How different are these two prescriptions?

Discussion in 'Glasses' started by NumbersGuy, Sep 12, 2017.

  1. NumbersGuy


    Sep 12, 2017
    Likes Received:
    My wife's distance prescription from 2014:

    OD +.75 -1.50 90
    OS -.50 -1.00 95

    Today she was measured at:

    OD -1.50 +1.75 178
    OS -1.50 +1.25 010

    At first glance it looks extremely different. But then I noticed that the two CYL measurements were actually very similar, looking different only because of the choice of convention used (+ vs. -). Since the second Axis angle are nearly perpendicular to the first Axis angles, I would expect the diopters to be negated.

    We have not yet purchased glasses based on this prescription. My question is, does the choice of presentation for astigmatism affect the comparative interpretation of the spherical? That is, are they really all that different?
    NumbersGuy, Sep 12, 2017
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.