Wavefront Simulation using Geometry Optics and Physical Optics

AI Thread Summary
The discussion focuses on simulating the wavefront of laser light (633 nm) through lenses and reflections using geometric optics (GO) and physical optics (PO). Ray tracing is currently employed to track optical path lengths, but concerns about inaccuracies due to diffraction are raised. The need for precision within a micrometer range prompts questions about the discrepancy between GO and PO methods. The governing equations for PO simulations are also queried, especially considering the size of the lenses involved. The conversation highlights the computational challenges of using PO for even small lenses due to significant diffraction effects.
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I am required to simulate the propagation of a the wavefront produced by a laser light (about 633 nm) passing through a system of lens and undergoes a few reflection. What I did at the moment is to do ray tracing, record the optical path length of each ray, then connect every point of the same phase to approximate the wavefront. (The light ray will travel about 1 m)

Clearly, this would introduce some inaccuracy as there are phenomenon like diffraction and etc. I think it will be more accurate to simulate this using physical optics basis, but how good would the improvement be?

More importantly, there are quite some irregular boundaries involve here (lens, for example), which would make the whole computation much more complicated.

1) How can i know the order of discrepancy between geometry optics approximation and physical optics? My application would require error of not more than micrometer range.

2) What are the governing equations should i plan to do the simulation using physical optics?
 
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If the lens is smaller than 0.00633 milimeters then you will have significant diffraction effects and you should use PO or GTD.

I suspect your lenses are much much larger so you should use GO.

A PO integral of 633nm light going through even a small lens would require a lot of computer time.
 
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