Why is there a difference between axis given by doctor and autorefractometer?

Question

Hi doctor,

My cylindrical power in the right eye is -0.5 D and the axis of the power is coming 30 in the auto refractometer. But, my doctor prescribed me the axis of the power 180, and I could see even the smallest letters in the Snellen's chart with that glass. So, I want to know why there is a huge difference between the axis given by the auto refractometer and the axis given by my doctor?

Answer 1

Hi,

Welcome to icliniq.com.

You see, ten by ten or six by six mean the glasses are good and suitable. For the difference, actually, the difference is 30 and not 150 and I will explain it to you. The cylinder and its axis is a piece of the rod without base and head, both ends are same. Now imagine that you put this rod at axis 180, it is totally horizontal and it is at 0, for this the difference is 30. Why this differs from auto is because the autorefractor guides us, then there is an exam and we are trying lenses many times and sometimes it takes more than 10 minutes to have the prescription depending on the medical and physical rules. All of this auto and exam with trying gives us the last result. Otherwise, if the auto is better, you can do auto and give its result to the optician for glasses and often it will not be correct.