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Why we need reading glasses ?
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| When we are young everything is always in focus. That is because our eyes have an autofocus mechanism. Just as a video camera constantly refocuses itself as we point it at different objects near and far our eyes are doing the same unknown to us. The lens inside our eye constantly changes shape so that the image we see is in focus all the time. But when we get into our forties this mechanism begins to fail. We begin to have to hold objects further away because the lens cannot focus them if they are too close. Eventually we lose all autofocus ability and have to rely on glasses to see objects that are within arms length clearly. This is normal aging it is not a disease. The medical term for this normal process is Presbyopia. Ophthalmologists are constantly seeking a solution to this but we are a long way off finding it. |
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| As our autofocus mechanism begins to weaken, usually during our forties we find that we need some weak reading glasses to help with close work. At first we can see well with a +1.0 or a +1.25. These will allow us to read newspapers, thread needles, change a plug and so on. As time goes by and we reach our early fifties the autofocus mechanism has almost completely ceased to function and we need stronger and stronger readers. By our mid-fifties most people require approximately +2.0 or +2.5. Eventually by the time we reach our sixties we may need even stronger readers. |
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| Not all people experience the same decline in their reading. Some need glasses earlier or later. Some need a different strength than their age would suggest. Some have and ordinary pair for reading and a stronger pair for a special hobby or task such as watch making or detailed embroidery. We are all different. Choosing the right pair is easy, see our How to Choose the Right Strength section. |
