Do you use it ?

How to Read Contact Lens
Power. . .
Reading contact lens
prescriptions can be daunting;
understanding them can be
more so.
With a little help, you
can read the power of your
contacts, and understand what it means, to help you
be come
better informed.
Difficulty: Moderately Easy Things
You'll Need:
Prescription label on contact
lens box
Contact lens power chart
Snellen Chart
Instructions Reading the contact lens
power

1. On the contact lens box,
read the prescription
information from left to
right. The prescription
should unfold in the
following way: Eye, Power (sphere), BC, Dia
and Brand.
The Eye column will contain either OD, OS or OU,
which mean right eye,
left eye or both eyes, respectively. This tells
you what eye the
prescription is for.

2. Read the next column,
which will be the power
of the contact for that
eye. Power is measured
from 20.00 to +20.00 (in
dioptres), and this equates to the amount of
compensation needed in
the eye. It basically
reflects the extent of the
near sightedness/myopic
(a negative number) or farsightedness/
hyperopic (a positive
number)
.
3. Read the following chart
to understand what your
power or sphere means
(obtained from
mdsupport.org):

Snellen----Estimated Prescription
20/10____
Plano (zero/0)
20/15____
Plano 20/20____Plano to
-0.25
20/30____-0.50
20/40____-0.75 20/50____
-1.00 to -1.25
20/100___ -1.75 to -2.00 20/200___
-2.00 to -2.50
These are
the most commonly used
powers.
If your power
was in the positives
(meaning you are farsighted), then the
snellen chart ratio would
grow larger as opposed
to smaller.

4. Learn what the Snellen
chart means. When
having an eye test, one
eye is covered at a time,
and the vision is
recorded. In the Snellen ratio of 20/20 (what
we've categorized as
normal eyesight), the
first 20 is the distance of
the test-20 feet. The
second 20 is the distance a normal eye can see at
the test-20 feet. Thus,
20/20 is "normal"
eyesight. If, for instance,
your ratio is 20/40, then
your eye sees the test at 20 feet, where a norma l
eye could see it at 40
feet, and so on down the
list. Therefore, the
power of your contact
lens essentially tells you the compensation
needed for your eyes so
that they can see at
20/20.

Tips & Warnings
The prescription table on
your contact lenses may
vary greatly in style and
layout, but they all present
the same information. Just
look around for your power number, you are bound
to
find it...
These are little bit dizzy for a normal human being.. You will figure it out when u read it once more.....