Q: Do autorefractors need to be calibrated?

A: It must become a good habit for the optician or ophthalmologist to periodically

check the accuracy of an instrument as important as the auto refractometer. We

can carry out the verification both in the laboratory and at home and we issue a

document certifying the accuracy of the instrument.The principle is known as

the optometer principle. This instrument gives the leverage of power variation

in the refracting apparatus. The autorefractors using this principle have a single

converging lens placed at the focal length distance from the eye instead of interchangeable trail lenses.