If you want to purchase discount spectacles on line then make sure you understand one or two essentials before you start. You can save a HUGE amount of money if you recognise how to purchase your eyeglasses wisely and it they will be perfectly safe for you to utilize so long as you become heedful of a few simple rules
Make sure that they fit you properly
If your current spectacles fit fine, then just measure them up properly and you must have perfectly fitting new eyeglasses online.
You need to know 4 measurements:
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Of these the most important measurement is the total width (A). To ensure that your new on-line specs are a good fit for your face, you only really need your total width. Don’t worry too much if you haven’t got your lens dimensions.
Ensure that you have the correct lens prescription
There are four parameters of your eye prescription that you will need to make a note of:
- Sphere - This refers to how short or long sighted you are. It is a measure of your lens optical power and is measured in diopters. It invariably has a addition (+) or a minus (-) symbol in front or above it.
- Axis - this relates to the reference point which denotes the direction of the power of your lens. It only really applies if you have cylindrical lens though.. The value will be a number between 1 and 180.
- Cylinder - This is the measure for astigmatism. Once Again, there is always a plus (+) or minus (-) sign present. There may not be a value of cylinder in your prescription.
- Pupillary Distance (PD) - This part of your prescription helps to centre the lens within your frame on your face. Technically, PD is the measurement of the distance between the centre of your pupils.