An auto-refractor measures the near-final prescription for glasses for the best distance vision. This near-final prescription is then delivered directly into an auto-phoropter via a computer cable. The final results require the doctor’s subjective interpretation.
Several features of an auto-refractor are:
- Spherical power range is available in plus and minus.
- Cylinder power can be expressed in plus or minus cylinder.
- Axis reading is available from 1 degree to 180 degrees.
- Accurate inter-pupillary distances are given in the readout. This is very beneficial in fitting monocularly sighted patients, patients with special needs, and infants, and can be incorporated into the prescription for glasses.
- Vertex distance is automatically measured in some of the units and also may be incorporated into the final prescription.
- Pupil size can also be measured and is useful in fitting rigid lenses and refractive surgery candidates.