Coat.exe

[Probeman]

Coat.exe is a very small, simple utility that can be useful for calculating the length of wire necessary for evaporating a specific thickness on your specimen.

A screen shot with the default parameters is shown here:



The other feature in this app is a simple model for calculating the interference colors that produce birefringence as seen here, might be useful for teaching?

[Probeman]

Some of you may have already seen the birefringence simulation in the Coat.exe application that comes with CalcZAF:



Maybe you've also seen the recent Veritasium video on YouTube where Derek explains the rainbow effect in detail. Let's just say I learned something!

https://www.youtube.com/watch?v=24GfgNtnjXc&ab_channel=Veritasium

But something caught my eye part way through the video where he mentions "supernummerary" rainbows, as shown here:



A supernumerary rainbow is created by multiple internal reflections inside a raindrop.  While the birefringence effect is created by just a single internal reflection inside the thin section.

See this time stamp for more details:

https://youtu.be/24GfgNtnjXc?t=1240

But they do appear to be somewhat similar. What do you all think?