I need a new pair of spectacles, so went to my optician. Among other things we discussed was the availability of Lotutec coating on my new glasses. He then said that Lotutec was only available on synthetic lenses not on glass ones. And the reason according to him was that Lotutec would not hold on glass. So his implication, then, was that binoculars and scopes with Lotutec coating would have synthetic lenses, at least the ones on the outside. I think all this is not true, but just to be sure, I post it here for opinions. My own thinking goes into another direction: Manufacturers are pushing synthetic lenses for two reasons:
1 they are lighter in weight and thus more popular, and
2 they are being scratched more easily and thus need faster replacement. Which suits the manufacturers.
Thus, along this line, then, Lotutec is not being offered on glass because the demand is lower. I infer this from my other problem: I don't like variable focus glass in my spectacles. Thus, I use trifocals much to my satisfaction. However, these are becoming less and less available. I.e. there is a limited availability of options, like glass or synthetic, self-darkening or not. And in particular, Zeiss is the one company that has cut down on these options.
Robert,
Nikon "W" 1.74 high index trifocals are almost half the thickness of my last pair.
If you have a pair made up as sunglasses, the 1.67's can be dry tinted to a 75% brown, which cuts down blue light transmission, thought to contribute to acute macular degeneration in folks who sunburn easily.
Mike
[QUOTE=Mike Penfold;990087]Robert,
Nikon "W" 1.74 high index trifocals are almost half the thickness of my last pair.
If you have a pair made up as sunglasses, the 1.67's can be dry tinted to a 75% brown, which cuts down blue light transmission, thought to contribute to acute macular degeneration in folks who sunburn easily.
Mike[/QUOTE]
The type I have now ordered has self-staining glass. I very much like this type of glass. Fortunately, my optician found a supplier after doing some searching. After a while (several years), the staining is no longer fully reversible. But the residual coloring is no real problem. It even helps reduce some glare while driving, as the color change does not work behind UV filtering glass of the car.