Is 0.25 a big difference in eye prescription?

For the nearsighted, the American Optometric Association (AOA) has determined the following levels of severity: If your number is between -0.25 and -2.00, you have mild nearsightedness. If your number is between -2.25 and -5.00, you have moderate nearsightedness.

What is a high astigmatism prescription?

A high astigmatism refers to the numbers on your contact lenses or glasses prescription. Generally, the higher the number for the axis and cylinder on your prescription, the stronger your astigmatism is. The picture below depicts how viewers with severe astigmatism would see.

What is normal CYL in eye prescription?

The abbreviation stands for Cylinder. It represents the amount of lens power you need for astigmatism. If you do not have astigmatism, you may not have anything indicated in this column. The value may be a plus or a minus, and in most cases, the value will be between +/-0.25 to +/-4.00.

What base curve should I choose?

The most basic rule is that you always want the base curve to be as close to +6.00 as you can get and still have the Rx work. The more minus the power (less plus power to minus power) the lower plus the base curve will become. A high minus Rx may even have a base curve of +0.25 or even 0.00.

What do the numbers mean on my Prescription for astigmatism?

Astigmatism –The second number in your prescription identifies what degree of astigmatism you have i.e. how well or poorly your eye focuses light onto the retina. The number can be written either with a (+ sign) or a (- sign). This number is called your cylindrical correction. Axis – The third number indicates the direction of your astigmatism.

How do I know if my astigmatism is vertical or horizontal?

Axis – The third number indicates the direction of your astigmatism. For example, an axis of 180 degrees means the astigmatism is horizontal. If your prescription doesn’t have a second or third number, you most likely don’t have astigmatism.

What does the ‘sphere’ number on my eye chart mean?

This number denotes whether you are nearsighted (the ‘Sphere’ number will be negative) or farsighted (the ‘Sphere’ number will be positive). If the absolute value of the ‘Sphere’ number is 4.00 or lower, the number is left as is.

What is the cylinder for contact lenses for astigmatism?

Contact lenses for astigmatism only become available at ‘Cylinder’ values of -0.75 or higher. So what happens when the Cylinder on your glasses prescription is -0.25 or -0.50?