jennifer wrote: > > I tried them on and > immediately felt dizzy. I could look straight ahead and see clearly, > but any other direction made me feel unsteady and I got a headache > after wearing them around my house for 15 minutes, trying to get used > to them.
Seeing clearly through the middles of the lenses and getting poor visual quality off the lens center is characteristic of a lens material with high chromatic dispersion. Not all lens materials are similar in this regard. If you specified polycarbonate lenses, know that it is probably the worst commonly used lens material in terms of its optical qualities. The best lenses from an optical standpoint are CR-39 plastic and crown glass. They are both fairly low-index materials, though (1.5 and 1.52 respectively), so they make thick glasses. In my experience, they give the best vision of any lenses I have tried. That's too bad for me, because I usually can't make peace with the thick ugly lenses they provide in my strong prescription. Lenses with a high base curve (bulged/bug-eyed) introduce some geometrical distortions that can make switching between different glasses a funhouse-type experience. This is easier to get used to than poor optics, but in my opinion flatter lenses are generally better for seeing. Folks with strong farsightedness may differ. Chalo --~--~---------~--~----~------------~-------~--~----~ Check us out at the oft-updated http://glassyeyes.blogspot.com! You received this message because you are subscribed to the Google Groups "GlassyEyes" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/glassyeyes?hl=en -~----------~----~----~----~------~----~------~--~---
