I've been hearing from colleagues in Europe about the new Zeiss Gradal INDIVIDUAL progressive lens.
Seemingly each lens is custom designed, similar to Rodenstock's Multigressive, and apparently when ordering, the lab needs to know, not only the Rx and individual heights and centres, but also the vertex distance and pantoscopic angle of the frame relating to the face, all this is taken into account in the design of the progressive power surface.
Has anyone had any experience with this lens yet?
No, I haven't any experience w/individual. But, I spoke with teh ZEISS reps from germany at VE east, and asked just how we were going to measure the pantoscopic tilt., i.e., relative to what reference point?
His answer was vague, and revealed to me that this is more a marketing point than a real tangible benefit.
Maybe refractionsists do a better job in Europe? I can only hope so.
Why compensate for pantoscopic tilt when, here in the US, we do not even know if the refraction is for full distance correction, replete with the smallest amounts of astigmatism corrected.
btw...
20/20 uses a 20 foot reference distance
20 feet = 6.1 meters
6.1 meters = 0.16 diopters
Does this mean all RXs done at the 20 feet exam distance are undercorrected by more than the ansi tolerance for the majority of sphere powers?
Why bother with pantoscopic tilt, I ask?
Barry Santini
ABOM
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I think the man who said "the customer is always right" was only interested in profits, and not the TRUTH
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