Its always interesting how optics manufacturers come up with these terms. I'm an electrical engineer & have had a lot of involvement with electrical manufacturing & the related physics of various processes. A dielectric is an insulator & has nothing to do with optics. I suppose they coined the term because of some process where they use a electric field to apply some sort of coating. Its like cryogenics being used by Leupold for some parts of their scopes. Use a large enough engineering term & users are impressed. State any numerical result past 3 decimal points & its believed. I am 99.275% correct most of the time.
