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cylindrical diagonals?

Started by yahganlang, 07/29/2005 07:52PM
Posted 07/29/2005 07:52PM Opening Post
Hi again. I'm building a binoscope out of two Synta 6" f/8 scopes, and am trying to figure out the best way to bend the light path to severely shorten the overall length. So far I've been hunting around for flats, diagonals, Newtonian secondaries and so on (just got a bunch of inexpensive copier first surface mirrors that probably won't be flat enough).

Anyway, it snapped into my head moments ago as I was reviewing the sketches I have for the design that perhaps one could substitute a cylindrical mirror for two flats perpendicular to each other (causing a 180 light path turn with translation away from the original axis).

The question I have (lacking a ray tracing program) is whether a simple cylindrical unit would suffice here, or would it have to be more like a toroidal mirror, to preserve the trajectories of rays laterally. Just on paper the reflection in the direction of translation away from the original axis looks ok. I have problems with 3D images without having an actual model in front of my face.

Thanks for input.
Jess Tauber
[email protected]
Posted 07/30/2005 03:47AM #1
I think it will be very hard to find cylinderical
mirrors with required accuracy. And I just don't
see any way that is going to ray trace well; there
will be enormous astigmatism.
Posted 08/01/2005 08:12AM #2
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jess tauber said:
...

The question I have (lacking a ray tracing program) is whether a simple cylindrical unit would suffice here, or would it have to be more like a toroidal mirror, to preserve the trajectories of rays laterally. Just on paper the reflection in the direction of translation away from the original axis looks ok. I have problems with 3D images without having an actual model in front of my face.

Thanks for input.
Jess Tauber
[email protected]
[/COLOR]

Jess,

You might try getting some cylinder mirror from Edmund or Thorlabs and do some testing on a small scale.

http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productID=1944&search=1

David Simons