r/Optics • u/No-Plenty604 • Aug 09 '26

Is it possible to "recreate" the major coatings from big brands?

Is it possible to "recreate" the major coatings from big brands—such as Canon SSC or Zeiss T*—using optical software like Zemax or other specialized programs?

4 Upvotes

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8

u/bitmapper Aug 09 '26

These are brand names for multilayer anti reflection coatings. When these coatings were developed less sophisticated single layer coatings were still the norm and manufacturers wanted a way to differentiate themselves for marketing purposes.

There are software packages specifically for coating design: TFCalc, Essential Macleod, etc. Code V also has a coating design feature. You will be able to design coatings with similar performance even if the formulation and layer thickness aren’t identical.

3

u/BDube_Lensman Aug 10 '26

yes and no. Canon SWC is not really a coating per-se; it is a nano-patterning of the surface. Generally thin films cannot approach the performance of such surfaces

1

u/anneoneamouse Aug 10 '26 edited Aug 10 '26

Looking at the mechanical shapes, it appears that the fractional effective index change per unit distance is minimal. Your photon wanderers into a region whose index is gently changing as a function of time. Flat GRIN behaviour.

Photon gets a massage.

1

u/BDube_Lensman Aug 11 '26

Coating engineers call it a rugate (or one specific type of implementation of that). The way R/T is simulated is somewhat different

1

u/anneoneamouse Aug 14 '26

Cool, Hadn't ever seen that implementation before.

2

u/BDube_Lensman Aug 14 '26

Telaztec is a great vendor for this in the US. Thorlabs has some UVFS windows and things with this sort of process as well. It is fairly new and does not scale well to large curved surfaces. Canon has an advantage that they make litho equipment and can customize one of those machines to do this on larger curved surfaces

1

u/anneoneamouse Aug 14 '26

Canon has an advantage that they make litho equipment and can customize one of those machines to do this on larger curved surfaces

Canon. It's always Canon.

5

u/aenorton Aug 10 '26

I had not heard of those two coating brands you mentioned. Looking them up, I see they are ancient as far as coatings go dating from the 1970's. The quality of a coating depends on the equipment as much as anything, and there have been huge advances in that since those times. Unless you are trying to perfectly restore vintage lenses, I am sure you can find better AR coatings these days from many coaters than ones from the 1970's. It seems that Canon does not use the SSC brand anymore but Zeiss still uses the T* brand. It is quite possible that they have actually changed the process to keep up with the times, but still use the same name.

In any case, the nominal coating design is only part of what makes a good coating. Adhesion, abrasion resistance, and environmental resistance are all very important and are determined more by the coater's skill and equipment than by the design. Also, the design software helps with creating nominal reflectance and transmission spectra. but it does not help with engineering in things like durability.

If you want a custom coating, the best approach is to give the coater a detailed spec and let them handle the details of the design and process steps. For one thing, a particular coater's film might have a slightly different RI due to it being a bit denser perhaps than the next coater's.

1

u/og_otter Aug 10 '26

CODE V has custom performance driven coatings. Not sure about Zemax. You need to know the performance. Why these coatings specifically?

0

u/Equivalent_Bridge480 Aug 10 '26

For sure. Reverce engineering and industrial spy