OD -8.25 -4.50 x090
OS -6.50 -7.25 x080
ADD +2.25 O.U.
He wears GP lenses right now.
His last pair of glasses were bifocals, He told me that's what he wants to stay in.
OD -8.25 -4.50 x090
OS -6.50 -7.25 x080
ADD +2.25 O.U.
He wears GP lenses right now.
His last pair of glasses were bifocals, He told me that's what he wants to stay in.
Were his GP's bifocal, or progressive, or trifocal?
As to options, if patient is retired, doesn't use a computer you might get by with a bifocal. Otherwise use a trifocal. You could also tri a progressive but you would more likely to step in a pile with progressive if has been happy with bifocals.
Chip
you could try 1.74 HI...it will make the lenses much thinner, just be sure to add a good AR coating those lenses will be flatter than a squirrel on the highway and will reflect enough light to blind oncoming traffic! just try to be sure he doesn't try to get one of those aviator size frames, smaller frame means thinner looking lenses, and keeps the "fishbowl" complaint down.
equal opportunity offender!!
1.6 index, abbe 42...
all the way.
Barry,
just curious why would 1.6 with an abbe of 42 be better than 1.74 with an abbe of 33? gonna pick your brain a little!
equal opportunity offender!!
I'll step in here, the ABBE difference is pretty noticeable in powers like that. There is also a 1.70 index with an ABBE of 36 to be considered. But with a low-ABBE lens in that power the off-axis viewing will be compromised by the rainbow effect you get with a low ABBE material. I don't have any problem with it in lower powers, but when I was a -15, you could REALLY tell the difference. I was totally unable to wear 1.67, but could wear 1.70, even though there was still a large amount of peripheral blur and color smear. For me, at least, it was the difference between an unwearable pair and one I could wear.
What the world really needs ia a 1.8 index resin with an ABBE of 40 to make a perfect lens for the high powers, plus and minus.
DragonlensmanWV N.A.O.L.
"There is nothing patriotic about hating your government or pretending you can hate your government but love your country."
In France, you will not find 1,74 glasses with such a cylinder (-7,25).
About a 1,8 index with an Abbe of 40, we can ever dream !!!
And you could charge a fortune for it.
Wesley S. Scott, MBA, MIS, ABOM, NCLE-AC, LDO - SC & GA
“As our circle of knowledge expands, so does the circumference of darkness surrounding it.” -Albert Einstein
Using the Opticampus calculator and assuming a 1.5 CT PD 63/60 Safilo 4119 oval 44/21-
1.6 MR-8 8.1mm
1.67 MR-10 7.3mm
1.70 6.9mm
1.74 6.6mm
Due to ABBE I'd go with Barry's suggestion of 1.6 with of course AR and a light roll.
How long were the GP's out before the refraction was done?
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