You can measure the distance yourself by looking in a mirror or you can have a friend do it. Measure the distance between the center of your pupils. PD is the distance from the center of the pupil (black circle) in one eye to the center of the pupil in the. Place a ruler on the bridge of your nose.Ģ. In this case each value refers to the distance from the middle of your nose to the middle of the eye.ġ. Some prescriptions may show two PD values - a Right PD and a Left PD. This value is usually a single number and refers to the distance (in millimeters) from the middle of one eye to the other. Pupillary Distance (PD) - Your eyeglass prescription may also include your pupillary distance. This value is used for contact lenses and is not required for eyeglasses.ĪDD power - This value indicates the additional amount of power required to ensure clear vision at a close range and is used for for individuals with presbyopia. This value is used for contact lenses and is not required for eyeglasses.ĭIAMETER - The diameter (measured in millimeters) is the distance from one edge of the lens to the other. The base curve of a lens (measured in millimeters) indicates the curvature on the inside of the contact lens. The Axis is displayed in degrees and is required for lenses that correct astigmatism.ī.C. The higher the number, the more astigmatism you have.ĪXIS - The Axis value also refers to astigmatism and tell you the orientation of the astigmatism. On some prescriptions the SPH may also be referred to as "Sphere", "Power" or "PWR".ĬYL - The Cylinder value measures the degree of astigmatism that you have and the strength needed to correct it. A minus (-) sign means that the prescription if for nearsightedness (myopia) and a plus (+) sign means that the prescription is for farsightedness (hyperopia). SPH - The spherical power is the most common value contained in almost all prescriptions and it refers to the amount of distance vision correction needed. When you need glasses, an optometrist or an optician will measure this distance to. Retrieving your pupillary distance is typically done by your eye doctor or specialist. Pupillary distance is the space measured in millimeters (mm) from the center of one pupil to another. On some prescriptions the right and left eyes may simply be referred to as "R" and "L". Pupillary distance (PD) is the distance between your pupils. "O.D." refers to the right eye and "O.S." refers to the left eye. The OD and OS values tell you for which eye the prescription is for. binocular PD measurements There are two types of pupillary distance measurements: Monocular PD. Pupillary distance can vary widely roughly between 51 mm and 74.5 mm for women and 53 mm and 77 mm for men. Download our free ruler and save 70 off of retail prices. The average pupillary distance for an adult is about 63 mm, but this is not a number you’ll want to assume. Please note that your prescription may not include all the values listed above and some boxes may be blank. Learn how to measure the distance between your pupils to order a new pair of glasses online. How Important Is Pupillary Distance Without PD it is impossible to purchase an accurate pair of glasses as it pronounces the optical center of both pupils.
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