No one can see as well at night as in the daytime.
But as we get older these differences increase.
A 50-year-old driver may require at least twice as much
light to see the same thing at night as a 20-year-old.
What you do in the daytime can also affect your
night vision. For example, if you spend the day in
bright sunshine you are wise to wear sunglasses.
Your eyes will have less trouble adjusting to night.
But if you are driving, do not wear sunglasses at night.
They may cut down on glare from headlamps, but
they also make a lot of things invisible.
You can be temporarily blinded by approaching
headlamps. It can take a second or two, or even
several seconds, for your eyes to re-adjust to the dark.
When you are faced with severe glare, as from a
driver who does not lower the high beams, or a vehicle
with misaimed headlamps, slow down a little. Avoid
staring directly into the approaching headlamps.
Keep the windshield and all the glass on your vehicle
clean — inside and out. Glare at night is made
much worse by dirt on the glass. Even the inside of the
glass can build up a film caused by dust. Dirty glass
makes lights dazzle and flash more than clean
glass would, making the pupils of your eyes contract
repeatedly.
Remember that the headlamps light up far less of a
roadway when you are in a turn or curve. Keep
your eyes moving; that way, it is easier to pick out
dimly lighted objects. Just as the headlamps should be
checked regularly for proper aim, so should your
eyes be examined regularly. Some drivers suffer from
night blindness — the inability to see in dim light — and
are not even aware of it.
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