Originally Posted by
Robert Martellaro
Only an A-Scan knows for sure, but usually less for hyperopes, more for myopes. Most of the premium semifinished PAL designs use more or less inset depending on the base curve, ditto for most free-form generated lenses.
I'm curious about your segment decentration strategy by distance power; I decenter myopes strictly by trigonometry, with no concern for prism induced. My thinking is that they've adapted to the base in prism at near, likely for decades, and why make it harder to converge? I'm not looking for looking for trouble, no way no how.
OTOH, hyperopes get base out at near, usually much later in life when they have weaker fusional reserves, with possibly other health and visual disorders. To be sure, increasing the decentration 1mm or 2mm per eye will reduce some of the induced BO prism, sometimes it's best to supply separate SVNO, where the optics can be tailored for the wearer's eyes and Rx, and use the primary multifocals for general purpose wear.
Best regards,
Robert Martellaro
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