Here's my prescription:
OD: sphere - 4.25, cyl -1.00
OS: sphere -8.50, cyl -0.75
Due to the vast spherical difference, the OS lens would inevitably be much thicker than OD were lenses of the same refractive index used. I'd like to know if there are any cons to mixing different indices for each eye. Let's say, using lens with index 1.61 for OD and 1.70 for OS, so the difference in thickness between the two lenses is smaller, resulting in better cosmetic outcome and better weight balance.
I am aware that the Abbe value for 1.70 is likely lower than that for 1.61, thereby resulting in worse chromatic aberration for the former. Does this translate into any negative effects to my eyes' health or vision, or to the way my brain processes visual signals from the eyes? For example, would I be more prone to dizziness because light is refracted differently for each eye?
Added (1). Assume that the two lenses are of the same brand category made by the same company, and made of the same material (hi-index plastic). They are both aspherical or bi-aspherical.
См. статью: What are the downsides of mixing refractive indices for eye glasses lenses?