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Prescription axis: 4 deg. vs. 175 deg.

MeWantBroadband · 2008-04-20 15:31:26

Hi, Anyone understand the geometry of the axis component of your eyetest? It relates to astigmatism, and it goes from 0 to 180 degrees. My prescription changed recently from 4 degrees (it was 3 degrees in the test before that) to 175 degrees. This is a 9 degree change, so is that significant, or 'sample error'? I would not…

20-04-2008 3:31pm

#1

MeWantBroadband

Registered Users, Registered Users 2 Posts: 189 ✭✭

Join Date: December 2005

Posts: 143

Hi,

Anyone understand the geometry of the axis component of your eyetest?

It relates to astigmatism, and it goes from 0 to 180 degrees.

My prescription changed recently from 4 degrees (it was 3 degrees in the test before that) to 175 degrees.

This is a 9 degree change, so is that significant, or 'sample error'?

I would not have imagined that the axis would change over time, unlike the strength of the subscription which changes as you get older.

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Comments

#2 21-04-2008 7:55pm

endplate

Registered Users, Registered Users 2 Posts: 991 ✭✭✭

Join Date: May 2004

Posts: 932

The axis change is very small it's probably more to do with the type of equipment used to determine your prescription. It's nothing to worry about

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