Two random questions (ELI5)
1) At LensCrafters when a person picks out a large frame, an aviator for example, and cutout won't accommodate the 70mm finished lens, they would place the OC wherever necessary to make it work. Is this typical practice for large frames? If prism is prescribed to "pull" a lazy eye, wouldn't unprescribed prism be harmful? Or at the very least make it more difficult to see as the prescription gets stronger?
2) LensCrafters also does personalized progressive lenses (vertex distance, frame wrap, ect) so you get like -1.46 Sphere Power + 2.47 Add power, but they didn't do it for single vision. Do any places do this for single vision? And if not i assume there's a reason? Is it because most optometrists only measure in quarter diopters anyway so going from -2 to -1.95 could actually be worse because you were measured at -2.08 which was rounded down to -2? But once you get up to a higher RX like -7 it seems like where the lens sits would be a lot more significant and this would be viable.
Prism in Sunglasses and Personalized Lenses? Two Random Questions
1) At LensCrafters when a person picks out a large frame, an aviator for example, and cutout won't accommodate the 70mm finished lens, they would place the OC wherever necessary to make it work. Is this typical practice for large frames? If prism is prescribed to "pull" a lazy eye, wouldn't unprescribed prism be harmful? Or at the very least make it more difficult to see as the prescription gets stronger?
2) LensCrafters also does personalized progressive lenses (vertex distance, frame wrap, ect) so you get like -1.46 Sphere Power + 2.47 Add power, but they didn't do it for single vision. Do any places do this for single vision? And if not i assume there's a reason? Is it because most optometrists only measure in quarter diopters anyway so going from -2 to -1.95 could actually be worse because you were measured at -2.08 which was rounded down to -2? But once you get up to a higher RX like -7 it seems like where the lens sits would be a lot more significant and this would be viable.
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