Author Topic: Calibration Ball  (Read 608 times)


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Calibration Ball
« on: August 15, 2019, 08:57:57 pm »
If you measure the calibration ball as though it was a patient's eye, should it not measure as a sphere with radius of 8.00mm and an eccentricity of 0.00 no matter what chord you select?

Yes, mine measures a curvature of 8.00mm, but has an eccentricity on the main screen of 0.04 and if you use the analysis function, the eccentricity can go up up to even 0.2 depending on what chord you select. And does that mean if we're entering eccentricity values into 3rd party software to calculate an ortho K lens for us, we have to be a bit wary? If the ball measures with an eccentricity of 0.04 should we subtract 0.04 when we enter e values into 3rd party software?

And yes, I have calibrated before doing these measurements.

So just curious.


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Re: Calibration Ball
« Reply #1 on: September 25, 2019, 03:32:44 pm »
Hi Trevor,

Our apologies for the late reply.  I have passed on your query to our development and engineering team who will get back to you here shortly.

Kind regards,