Author Topic: Elimination of extra convergence induced by reading glasses  (Read 1860 times)

Offline johnlink

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Elimination of extra convergence induced by reading glasses
« on: February 22, 2013, 12:52:13 PM »
I understand from http://www.myopia.org/prismaticeffect.htm that reading glasses increase the convergence required, and there is a suggestion that the convergence could be reduced by using lenses whose centers are closer together than the distance between the pupils. Have any of you used reading glasses that are decentered in this way? How might one determine the optimal amount of decentering?

John Link

Offline OtisBrown

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Re: Elimination of extra convergence induced by reading glasses
« Reply #1 on: February 22, 2013, 05:24:43 PM »

Hi John,

I am pleased your asked that question.  The best approach is to measure your P.D., and that will give you your correct "centering".

Since I am now wearing a plus lens (to protect my distant vision) I consider ANY "prismatic effect" to be benifical to my "convergence" - if that were a concern.  I find that over-the-counter "plus" glasses work just fine. But if you are concerned, just measure your P.D., and order your lenses from Zennioptical.com - as I do.  Good luck!

I understand from http://www.myopia.org/prismaticeffect.htm that reading glasses increase the convergence required, and there is a suggestion that the convergence could be reduced by using lenses whose centers are closer together than the distance between the pupils. Have any of you used reading glasses that are decentered in this way? How might one determine the optimal amount of decentering?

John Link

Offline johnlink

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Re: Elimination of extra convergence induced by reading glasses
« Reply #2 on: February 23, 2013, 07:31:01 AM »

Hi John,

I am pleased your asked that question.  The best approach is to measure your P.D., and that will give you your correct "centering".

Since I am now wearing a plus lens (to protect my distant vision) I consider ANY "prismatic effect" to be benifical to my "convergence" - if that were a concern.  I find that over-the-counter "plus" glasses work just fine. But if you are concerned, just measure your P.D., and order your lenses from Zennioptical.com - as I do.  Good luck!


I plan to order from zennioptical, but I 'm wondering about the benefits of having the center of the lenses closer to each other than my pupillary distance. The discussion on http://www.myopia.org/prismaticeffect.htm seems to say that reading glasses increase the convergence required but that decentering the lenses can reduce the convergence needed.

John Link