For people who work at a computer or at some other mid-length space (like sewing at a machine) these glasses can provide the right type of focus for that length. Because computers are at distance from the eyes further than a book (when reading) this mid-prescription maybe be necessary for some to avoid the strain and weariness that comes from prolonged reading/working at this distance that is too far for reading glasses yet too close for distance glasses. As our population becomes more and more computer focused it is of not surprise that more people would need glasses for this specifically
Well here there are two scenarios,
Your prescription has progressively gotten stronger and you can no longer read with you single vision glasses. In fact anything closer than 18" or so inches becomes hard to decipher. This is very uncomfortable if you read for most of the day, work on the computer, or do some type of sewing/needlework or any such work for any length of the day. You doctor may in fact, suggest computer glasses
that are basically half your regular prescription, which will enable you to comfortable doing this type of work for the better part of the day.
You are on the computer all day long and the eyes are tired, blurry, teary and otherwise uncomfortable. In this case, the doctor may also suggest computer glasses. Some say having a light tint is helpful, others say having UV protection or anti-glare protection added to your lens reduces the glare and thus reduce eye strain.
If you don't need any type of correction, having a tint on non-prescription glasses
maybe the way to go.... Some seem to think so.
Checking with you optometrist or ophthalmologist would be the best way to asses this and deciphering what type of vision correction you may need. Be sure to assess your work space so that you can reliably recount to the vision care specialist, including the type of lighting as well as the various distances of your computer monitor/s.
Remember though that the computer glasses are for closer distances (20"-26"). Blurry eyesight maybe present for longer or closer distances depending on the correction type you need.
Available in computer glasses are:
~ these are the easiest and are basically the vision correction you would need at about 20" to 26" distance. These give the largest field of vision because the whole lenses are used for a single correction value.