Wednesday, February 10, 2010

The worse your vision, the thicker the glasses lens?is it true?

I'm pretty sure they do get thicker as your vision worsens.The worse your vision, the thicker the glasses lens?is it true?
yes im pretty sureThe worse your vision, the thicker the glasses lens?is it true?
Not necessarily, but in some cases. Very thick glasses are usually needed for cataract surgery without implants, rare today.
True, but not always.





The worse your vision is the greater the correction is required. But, how bad is that vision and what makes it bad.





For example I have a lazy left eye so my right eye could have a thinner lens than that for the left eye. That would unbalance the glasses so both lens are made to weigh the same, but the correction value is different. Furthermore because of the bias the right eye needs addition correct to force it not to offset for the correction to compensate for the lazy left eye.





Now I am getting older and my vision is failing through normal means so I require bifocals; with 4 sets of correction values, two for each lens.





My brother-in-law has thick glasses because he needs more vision correction than I do. The spherical distortion in the cornea needs a thicker lens to make the correction. His vision problems have remained constant for quite a while mine are worsening. Yet he still has thicker glasses than I do. Although overall his vision is better than mine, and his corrected vision is even better since I need to replace my glasses soon. The extra thickness is because the adjustment has to take place over a larger distance. My lenses are thinner because they don't need as thick a correction medium to adjust my vision properly.





Then you can have a difference in the medium, glass is heavier than plastic and you can do more with glass. If you break up the correction as in trifocals or bifocals then the thickness can be decreases since the angle for the correction will be smaller. My brother-in-law needs a larger angle of correction than I do so his glasses are thicker, but my vision is worse than his.
yeah
no not at all if u go to a decent optician they can get ur lenses thinned down for u, the reason i know this is because i get mine thinned every time i get a new pair and im registered blind coz i have seriously bad vision (obviously) and i dont walk around with glasses like the bottoms of milk bottles
Also the more surface area of the lens the thicker. For instance a kids pair of glasses will be smaller than adults glasses of the same correction level
Mostly.


It certainly is true that the higher the Rx numbers, the thicker the lens will be.


There are high index materials which help keep lenses relatively thin, but in any one of these, the worse the Rx, the thicker the lens (In the centre for + lenses, at the edge for - lenses)


But the size of a lens matters a lot too. With a high-powered Rx, the smallest, roundest, frame shape *that suits you* will give the thinnest, best looking, lenses and glasses.





But the answer to your question can be ';false ';.


It is possible to have very bad vision and not need glasses at all. This happens where the problem is retinal damage, amblyopia, cataract... a whole range of eye problems where adding spectacles lenses, thick or not, will not raise the vision. So bad vision, but not thick glasses.





With a longstanding amblyopic eye in an adult there *may* be no point at all in having a thick +5 or worse lens in front of it, but I still see people with this because they always have had it, from early childhood. The cosmetic improvement of swapping it for a ';balance'; lens that looks like the one in the good eye can be massive.





Optometrist, retired.
yes
Yes it's true. There is a type of polycarbonate lenses that are thinner than regular plastic lenses, but worse vision still equals thicker lenses.
Not half as bad as it use to be. Now a days they can make them pretty compact. No more heavy Glass either.
Yes, and I guess this links to your next question.
Im legally blind w/o glasses. My vision is so bad, I cannot see the big ';E'; on the eye chart w/o contacts or glasses. My vision is about 20/200. My glasses are no thicker than my husband who has like 20/40 vision. His contacts are like -1.25 and mine are like -6.75 (yes they go that high). Nevertheless, my lenses are really expensive to get so thin. If I got ';cheap'; lenses they'd be coke bottles!
uh, duh?
Yes, unless you pay loads to have thinner lenses
Not really the case anymore. The thickness of the glass is only a slight factor in today's technology. The way they curve the lense, and where they make the thicker portions are the way they help you see.
Yes.





Long-sighted people have the thickest part of their lens in the middle.





Short-sighted people have the thickest part of their lens on the edges.





Though there is technology that reduces the thickness. I'm wearing them now.
yes thats true b/c the lens needs to be stronger to be more effective
this is true mine are thin but i know alot of people with thick ones and they are blind as hell with out them.
thick lenses are for short sighted people. so i would say true
not nowadays, you can buy an extra package so they slim down the lenses.

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