AOL File Library: 2,801 to 2,900/aol-file-protocol-4400-2801-to-2900.zip/AOLDLs/TAWUG/TAWUG Disk No. 47 (SHK)/TAWUG47.shk/COMPUTERSANDVIS

AppleWorks Document | 1987-02-01 | 9KB | 150 lines

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COMPUTERS AND VISION
by Dr. Sam Baron
>Ergonomics is the science that seeks to adapt work or working B
@conditions to suit the worker.  The following is some ergonomic G
Einformation regarding vision and computers.  More people are working H
Fwith computers than ever before; statistics show that the number will E
Cincrease greatly over the next five to ten years.  Because of this G
Etrend toward greater computer usage and the resulting demands on the I
Goperator's vision, we have completed a study of the current literature F
concerning this type of work, which we would like to share with you.
AThe chief physical complaint of people working with computers is H
Fvisual strain and fatigue.  Studies show that 47% of computer workers E
Chave eye strain, within three hours of initiating their work.  One I
Gcause of discomfort and inefficiency is
GLARE
.  Glare may be defined I
Gas "something in the line of sight that is significantly brighter than E
Cthe surroundings." The computer display screen acts like a mirror, E
Creflecting light or bright colors.  It is, therefore, wise to have I
Gcurtains over windows, and dark, or flat (matte) painted walls.  Also, B
@the operator should refrain from wearing white or light colored =
;clothing.  Other means of reducing glare are: utilizing an C
Aanti-reflective screen on the monitor; changing the angle of the B
@screen by tilting it horizontally or vertically; or moving your H
Fstation to a different position.  If your desk is of a shiny laminate H
Fmaterial, use a matte-finished desk blotter to degrade the reflective F
Dquality.  A good test to determine whether glare is a problem is to G
Eplace a 12" X 12" mirror over the screen, keyboard and desk.  Sit in I
Gyour normal position; if you see any of the light or bright sources in I
Gthe mirror, you are actually demonstrating glare.  If this occurs, try
to eliminate or reduce it.
=Proper
LIGHTING
 in the office is very important.  Prior to G
Ecomputers, it was recommended that a general office have about 1,000 E
Clux of light.  With the use of computers, however, that figure was F
Dreduced to 300-500 lux.  The prime reason for this reduction in the G
Eamount of light is that a sharp contrast between the monitor and the G
Ebackground is a major source of visual discomfort.  Older people may @
>benefit from task lighting, where copy work is illuminated by
auxiliary lighting.
@Let us consider the
MONITOR
 unit itself.  Make sure that your F
Dcomputer monitor does not have a "ghost" image on the screen, which D
Bindicates a problem with phosphene absorption.  Fortunately, most G
Escientific research papers studied note that OSHA's studies indicate E
Cthat the radiation emitted from the monitor is not harmful, but is G
Ewell within the general environmental background radiation.  Studies E
Calso indicate that a black-and-white screen is better than a color C
Amonitor because it has a refresher rate of 60 cycles per second, E
Cwhereas color has a rate of 20 cycles, presenting more distressing
visual flicker.
FAnother source of visual distress is the
FLICKER
 in your peripheral D
Bfield of vision from other monitors.  If that is a factor, try to G
Eshield these from your peripheral field of view.  There should be as H
Fmuch flexibility as possible in the placing of computer components so G
Ethat they can be adjusted to each operator's specific needs.  If the C
Ascreen has a swim to it (movement of the display), it is best to F
Dchange to a better monitor. It is most importing that the images on
the video screen are clear.
GThe average visual
WORKING DISTANCE
 for people using computers is 20 E
Cinches.  If all your material--copy, keyboard, screen-- are at the C
Asame distance of 20 inches, the fatigue factor will be decreased G
Ebecause there will be less varying focusing demand on your eyes.  It C
Ais also important to take breaks (one, five minutes per hour, is E
Csuggested); this benefits your body and your mind, as well as your E
Ceyes.  Look out a window at a distant object or view, or vary your ?
=task to another office duty for a while.  Visual comfort and H
Fefficiency are interrelated; it is to your employer's benefit to have I
Gyou as visually comfortable as possible.  Computer work demands a very I
Ghigh standard of vision.  Because there is such a great demand on your 4
eyes, there is always the potential of eye strain.
CTypically, in years past, eye care for a person without a specific A
complaint was non-existent.  Today,
PREVENTATIVE HEALTH CARE
INCLUDES VISUAL CARE
, and is becoming more informative in defining I
Gwhat can be done to prevent certain problems.  One study revealed that H
Fthere was temporary reduction in vision after three hours of computer I
Gwork.  The patients in the study went from 20/18 (actually better than G
E20/20) to about 20/25, after three hours at the computer. After they H
Fstopped their work, it took about sixteen minutes to recover to their E
Coriginal 20/18 level.  It is not unusual for computer operators to I
Ghave difficulty in making a visual shift from near to far and from far I
Gto near.  This complaint may be a predecessor of nearsightedness or of F
Dan increasing amount of nearsightedness, or presbyopia, a condition 2
which is improved by the use of reading glasses.
BStudies show that with extensive use of computer monitors, people H
Funder the age of forty tended to
INCREASE IN NEARSIGHTEDNESS
, while H
those over forty tended to
INCREASE IN THE NEED FOR READING GLASSES
AMany times this new environment makes it necessary for operators C
Athirty-five to forty, or older, to get special glasses for near, F
Dusually in bifocal form.  Bifocals are usually in the lower half of C
Athe lens, so that one can read on his desk, lap, etc.  Since the G
Ecomputer monitor is straight ahead, at eye level, it is possible for I
Gthe operator to view the screen through the typical bifocal only if he I
Gtips his head back--a position that quickly becomes tiring and creates E
Ca pain in the neck.  Fortunately, there are ways of resolving this I
Gproblem:
SPECIALLY DESIGNED, SPECIAL-PURPOSE LENSES
 may be used as a A
?peripheral to your computer, a very specific component to your I
Gcomputer, and your link with it through your eyes.  Wider bifocals can E
Cbe designed to fit very high; this would work well at the computer J
Hmonitor, but would not be appropriate for general purposes or walking.  I
GSpecially designed single-vision lense, focused for the computer world F
Dof about 20 inches, give another alternative that works well, as do H
Fvery high-fitting half-eyes.  Occasionally, tints are appropriate, to G
Ecut down glare or flicker.  For the office environment, a light pink
tint is the best choice.
Let us draw a parallel between the
COMPUTER OPERATOR AND A MARATHON
RUNNER.
  The runner must stretch, exercise, and train, in order to @
>perform at his highest physical level.  He must also have the F
Dappropriate shoes for long-distance running.  The computer operator E
Cmust also be well prepared with, in his case, a very high level of B
@visual skills.  The visual skills are the focusing ability, the F
Dability to make the eyes fuse together easily, and eye-tracking and I
Geye movement skills.  Developing these skills would be like the runner H
Fdeveloping his body.  Appropriate glasses for the computer operator's H
Fnear visual needs could be likened to the best possible running shoes H
Ffor the marathon runner, both of which may help prevent problems from
such demanding tasks.
FIt is important that your
EYES BE CHECKED FOR NEAR VISUAL NEEDS
, as A
?well as for distance vision, as these are two different visual I
Gfunctioning situations.  Some studies show that because of a change in I
Gevolution from our being outdoor people to becoming very near-oriented E
Cpeople, nearsightedness has increased from 12% to 70%, in the past I
Geighty years.  The higher the visual demand, the more imperative it is
to have more frequent care.
BThe most common complaints of computer operators, regarding their I
Gvision, include rubbing eyes; headache; blurring of vision at both the I
Gnear and far viewing distances; itching and burning eyes; eye fatigue; F
Dflickering sensations; losing place; increasing errors with reduced E
Cvisual efficiency; double vision.  Most computers have a six month +
service warranty and maintenance program.
WHAT IS THE MAINTENANCE PROGRAM FOR YOUR EYES?