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Dr. Rick
Dr. Rick, Board Certified MD
Category: Eye
Satisfied Customers: 11414
Experience:  Ophthalmology since 1994 with Retina sub-specialty interest
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I'm very confused about PD Originally I went to lense

Customer Question

I'm very confused about PD
Originally I went to lense crafters and bought computer glasses, more or less they were designed for 27" -30" crystal clear sight at this distance
The PD they provides was 33 and 30.50
Recently I went to a different doctor and was prescribed
Computer Glasses
reading Glasses
She put a PD of 64/61
I just ordered two pairs of glasses from Zenni Optical.
I thought I'd use the 33 and 30.5 on all glasses because it worked well on
my prior computer glasses.
Zenni's computer said that a difference of more then 2 on a PD wasn't allowable, so I put in the 64 and wrote them a note asking if they could do the 33 and 30.5
They wrote back and said yes but maybe not advisable.
I called my DR and she isn't in the office this week so she couldn't answer my question but the recptionist who I don't trust answered my questions.
She said that the PD of 64 was for driving glasses and when you add +2 turns it into progressives.
She said that the PD of 61 should be for reading glasses. And also for my computer glasses.
So I'm confused at this point in time. Any insights would be appreciated.
Submitted: 1 year ago.
Category: Eye
Customer: replied 1 year ago.
This is prescription for progressive
Prescription TypeProgressive (No-Line Multi-Focal)
OD - Right -4.0 Cyl -0.5 Axis 138.0 NV ADD 2.0
OS - Left -3.25 Cyl -0.75 Axis 95.0
PD 64.0
The question is do I leave it at 64 or should I put 33 & 30.50
Customer: replied 1 year ago.
The Computer Glasses are at
Prescription TypeSingle Vision
OD - Right -3.0 -0.5 138.0
OS - Left -2.25 -0.75 95.0
PDR:33.0 L:30.5Question is do I keep the PD at 33 and 30.5
or use the 2nd number 61 like the receptionist told me.
Customer: replied 1 year ago.
Posted by JustAnswer at customer's request) Hello. I would like to request the following Expert Service(s) from you: Live Phone Call. Let me know if you need more information, or send me the service offer(s) so we can proceed.
Expert:  Dr. Rick replied 1 year ago.

Hi. My name is***** and I am online and available to help you today. Thank you for your patience.

Question and answer is just one of the services I offer. I can also provide you with premium services, such as live telephone or skype consultation, at a small additional cost. Let me know if you are interested.

When you see the PDR and PDL that is just half of your PD. THe PD of 94 takes into account both your eyes. It is just a different way of writing down the same thing.

PD is measured in MM. As such you can see that the PD of 64 is only 0.5 mm different then the PD of (33 + 30.5 = 63.5)....not a significant variation.

For close vision your PD is smaller as your eyes point toward each other (converge) for near tasks.

So. What is the take home message?

Both PD numbers are the same; it is just that one system splits the entire PD number into two halves. You do not need to worry about this at all.

Does this make sense to you?

It's safe for you to press the positive feedback button now if you so desire. And, never fear, even after you press that button I'll still be right here to continue helping you, but, as I do work for tips, I want to make sure you are happy before rating me.

Dr. Rick MD FACS

Customer: replied 1 year ago.
You still haven't answered one question.For the computer glasses am I ok using the 33 30.5 PD
or should I be using the 61 PD?
Expert:  Dr. Rick replied 1 year ago.

For near you want the smaller number, so go with the 61.

Make sense?

I hope this information was helpful for you. But I do work for tips so I want to make sure you are happy with me before rating me. If you have another question on this or a related issue feel free to fire away. You may also receive an email survey after our chat, if you can please give me the top rating in all areas. It has been a pleasure to assist you today.

Thanks in advance,

Dr. Rick MD FACS