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How accurate is an auto lensometer?
My eyeglass prescription last year in my right eye is -.75. I ordered glasses. When I went to my eye exam a few days ago, the doctor put my glasses in the auto lensometer and the machine said the prescription was -.50. He retested it several times. Is the machine a little off or was the lens made incorrectly?
1 Answer
- TigerLv 58 years agoFavorite Answer
Well built auto lensometers have an accuracy of +/- 0.25.
So the error is justified.
You should never rely upon lensometers to calculate your eye power, accurately. Instead, you should always perform a manual trial and error check with different lenses near an Optometrist.
