I was wondering if this new change for 2010 really is that big of deal.. What is Dielectric Prism Coatings??


Saw it on these binoculars: Nikon Monarch III ATB Waterpfoof 10x42 Binocular Model 7295

Prisms in roof binoculars require a mirror coating to properly reflect light in its passage through the prism. Typically those mirrors have been aluminium or silver based coatings.

Dielectric are new coatings applied as a one molecule deep coating at a time. This process allows a designer a lot of latitude in making mirror coatings perform the way they want them to perform. The coatings can be applied in any number, composition, or sequence to accomplish design goals. The process is typically a brighter image and boosts light transmission a little.

EDIT: The process was initially exclusive to the high end expensive binoculars. It is now to the point where the technology is becoming easier to do, less expensive, and you are starting to see it in more mid range glass. The ZEN ED 2 is the first I am aware of. We are now seeing it in the Nikon Monarch and I suspect the new Vortex Viper line, among others, will have it too.

It should be noted that just because a bino has dielectric coatings it isn't autmoatically superior to one that doesn't. I would take a nikon premier (silver coatings) over a monarch with dielectric

It will however mean that a dielectric coated glass will have have higher light transmission and be brighter than its non dielectric counterpart in the similar quality/price range. I would suspect the dielectric Monarch is better than the original. That is likely to remain a suspicion as my original Monarch never gets used anymore and its dielectric counterpart rings no particular bells. I will take a look if I'm ever anyplace that has one of the new dielectrics. All sorts of differences in binocular technologies are rapidly narrowing. The soon to be increased availability of dielectric coatings is just another example.

The difference may be marginal in any price class and the difference, if significant, is largely "in the eye of the beholder". You may well need to have one of each side by side to see any difference.

there are at least two articles written on the homepage of this site, at least one of which talks about roof prisms and coatings.

Thanks, Optics technology keeps improving.. Has anyone tried these Sightron S111 LR 10x42 Binoculars yet? I see they are plenty heavy in 10 x 42 ..Over 31 ozs..

I sampled a pair of Zen-Ray summit 10x42 binoculars, which also has dielectric prism coating. To my eyes, it is noticeably brighter than the non-dielectric old Monarch binoculars. Is it due to dielectric or overall optical improvement?

The new ZRS ia a new design from the older ones, so I think the answer to your question is ...both. Coatings in general are getting better too. I would concur that my new ZRS is better than my old Monarch.

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.

Actually, the phrase "dielectric coatings" has a very specific meaning in this case ans has little to do with marketing.

Traditional reflective coatings used on the roof prisms (one of the surfaces, to be exact), were made of metal: either aluminum or silver. Newer multilayer coatings are typically made out of multiple alternating layers of two (or more depending on the purpose) dielectric materials. The specific materials vary, but typically these are various metal oxides and salts like TiO2, MgF2, CaF and various vanadium oxides among others. These materials are dielectrics and the original term was used to differentiate them from older style deposited metal coatings.

Also, to address a comment from somewhere earlier in the thread, Vortex Viper and Razor binoculars switched to dielectric coatings a bit over a year ago, I think.

ILya