mangled_us[at]yahoo.com wrote:
- quote -

Whoever supplies your glasses will figure that out for you, but, to
repeat, add "sphere" and "add" together:

Single vision readers:
R +1.25
L + 1.75

- quote -


Yes. As you can see above, each eye needs a different power.

If you were thinking of over the counter readers, you could try +1.50
which will be a little off for each eye.

Dr Judy



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- quote -

Doh !

It should have been :

R : SPH +0.75, ADD +0.50
L : SPH +1.25, ADD +0.50

ie the left SPH is slightly more than the right.

....snip comprehensive reply...

- quote -

Thanks for the reply, the optician did say I had slight farsightedness
and also Presbyopia. How can I tell from those numbers what strength
of reading glasses I need ? Does it make any difference that the value
of SPH is differend fro the right and left eyes ?

Thanks again,

David

<mangled_us[at]yahoo.com> wrote in message
news:1155069852.773370.71480[at]n13g2000cwa.googlegroups.com...
- quote -

do a Google search using these search terms (all at once):
sphere cylinder axis

mangled_us[at]yahoo.com wrote:

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I'll take a shot, but I'm not a doctor. SPH means "spherical"
correction, also known as "power". Plus numbers mean farsighted. Plus
lenses make close things optically farther, thus they are also used for
reading glasses. The ADD part is the bifocal or progressive part of
the prescription - it's the amount of additional plus power added at
the bottom of the lens to be used for reading or close work.

I think +0.75 would be considered mild farsightedness. The ADD part if
generally for people with presbyopia, where they can't accomodate as
much (your eyes accomodate from distance to close; with perfect eyes or
eyes corrected properly, the eyes are relaxed at distance. They "work"
for close up, and this ability degrades with age).

Negative SPH would indicate nearsightedness, the inability to focus far
away. CYL is there to correct astigmatism, where the power required is
different in different orientations. The AXIS indicates the
orientation.

Hope this helps. Like I said, I'm no doctor, so one might chime in if
I made a mistake.

--

mangled_us[at]yahoo.com wrote:
- quote -

You are mildly hyperopic/farsighted (+.75 sph) with a very
mild amount of presbyopia (inability to accommodatefocus
at near as we get into the 40's) though I suspect the add +.50 is
incorrect (probably more likely it is written +1.50 add).
Regardless, your prescription is pretty mild.

frank

mangled_us[at]yahoo.com wrote:
- quote -

"Sph" is specifying the sphere power for your distance glasses. If you
remember any of your high school physics, the + sign means that you
need a convex lens. The "add" is the additional power needed at near,
again + sign means you need a stronger convex lens at near (40 cm).
Usually this is because you are over forty and have had the natural
aging loss of focusing power at near but sometimes an add is used to
correct muscle imbalances or focusing problems in younger people. If
you add together the distance sphere and the near add you get the total
power for reading glasses.

"Cyl" is the astigmatism power, "axis" is the direction of the
astigmatism, Inter -ADD is intermediate additional power (example
would be for computer distance of 60"), LPrism is prism for left eye
(used to correct minor muscle imbalances), R is right eye, H is
horizontal prism, V is vertical prism. They are blank because you
don't have those problems. Not sure about BVD, VD is usually vertex
distance which is the distance between your eyes and the trial lenses
when you had your eye test. With a low power like yours VD is not
relevant.

Your doctor should have explained what your problems were (what all
that means) and why you need glasses, if not, call back and ask. But
if he told you that you need readers and why, then the prescription is
simply the way to tell the glasses fabricator what power of lenses to
use.

For info see:

http://www.opto.ca/en/public/04_eye_...e_diseases.asp


Dr Judy

mangled_us[at]yahoo.com wrote:
- quote -


It means as you get older, presbyopia has become apparent. Youve been
prescribed bifocals so you can see things up close. You could just buy
$8 reading glasses if you dont need or want bifocals. Much easier with
regular readers for the computer

Hi,

I've just had my eyes tested for the first time in years and I've been
told I need reading glasses. I'm curious to know what the prescription
means, and it states aas follows :

R : SPH +0.75, ADD +0.50
L : SPH +0.75, ADD +0.50

There are other fields for CYL, Axis Inter-ADD and BVD but these are
blank, there also seems to be a whole section with LPrism and RPrism,
H-Dist, V-Dist H-Near and V-Near which has no entries at all.

Can anyone tell me what this all means or point me to a website where
all this is explained ? (I particularly want to know what SPH and ADD
mean).

Thanks,

David