Parallel light rays through a sprial wave plate diverge?

AI Thread Summary
Parallel light rays do diverge slightly upon exiting a spiral wave plate, which raises questions about the angular momentum of the light. The discussion critiques the assumption that light would behave in a straightforward manner without any interfaces, suggesting that the expected outcome should be a straight beam. Observations indicate that the symmetry of the spiral wave plate leads to a more complex interaction than initially thought. Critics argue that despite the potential for light bending, the overall behavior remains consistent with expectations for homogeneous materials. The conversation emphasizes the need for further exploration into the implications of these findings.
Spinnor
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Do parallel light rays diverge if ever so slightly upon exiting a spiral wave plate? See image below.

phase-plate.jpg


450px-Spiral-phase-plate.png


Images from,

https://www.google.com/search?q=spiral+phase+plate&safe=off&sa=X&es_sm=122&biw=1360&bih=649&tbm=isch&tbo=u&source=univ&ei=xEGDVcaKFYLV-AHZop_IAw&ved=0CC0QsAQ#imgrc=V_wYVTQHs9_JcM%3A;MIMazroQRD_VYM;http%3A%2F%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2F1%2F1f%2FSpiral-phase-plate.png;http%3A%2F%2Fen.wikipedia.org%2Fwiki%2FAngular_momentum_of_light;1047;382

If there is divergence does that change the angular mementum of the light?

Thanks for any help!
 
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If there is no interface between those glas parts where would you expect any special things but a straight beam?
It makes no sense from the very beginning.
 
Omega0 said:
If there is no interface between those glas parts where would you expect any special things but a straight beam?
It makes no sense from the very beginning.

The first image above seems to show a typical light ray bending.
 
Spinnor said:
The first image above seems to show a typical light ray bending.
Come on... the symmetry is circular and waves here are as I expect them...it seems to be homogenieous material ... you can find silly ways to bend light but in the end you will have nothing but light, may be polarized. From symmetry reasons the outcouming is nonsense. If it is homgeneous stuff.
May be harsh critics but I think Spinnor will report about it.
 
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