How do you read this eye glasses and contacts prescriptions?

While medical practitioners used to write their prescriptions in Latin, eye doctors seem to write their eyeglass or contact lens prescriptions in code! For those who are curious and want to crack the code, here is the simple explanation of the coded numbers and letters.

This is how a blank eyeglass prescription may look:
Eye Prescription RX

R and L on the left refer to the right and left eye.

Sph is the power you need in order to see clearly. A '+' is for far sighted and magnifies an object, and a '-' is for near sighted and will minimize an object. This is the main correction.

Cyl shows the power you need to correct astigmatism. This is the fine tuning of the lens.

Axis tells the manufacturer of the lens where the power to correct the astigmatism should be placed. It refers to the eye on a 360 degree axis.

Add is the power of the reading correction. This is additional information to the Sph box as this power needs to be added to the Sph to get the actual power.

How do you read this eye glasses and contacts prescriptions?

Prism/Base. This box is only used for people who are seeing double and have eye teaming problems. Other information which may be included is DV for distance vision. This specifies the part of the prescription designed to improve far vision. In bifocals this would usually be in the top segment.

NV refers to near vision and is the same as Add. Where a single vision lens is prescribed to improve close work this is the refractive power to be added to the sph of each eye.

OD is the abbreviation of the Latin oculus dexter, which means right eye.

OS is the abbreviation of the Latin oculus sinister, which means left eye.

PD is the Pupillary distance between pupils. This is necessary information to make glasses to center the pupils in the lens for proper optical centers. This covers the actual prescription for eyeglass correction and is used all over the world. The lower tick boxes are for additional and superficial instructions when having the eyeglasses made. The patient usually opts for these at an additional cost.

Anti-reflective Coating helps cut off glare from the sun and bright lights by reducing reflection. It also helps with cutting off glare from on coming headlights while driving at night and decreases glare while working in front of a computer screen.

Polycarbonate is a very strong substance which is also ultra-light. Glasses are made of this for those who are concerned about the weight of the glasses, particularly if the lenses are thick and heavy. Children under the age of 18 are required to have this option because it is impact resistant and contains UV protection.

High Index Plastic can be used to create thinner lens which again are lighter than traditional materials.

Transitions/Sunglasses means the lens will react to sunlight and darken in response. The lens interacts with direct UV interaction and is useful for those living in sunny areas who move in and outdoors frequently.

Single Vision is one vision; the entire lens is one prescription.

Bifocal refers to a lens which is split; usually the lower half moon is for reading and the upper part of the lens is for long distance viewing.

No-Line Progressive relates to a bifocal lens; also known as multifocal lenses. The prescription is graduated from distance, at the top of the lens, to near, at the bottom of the lens and everything in between.

Readers/Computer refers to glasses which may not be worn permanently or outdoors. They need to be sturdier for being frequently taken on and off, but are not likely to be worn outdoors or for sport.

A Contact Lens Prescription looks like this:

Contact Lens Prescription

Once again R and L refers to each eye separately.

Lens Name refers to a brand name of the contact lenses.

BC refers to the curvature of the lens. It can be loose or tight.

Dia refers to the size or diameter of the contact lens.

Sph is the power you need in order to see clearly. A '+' is for far sighted and a '-' for near sighted. This is the main correction.

Cyl shows the power you need to correct astigmatism. This is the fine tuning of the lens.

Axis tells the manufacturer of the lens where the power to correct the astigmatism should be placed. It refers to the eye on a 360 degree axis. The information on a contact lens prescription is very different to an eyeglass prescription. With contact lenses the doctor has to specify the curve and the overall size of the lens. They show different measurements because eyeglasses sit some distance in front of the eye while contact lenses are right on the eye itself.

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alexa

It was wondering if I could use this write-up on my other website, I will link it back to your website though.Great Thanks.