What do the numbers on my optical prescription mean?

In general, the further away from zero the number on your prescription, the worse your eyesight and the more vision correction (stronger prescription) you need. A “plus” (+) sign in front of the number means you are farsighted, and a “minus” (-) sign means you are nearsighted.

Is a 3.0 prescription bad?

Generally, the further away from zero (+ or -), the worse the eyesight. A number between +/-. 025 to +/-2.00 is considered mild, a number between +/-2.25 to +/- 5.00 is considered moderate, and a number greater than +/- 5.00 is considered severe. Eye prescriptions can change over time.

How do you read astigmatism prescription?

The minus sign is for nearsighted astigmatism and a plus sign for farsighted astigmatism. Axis: Indicates the direction of astigmatism. For example, if the axis is 180 degrees the astigmatism is horizontal. Add: Indicates the magnifying power applied to the bottom of multifocal lenses to correct presbyopia.

What does ax mean on contacts?

astigmatism
Axis (AX): As astigmatism is caused by the irregular curvature of the eye, the axis is a figure which determines the angle of the correction needed in order to see clearly. The Axis is always a number between 0 and 180 degrees.

What is considered a high astigmatism?

Mild Astigmatism <1.00 diopters. Moderate Astigmatism 1.00 to 2.00 diopters. High Astigmatism 2.00 to 4.00 diopters. Extreme Astigmatism > 4.00 diopters.

What do the numbers on my eye prescription mean?

This prescription shows that the patient is hyperopic and needed a plus eye lens to correct their vision. Throughout your eye examination, your Optometrist will take an accurate note of the values measured for each eye. This is the number you might recognise.

How do optometrists measure power of the eyes?

Throughout your eye examination, your Optometrist will take an accurate note of the values measured for each eye. This is the number you might recognise. If you wear glasses, you probably know your lens power number, either minus eye power or plus eye power.

What do the numbers in front of my eye chart mean?

A “plus” (+) sign in front of the number means you are farsighted, and a “minus” (-) sign means you are nearsighted. These numbers represent diopters, the unit used to measure the correction, or focusing power, of the lens your eye requires.

What is a 20/200 visual acuity equivalent to a prescription?

A visual acuity of 20/200 is roughly equal to a prescription of -2.50 diopters. Eye doctors can’t convert visual acuity (like 20/200) to an exact prescription, they can only give you a rough idea. Many different uncorrected prescriptions can yield a visual acuity of 20/200. The only way to know for sure is to have your eye doctor check.