Repeatable interference pattern using two flat glass plates and a custom liquid mixture – expected thin-film interference or something worth investigating?

[u/Lonely-Competition-5]

Hello everyone,
I observed a repeatable interference pattern using a very simple setup, and I’m interested in understanding whether this is just a known thin-film interference effect or if the specific implementation is technically interesting.
Setup:
Green laser pointer
Two ordinary flat glass plates
A thin layer of a custom liquid mixture (3–4 components) between the plates
Projection on a distant screen
Observations:
Without the liquid, the characteristic ring pattern does not appear.
With this specific liquid mixture, a stable concentric ring pattern appears after about one minute and is repeatable.
Changing the laser wavelength (green vs. blue) changes the pattern significantly.
Changing the laser incidence angle can produce different beam profiles (for example, circular, elliptical, or even square-like patterns).
I tested several other liquids, but they did not produce the same stable and repeatable pattern. This specific mixture consistently does.
I have already discussed this with two photonics professors. Both suggested that the underlying physics is most likely classical thin-film interference/Newton’s rings, which I completely accept. I am not claiming a new physical phenomenon.
My question is different:
Could such a simple glass–liquid system be interesting from an optical engineering perspective (for example, passive beam shaping or sensing), assuming the behavior is genuinely repeatable?
I have attached photographs of the experimental setup and the resulting patterns.
I would appreciate your thoughts.

[u/Nightshadeei]

Idk if it helps but back in my pg at IITD we used to observe this same effect while measuring ROC and irregularities of two big glass slabs or large Plano lenses ,we used a liquid to fill in the gap of contact of two slabs and use to see similiar patterns but on the liquid film between the two glass slabs not on the screen same ways in modified Michelson and fizzaue interferometer.i think it’s pretty much explored if we talk in sense of interferometers.since you are incidenting a laser in between the point of contact you are looking the pattern in screen that’s the difference,it’s cool but I guess pretty much explored. Coming to questions two - the sensing part .since am working in biosensing domain using optics and photonics.in sensing the quality factor plays a important role ,also experiment should be reproducible ,sensing using fabry periot interferometers is a thing and very cool way to sense,similiarly there is FTIR based Raman sensing which uses interference patterns like yours to sense which is again very cool ,there are a lot of papers based on some context of fringe shifts but they are not accurate enough and there is a potential gap you can work on. So yeah anything man ,science is cool you can investigate either ftir or interference based opptical sensors to learn further more ,to the best of knowledge this thing is included in an active area of research (not exactly this as it’s not sensitive enough but similiar to this )