WAYS TO READ YOUR EYE PRESCRIPTION CORRECTLY
An eye prescription holds the readings that your optometrist records each time you go for an eye test. These numbers on the prescription slip/card are the key to your correct power. Whenever you wish to buy Prescription Eyeglasses/sunglasses, these values come in handy. It might look tricky at first, but there’s an easy way to decode these abbreviated terms & set of +/- readings.
Let’s start with the basics -
- + indicates long-sightedness or Hyperopia
- - indicates correct near-sightedness or Myopia
- RE/ O.D. stands for Oculus Dexter or Right Eye
- LE/ O.S. stands for Oculus Sinister or Left Eye
- PD is Pupillary Distance
- DV stands for Distance Vision
- NV stands for Near Vision
Let’s go ahead and know in detail what do the other terms in your eye prescription mean:
Sphere (SPH)
SPH or Sphere is the power of the lens required to correct a single vision defect. This denotes if a person has myopia or hyperopia. It is measured in Diopters (D). The values can be different for both the eyes.
- Corrects Myopia & Hyperopia
- Ranges from 0.00 to +/- 20.00 D
- Higher prescription means high degree myopia/hyperopia
Cylinder (CYL)
CYL or Cylinder power indicates that the cornea of the eye is not perfectly sphere in shape. If you have some numbers in your CYL grid of your prescription, you will require eyeglasses to correct astigmatism.
- Corrects Astigmatism
- Ranges from 0.00 to +/- 4.00 D
- Higher prescription means high degree astigmatism
Axis
Axis reflects the exact orientation of your astigmatism. It is measured in Degrees. If your prescription has a CYL value, it is sure to have an axis value too. If your prescription holds a CYL value and no axis or vice versa, it means your prescription is either incomplete or incorrect
- Indicates degree/direction of astigmatism
- Ranges from 0 to 180 Degrees
- Always present along with Cylinder Value
ADD (Addition)
Add or Near Addition power is added on the lower part of the multifocal/bifocal lenses to correct presbyopia. This helps one in performing close-up tasks with ease.
- Indicates the additional reading power
- Used in bifocals, progressives and reading glasses
- Added at the bottom half of the lens for people with presbyopia
Pupillary Distance (PD)
Pupillary distance is an important measurement from the center of one eye to the center of another. This is used to mark the exact optical center in your lenses which further helps to view things properly and without any eye strain.
- Distance between the centers of two pupils
- Ranges from 50 to 70 mm
- Incorrect PD value can cause eye strain & visual distortion
Sphere (SPH)
SPH or Sphere is the power of the lens required to correct a single vision defect. This denotes if a person has myopia or hyperopia. It is measured in Diopters (D). The values can be different for both the eyes.
- Corrects Myopia & Hyperopia
- Ranges from 0.00 to +/- 20.00 D
- Higher prescription means high degree myopia/hyperopia
Cylinder (CYL)
CYL or Cylinder power indicates that the cornea of the eye is not perfectly sphere in shape. If you have some numbers in your CYL grid of your prescription, you will require eyeglasses to correct astigmatism.
- Corrects Astigmatism
- Ranges from 0.00 to +/- 4.00 D
- Higher prescription means high degree astigmatism
Axis
Axis reflects the exact orientation of your astigmatism. It is measured in Degrees. If your prescription has a CYL value, it is sure to have an axis value too. If your prescription holds a CYL value and no axis or vice versa, it means your prescription is either incomplete or incorrect
- Indicates degree/direction of astigmatism
- Ranges from 0 to 180 Degrees
- Always present along with Cylinder Value
ADD (Addition)
Add or Near Addition power is added on the lower part of the multifocal/bifocal lenses to correct presbyopia. This helps one in performing close-up tasks with ease.
- Indicates the additional reading power
- Used in bifocals, progressives and reading glasses
- Added at the bottom half of the lens for people with presbyopia
Pupillary Distance (PD)
Pupillary distance is an important measurement from the center of one eye to the center of another. This is used to mark the exact optical center in your lenses which further helps to view things properly and without any eye strain.
- Distance between the centers of two pupils
- Ranges from 50 to 70 mm
- Incorrect PD value can cause eye strain & visual distortion
-
Sphere (SPH)Sphere or SPH is the power of the lens required to correct a single vision defect. This can be for myopia and hyperopia. It is measured in Dioptres. The prescription can differ for both the eyes.
-
Cylinder (CYL)Cylinder power indicates that your eyes are not perfectly sphere in shape. If you have some numbers in your CYL column of your prescription, you will require eyeglasses to correct astigmatism.
-
AxisAxis reflects the exact orientation of your astigmatism. It is always present along with your CYL prescriptions. If your prescription holds a CYL value and no axis or vice versa, it is incomplete.
-
ADD (Addition)Add or Near Addition power is added on the lower part of the multifocal/bifocal lenses to correct presbyopia. This helps one in performing close-up tasks with ease.
-
Pupillary Distance (PD)Pupillary distance is an important measurement from the center of one eye to the center of another. This is used to mark the exact optical center in your lenses which further helps to view things properly and without any eye strain.
- Sphere (SPH)
Sphere (SPH)
Spherical error, or overall power of lens is the basic part of your prescription. A (+) indicates farsightedness and a (-) indicates nearsightedness. - Cylinder (CYL)
Cylinder (CYL)
Cylinder value indicates astigmatisms or perpetually blurry vision. - Axis
Axis
To make your vision impeccable, we use a degree between 1 and 180 to tell us your astigmatism axis orientation. - ADD (Addition)
Axis
This number is sometimes written NV for Near Vision and is used in multifocal lenses and readers.
- Right Eye (OD) *
- Left Eye (OS) *
- Additional Information
- Pupillary Distance (PD): *
- Corrects Myopia & Hyperopia
- Ranges from 0.00 to +/- 20.00 D
- Higher prescription means high degree myopia/hyperopia
- Sphere (SPH)
Sphere (SPH)
Spherical error, or overall power of lens is the basic part of your prescription. A (+) indicates farsightedness and a (-) indicates nearsightedness. - Cylinder (CYL)
Cylinder (CYL)
Cylinder value indicates astigmatisms or perpetually blurry vision. - Axis
Axis
To make your vision impeccable, we use a degree between 1 and 180 to tell us your astigmatism axis orientation. - ADD (Addition)
Axis
This number is sometimes written NV for Near Vision and is used in multifocal lenses and readers.
- Right Eye (OD) *
- Left Eye (OS) *
- Additional Information
- Pupillary Distance (PD): *
- Corrects Astigmatism
- Ranges from 0.00 to +/- 4.00 D
- Higher prescription means high degree astigmatism
- Sphere (SPH)
Sphere (SPH)
Spherical error, or overall power of lens is the basic part of your prescription. A (+) indicates farsightedness and a (-) indicates nearsightedness. - Cylinder (CYL)
Cylinder (CYL)
Cylinder value indicates astigmatisms or perpetually blurry vision. - Axis
Axis
To make your vision impeccable, we use a degree between 1 and 180 to tell us your astigmatism axis orientation. - ADD (Addition)
Axis
This number is sometimes written NV for Near Vision and is used in multifocal lenses and readers.
- Right Eye (OD) *
- Left Eye (OS) *
- Additional Information
- Pupillary Distance (PD): *
- Indicates degree/direction of astigmatism
- Ranges from 0 to 180 Degrees
- Always present along with Cylinder Value
- Sphere (SPH)
Sphere (SPH)
Spherical error, or overall power of lens is the basic part of your prescription. A (+) indicates farsightedness and a (-) indicates nearsightedness. - Cylinder (CYL)
Cylinder (CYL)
Cylinder value indicates astigmatisms or perpetually blurry vision. - Axis
Axis
To make your vision impeccable, we use a degree between 1 and 180 to tell us your astigmatism axis orientation. - ADD (Addition)
Axis
This number is sometimes written NV for Near Vision and is used in multifocal lenses and readers.
- Right Eye (OD) *
- Left Eye (OS) *
- Additional Information
- Pupillary Distance (PD): *
- Indicates the additional reading power
- Used in bifocals, progressives and reading glasses
- Added at the bottom half of the lens for people with presbyopia
- Sphere (SPH)
Sphere (SPH)
Spherical error, or overall power of lens is the basic part of your prescription. A (+) indicates farsightedness and a (-) indicates nearsightedness. - Cylinder (CYL)
Cylinder (CYL)
Cylinder value indicates astigmatisms or perpetually blurry vision. - Axis
Axis
To make your vision impeccable, we use a degree between 1 and 180 to tell us your astigmatism axis orientation. - ADD (Addition)
Axis
This number is sometimes written NV for Near Vision and is used in multifocal lenses and readers.
- Right Eye (OD) *
- Left Eye (OS) *
- Additional Information
- Pupillary Distance (PD): *
- Distance between the centers of two pupils
- Ranges from 50 to 70 mm
- Incorrect PD value can cause eye strain & visual distortion
Astigmatism
Single Vision - Myopia
Astigmatism
Single Vision – Myopia
Bifocal / Progressive
Bifocal / Progressive
Bifocal / Progressive
Bifocal / Progressive
PRESCRIPTION FOR CONTACT LENSES
A prescription for Prescription Eyeglasses/Sunglasses is different from that of Contact Lenses. Since contact lenses are placed on the eyes, in direct contact, the values are changed accordingly by your optometrist to give you utmost vision clarity and wearing comfort. So, it is advised to not use the same prescription for both contact lenses and powered eyewear. Do let your optometrist know that you’re switching to either one of them so that he can correctly record your eye power.