Oops, I just went back and reread your post. Reading glasses need a
little math. Single vision *distance* are even easier.
You just drop the ADD (reading part) from the prescription, and order
them with your regular PD value.
Same example prescription:
SPH: 1.00
CYL: 0.50
AXIS: 75
ADD: +2.00
This translates into:
SPH: 1.00
CYL: 0.50
AXIS: 75
ADD: 0
-- Chuck Knight
On Thu, Jun 11, 2009 at 10:19 AM, Chuck Knight<[email protected]> wrote:
> Gee, thank you for the compliment! But, I'm surprised that my posts
> have created hesitation...they're intended to have the opposite
> effect.
>
> Anyway...reading glasses are easy. You have 4 numbers on your
> prescription, for each eye...
> SPH, CYL, AXIS, ADD.
>
> SPHere is the distance correction.
> CYLinder is the astigmatism correction
> AXIS is the twist needed to correct the astigmatism
> ADD is the extra help you need for reading
>
> To generate a single-vision reading prescription, you need only sum
> the SPH and ADD values, and enter the result into the SPH field.
> Leave the CYL and AXIS the same, and leave the ADD blank. And,
> subtract 3mm from your PD...unless you have a measured reading PD.
>
> Let's use an example prescription.
> SPH: 1.00
> CYL: 0.50
> AXIS: 75
> ADD: +2.00
>
> To convert this, you would sum 1.00 and +2.00 for a total correction
> of 3.00, and the resulting prescription would be:
> SPH: 3.00
> CYL: 0.50
> AXIS: 75
> ADD: 0.00
>
> Be sure to remember to subtract 3mm from your distance PD, for your
> reading glasses.
>
> -- Chuck Knight
>
>
>
>
> On Wed, Jun 10, 2009 at 10:19 AM, Chris Gallucci<[email protected]> wrote:
>>
>> First, let me say WOW, what a resource! I wish I had known about this
>> back when I laid out some large coin for a pair of Oakleys Why 4 w/
>> photochromatic single vision lenses. I've spent the last 2 days
>> gourging myself on this board and the blog.
>>
>> On to my issue -- I have a new Rx for progressive lens but the local
>> B&Ms are giving me fits about replacing the lenses with new lenses of
>> my choosing. So I'm going online.
>>
>> Chuck Knight's most helpful and informative posts have lead me to
>> hesitate ordering progressives online, at least until and I can get a
>> more thorough and complete Rx written. So I want to start my online
>> ordering experience by getting single vision glasses. Plus all I need
>> is single vision for my sunglasses.
>>
>> So my question is, do I need to do any conversion factor to my Rx for
>> single vision? Or do I just drop the "add"?
>> Sorry I don't have my Rx handy but my "add" is +1.25 for both eyes.
>>
>> TIA, ChrisG
>>
>> >>
>>
>
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