Buying Eyeglasses Online
If you want to purchase cheap specs on line then you need to acknowledge a few things first. It is possible to save a vast quantity of cash if you recognise how to purchase your glasses sensibly and it they will be perfectly riskless for you to use as long as you become cognisant of a few simple rules
Ensure that you have the right fit
If your current specs fit right, then take your time in measuring your old glasses and you will need to receive perfectly fitting new specs online.
You need to recognise four measurements:
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Of these the most important measurement is the total width (A). To ensure that your new on-line glasses 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 exact lens prescription
There are a few parameters of your eye prescription that you will need to glean:
- Sphere – This refers to how short or long sighted you are. This value specifies the optical power of a lens in diopters. It invariably has a addition (+) or a subtraction (-) sign 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 refers to the degree of astigmatism that you possess. Once Again, there is always a plus (+) or minus (-) sign around. You don’t always have this value denoted in a lens prescription.
- Pupillary Distance (PD) – This is a really important factor of your prescription which helps to centre the lenses to your face. Technically, PD is the measurement of the distance between the centre of your pupils.
