the State of New York where a VDT vision program was implemented,
94% revealed improved comfort and resolution of their symptoms,
and 82% reported improved quality or efficiency of work with the
use of their occupational eyeglasses.
Studies continually show us that it is in the financial interest
of the employer to assist in the provision of these services. It
is not a costly benefit, and it adds directly to the bottom line
by bringing greater comfort and increased productivity to employees.
"Nothing
on this web site is intended, nor should it be construed, as professional advice.
Those reviewing the information should consult with a qualified professional."
|
