
Geometrical Optics - peter_d_sherman
https://en.wikipedia.org/wiki/Geometrical_optics
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peter_d_sherman
>"Underlying mathematics

As a mathematical study,

 _geometrical optics_

emerges as a short-wavelength limit for solutions to hyperbolic

 _partial differential equations_."

PDS: Here's a weird question:

Can we get computation via light wavefronts and specifically shaped lenses?

Now, I know about optical computers and how they can implement AND/OR/NOT/etc.
gates via light.

For the purpose of this question, I'm not talking about anything like
traditional logic gates or anything that's boolean in nature...

I've seen mechanical analog computers from a long time ago that used specific-
to-computation 3D shaped objects to either perform calculating derivatives or
differentials (forget which), so I'm wondering if the same effect is possible
using lenses specifically curved for specific calculations, and what those
wavefronts or wave patterns and lenses would look like, if they existed...

In other words, what is computable given any light wave pattern (analog), and
the ability to create any lens design pattern, no matter how strange-looking
or complex?

?

