sunglasses are most important during summer because it protects
your eye from the harmful uv-rays that are the cause of blindness;
Points to consider while choosing
Always look for sunglasses that block 99 or 100 percent of
UV radiation thereby protecting your eyes.
Also see to it that the lenses are dark enough to filter out
75 to 90 percent of the powerful sunrays that makes you squint.
The lenses should not cause eyestrain, headache, and, give
Note: One way to ensure that the sunglasses will protect
your eyes from harmful rays is to put your sunglasses on,
and take a look in the mirror; if you can see your eyes, the
lenses aren't dark enough to screen out visible light.
Use colours of your lenses that will
help you see the world's true colour i.e., grey, brown, or
green. Avoid yellow or amber lenses they make it hard to distinguish
the traffic signal.
If you are buying plastic lenses then pick one that has a
Try to go for wraparound frames since they offer the most
protection by blocking light from the sides, top, and bottom.
Go for frames that are strong, sturdy as well as light. Nylon
or composite frames are light and strong; metal frames tend
to be fashionable but are often heavy and inflexible.
Types of sunglasses
Single-gradient lenses: these
are permanently shaded from top to bottom, cut glare from
above but allow you to see clearly below.
Double-gradient lenses are those,
which are dark on the top and bottom and lighter in the middle.
Polarized lenses are also great
for all these activities, since they block light reflected
off smooth surfaces like water and pavement.
Photo chromic lenses; they darken
in bright light in about 30 seconds but take about five minutes
to lighten up again in dimmer conditions. Good if you are
going in and out of the house the whole day.