Deciphering Near Vision Only and Distance Vision Only prescription
xesd
Can someone provide me a tutorial on how to order Near Vision (i.e.
'reading' ) glasses from my prescription? I have values on the
prescription for Sphere, Cylinder, Axis, and Add. As I understand
it, the 'Add' column is actually my near vision prescription (+1.5 for
both eyes, in my case). Can I just enter this into any of the on-line
sellers forms with the instruction 'Near Vision Only' ? Or should I
also fill in all the other values? Thanks for any information.
Doug Herr
It depends a bit on which seller.
Mine script is:
Sph Cyl Axis Add
-0.50 -0.25 165 +0.75 OD
plano -0.75 040 +0.75 OS
That would be entered just like that for bifocals/progressives.
Or for single vision non-reading it would look like:
Sph Cyl Axis
-0.50 -0.25 165
plano -0.75 040
Unless Zenni updated their form, you can't enter that info
directly to get reading glasses. You can convert it tho, which
then gives you:
Reading/Near:
Sph Cyl Axis
+0.25 -0.25 165
+0.75 -0.75 040
So, the "Add" values are added to the Sphere with nothing else
changing. This is where it is very important to understand the
negative values for near sighted and the plus values for far
sighted.
The best way for you to get good help here, is to post all the
prescription info you have and people can help to convert it if
needed.
powrwrap
> On Nov 14, 2:40 pm, Doug Herr <wombatz...@gmail.com> wrote:
> Mine script is:
>
> Sph Cyl Axis Add
> -0.50 -0.25 165 +0.75 OD
> plano -0.75 040 +0.75 OS
> Unless Zenni updated their form, you can't enter that info
> directly to get reading glasses. You can convert it tho, which
> then gives you:
> Reading/Near:
> Sph Cyl Axis
> +0.25 -0.25 165
> +0.75 -0.75 040
>
> So, the "Add" values are added to the Sphere with nothing else
> changing. This is where it is very important to understand the
> negative values for near sighted and the plus values for far
> sighted.
Pretty much what Doug said. Put another way, add the "add number" to
the *first* number (sphere) in each eye, leave everything else as is
and order it as a single-vision Rx. For readers you should use the
near PD value plus 1 mm, not the distance vision PD value.
(Alternatively, if you don't know the near PD measurement a good
approximation is to subtract 2mm from your distance PD)
Example, I am:
OD Cyl Axis Prism Base Add
-.75 Sph - - - +2.25
OS Cyl Axis Prism Base Add
-.75 Sph - - - +2.25
My pd is 67/64
So I ordered some readers that were:
OD Cyl Axis Prism Base Add
+1.50 Sph - - - -
OS Cyl Axis Prism Base Add
+1.50 Sph - - - -
Using a pd of 65.
Before I ordered I tried on readers of various powers at Walgreen's
and Wal Mart discovering that +1.50 was perfect. You might want to try
this also.
I ordered these readers along with two other pair of glasses from
Zenni four days ago. I was able to get the readers in decent frames
for $8.00 plus shipping ($1.65), whereas Walgreen's readers were
$27.99, Wal-Mart's were $19.97 and both stores models were in flimsy
frames. Also, drug store readers do not have axis and cylinder
adjustments.
powrwrap
> Pretty much what Doug said. Put another way, add the "add number" to
> the *first* number (sphere) in each eye, leave everything else as is
> and order it as a single-vision Rx.
prism as it is in your regular prescription but you would enter zero
for the Add portion of your prescription.