The EyeQue Personal Vision Tracker is able to measure refractive error in the following ranges:
Spherical measurement of +8.00D to –10.00D.
Cylindrical measurement of 0.00 to –4.00D.
Axis measurement from 1 to 180 in 1-degree increments.
If you typically have correction measurements outside of these ranges, you may not be able to measure your refractive error accurately. You will likely experience a warning while testing indicating that the range limit has been reached. Contact support@EyeQue.com for assistance.