What would be the best high index glasses for a very high prescription for farsi!
Question: I would like to decrease the "coke bottle" effect as much as I can. Also, how much more does high index cost?
Answers: I would like to decrease the "coke bottle" effect as much as I can. Also, how much more does high index cost?
If you can get high index, go for it. In my case, it reduces the thickness of the lenses in my glasses so it looks like I'm wearing regular glasses, not strong ones. I like that. They are lighter and not as prone to sliding down my nose as regular lenses would be for me.
An optometrist can advise you on this, but can I just correct one thing. The bottom of the coke bottle is actually a minus lens, the opposite shape to the one you are concerned with. For farsightedness a plus lens is prescribed. I'll explain.
A plus lens at it's most basic is shaped like a lentil. Flat on one side and rounded out on the other. Known as convex. This is the reason we got the word "lens" in fact, from the perceived similarity to a lentil.
A very basic minus lens is the opposite. Flat on one side and concave on the other (rounded in). An extreme version is concave on both sides, and that's the base of your Coke bottle.
The confusion between the two is common, but unforgiveable. People don't pay attention, or don't think.
With your high prescription for farsightness. . the higher is it the bigger your eyes are going to look. So get a 1.67 lens and tell them to do the center thickness as thin as possible. Because with your prescription the center of the lens is gonna be the thickest part. Because for people that a nearsighted and have a high prescription the lens is going to be the thickest in the edges. High Index lenses can range from 170 and up.
Because you are farsighted you need convex lenses; the high-index lenses will be "thinner" and lighter for the same power lens. Looking from the side your lenses will be thinner, but looking straight on, your eyes are still going to look big like before, because the lens still needs to be the same power, so the magnification effect will be the same as before. Also, to minimise the thickness/weight try to pick out frames with fairly small, sort of roundish/ovalish shape lens openings, where your eyes line up with the center in the openings of the frame pretty well.
The highest index lens on the market is a 1.74. Show your Rx to an optician that will better be able to assess your situation. The higher the index the higher the price. A 1.74 might be overkill in your situation and a waste of money!
You got some good advice from the other posters...please ask your optician to measure for optical centers. Sometimes the curvature of the lenses may either raise or lower your optical centers making it a little difficult to see. And depending on your Rx, if you are +4.50 or below, I wouldn't do anything higher than a 1.67 index lens.