A question for Opticians

[scoobydooby]

If i've had my eyes tested and my prescription is -0.50 in each eye, is there anything stopping me from purchasing specs which are -0.75 in each lens? My vision used to be better than 20/20 but I needed specs for a few years until I then had Laser correction. After this, my eyesight was better than 20/20 again for several years. My eyesight has now started to deteriorate again (I knew this could happen) and I need to wear specs for driving. However, I want to be able to see more than the legal requirement says I must. I presume with my prescribed specs, my eyesight will be 20/20 vision again? But.......I've experienced better than this and that's ultimately what I'm after. My friend's specs are slightly stronger than mine and I feel as though I should be able to see through mine, what I can through hers. I'm not talking about binocular vision - I just want what I had before. Is there any reason why I shouldn't have glasses that are slightly stronger?

[kempie]

I am not an optician!!!

Firstly, 20/20 (or 6/6 for the acuity scale used in UK) is classed as 'normal' vision but should not be thought of as a standard which is used for anything specific.

When an optician prescribes a lens for your eye it is to attain the "best corrected visual acuity (BCVA)" for that eye and should be the optimal lens i.e. one that will not cause eye-strain etc. with prolonged use. Your BCVA could give you superb 6/4 vision, it could also be a lowly 6/24, but it should be the best corrected vision you can attain without causing pain/damage.

Since lens strengths are graded in 0.25 steps it could be the case that your eyes are somewhere between -0.50 and -0.75 so the jump to -0.75 may be minimal; likewise they could be between -0.50 and -0.25 meaning the jump is far greater and potentially detrimental to your eye health. However I would suggest that the eye specialist who tested your eyes should be the best judge of the correct lenses for you.

Furthermore you mention 'legal requirement' for driving. If you mean a private vehicle then the DVLA requirement is equivalent to about 6/10 (20/30 ish) in both eyes.

[scoobydooby]

Thanks Kempie - I didn't mean to be too specific about the legal requirement for driving, as I don't know what it is......I just used the term 20/20 vision as it's well known and would assume that whenever my eyes are tested, they meet this at least. But I don't understand why they're telling me I'm -0.50 when only something stronger will take my eyesight back to what it was. For example, I used to be able to read a clock on the wall of another office but I no longer can - even with my new specs! Apparently, it's okay because 'most people wouldn't have such good vision anyway'...that's pants.

Anyway, sorry to go on but.....eye strain? What's the worst possible effects of eye strain? Could it make my eyes worse? Headaches maybe?

[kempie]

Symptoms of eye strain can include:

Blurred vision (somewhat ironic)
Headaches
Tiredness
Dry itching or burning eyes

[Teddio]

As you get older the elasticity of your lens decreases and your focal range decreases. Visual acuity is not only dependent on the refractive properties of the lens and cornea but also on the health of the retina.