Eyestrain may result from a need for eyeglasses or from use
of out- grown glasses. It may also result from unfavorable conditions under
which the eyes arc used.
Improper lighting,
especially for reading or close work, frequent cause of strain
Do not face the
light; it should comefrom theback of you and from the side so you are not in
shadow, make sure light bulbs are strong enough (75 to 100 watts) and free of
dust. Hold a book or paper about 16 to 18 inches away from you and slightly
below eye level. Reading when lying on your back in bed or propped up on an
elbow may strain the eyes, and so will reading for long periods in a vibrating
vehicle. Avoid glare, of course.
And rest your eyes from time to time by
shifting focus, looking off into the distance. Night Blindness Inability to see
well or at all in dim light can mean something wrong not alone with the eyes
but with the entire system. Night blindness, as it is called, is a threat to
safety, particularly on the highway, because a driver may have 20/20 vision and
not realize that his vision is somewhat impaired at night. The condition
produces no discernible changes in eye tissues, so it cannot be diagnosed
unless the patient tells the physician that he has difficulty in reading road
signs at night or has trouble picking out objects in dimly lighted streets.
It
is not normal to have trouble seeing in dim light after a brief period, two to
three minutes, of adjustment. If you become aware of such a problem, discuss it
with your physician. It can be treated, sometimes simply by addition of vitaminA to the diet. Sunlight Good sunglasses can protect your eyes if you are in
bright sunlight. Poor ones may only add to your troubles if you wear them for long.
Don't wear glasses with scratches or irregularities. Some glasses are too
lightly tinted to do much good. It's true that good sunglasses are expensive.
The best have ground and polished lenses, and are worth the investment. Even
though you wear sunglasses, do not look directly into the sun. Don't wear the
glasses indoors and at night no matter how fashionable it may seem because
accidents result from the reduced visual perceptiveness. If you use regular
glasses, it is worthwhile to have a pair of sunglasses ground to your
prescription rather than clip a pair of possibly inferior sunglasses over your
carefully made regular glasses.
