I hope I could get good professional advice on choosing the right type of lenses for my case. Recently I had bad experience with local opticians (in Vancouver, Canada). Some of them don't even know refractive index of fancy-name lens they sell :-(
My old glasses that I comfortably wore for six years were:
-4.25 -0.25 135
-4.00 -0.50 067
Lenses: Seiko Ultra 1.60 AS, front surface aspheric, Abbe 42
Frame: full-rim metal 51-16, B 26, pd 62
The new glasses I recently got (after lots of trouble, prescription recheck and return of an improperly made pair):
-4.75 -0.50 135
-4.25 -0.75 063
Lenses: Essilor 1.67 (from Costco), aspheric, Abbe 32
Frame: rimless 52-18, B 30, pd 62
The new glasses definitely give me sharper vision and they look great, but there is a significant "barrel distortion". It is not a problem in the center of view, however the distortion is very noticeable off-center. For example, when I watch large TV, the screen itself is rectangular, but room corners that are about one meter away from TV, look curved (lower parts of walls "bent" towards TV). If I turn my head to put room corner in the center of view, it will "straighten", but then TV would be "bent".
This barrel distortion is not very noticeable outdoors, but it is quite unpleasant indoors, and especially in closed spaces such as small rooms and corridors. I did play with new glasses to see if a change in pantoscopic tilt and/or panoramic angle would make a difference, alas there is no improvement.
At the same time, my old glasses produce only minor barrel distortion (when I use them to watch the same TV or to work in the same room). Therefore, I came to think that the distortion problem is caused by
a) optical qualities of new lenses;
b) higher diopters in my new prescription;
c) new frame that has slightly bigger lens and longer bridge.
From what I've read, to minimize barrel distortion, the following choices could be made:
a) go with a lower index, i.e. 1.60 or 1.53 instead of 1.67;
b) get double aspheric lenses, i.e. where both front and back surfaces are aspheric;
c) select a frame that requires smaller lenses.
I'm considering keeping my current new glasses for outdoor use and getting a second pair just for indoors / computer / TV use. Therefore, I'm not concerned about how this second pair would look, or how thick lenses would be, but I really want to achieve the best optical clarity (while keeping costs reasonable).
So far I'm thinking about the following:
1) Seiko 1.60 DA (double aspheric), based on positive experience with my old glasses.
2) Trivex 1.53, however it seems that Trivex is not available in modern aspheric designs.
3) "Computer lenses" made from CR39, but perhaps they are not for my diopters.
My question is: what material and lens brand would you recommend in my case based on your professional experience?
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