under cylinder on my glasses script it just says sph.

#Under cylinder on my glasses script it just says sph. series

This is generally written as a superscript triangle when written manually. Prism – This refers to the ‘prismatic power’ required to correct muscle imbalance, measured in prism dioptres. This power is then added to the main prescription to formulate the reading prescription. Typically, the power varies from +0.50 to +4.50 (in extreme cases). Patients over the age of 40 are most likely to have this component present in their prescription, known as Presbyopia. AN AXIS MUST BE ACCOMPANIED BY ASTIGMATISM.Īdd – This corresponds to the added power of magnification required to correct our reading. If no astigmatism is required in the prescription, then an axis will not be present. if 90 appears on the prescription, then this corresponds to the vertical meridian of the eye, and if 180 appears, then it corresponds to the horizontal meridian of the eyes. The axis is defined from 0 - 180, just like a mathematical protractor for measuring angles. This is commonly referred to as ‘a rugby ball shaped eye.’ Not all patients need an extra correcting power so it’s presence maybe limited.Īxis – The axis pertains to the direction of the astigmatism. The optical surface of our eyes may not be fully spherical and irregularly shaped therefore an extra lens power is necessary to correct the aspherical nature of our cornea. However if it’s preceded by a (-) sign, then it means that you are generally ‘short-sighted’.Ĭylinder (Cyl) – This term refers to any ‘astigmatism’ that may be required to correct your eyes fully. If the number on the prescription is preceded by a (+) sign, then you are generally ‘long-sighted’. It’s an indication of the lens power required, measured in an optical unit called dioptres (D), prescribed to correct our eyes. Glasses prescriptions are written in many different ways.Sphere – The term ‘Sphere’ means that the optical correction required is equal in all meridians (directions). If you have a number in this box it means that you need two types of glasses for distance and reading. As we age, typically around 45 years old, our eyes lose the ability to focus at a reading distance and this number is the amount of correction required to see close up. This number relates to prescriptions which require a reading addition, hence the name ‘add’. This relates to the prism and the position of the lens. Most prescriptions will not have this number. This prism correction will prevent double vision and correct the imbalance. This means that there is a muscle imbalance between your eyes and that they do not work well together as a pair. This number relates to the astigmatism and how much correction is needed in degrees to correct it and will be a number between 1 - 180. This box may be blank on your prescription which means that you have perfectly round shaped eyes. The higher the number, the more irregular the shape of your eye. This refers to a condition called an ‘astigmatism’ and is caused by an irregular, or rugby ball shaped cornea. The number refers to the power of the lens and the higher the number, the stronger the prescription lens is. This indicates if you are long sighted (+) and can see things far away, or short sighted (-) and can see things close up. This box will have a ‘+’ or ‘– ‘symbol before the number. Here are the explanations of the different words and numbers: This image shows the various elements written on an eye prescription and what they mean:īoth of these are the same but are written in 2 different ways: NV - (Near Vision) in place of the ‘ADD’.Sometimes shorthand or abbreviations are used such as: OD - (Oculus Dextrus) for the right eye.OS - (Oculus Sinister) for the left eye.You will sometimes see the Latin terms used for your eyes which are: The unit of measurement for lenses is dioptres.All numbers will be written in 0.25 increments.

#Under cylinder on my glasses script it just says sph. series

The basics of an eye prescription are a series of numbers for your right eye (R), and your left eye (L). You may find boxes on our website that you don’t have on your prescription available but simply ignore them and select not required. Understanding what the numbers mean can help you to input the information correctly, select your lens type and consider the most suitable options.Įntering the information is very easy and is simply a matter of copying the numbers from your prescription into the appropriate boxes. To most people, a prescription is just a series of numbers. You are entitled to a copy of it once you've had your test and should be given a copy without having to ask nor should the optician imply that you have to buy your glasses from them.

You've been to the optician, had your eyes tested and have the prescription in your hand.