Re: Apollo 11 Experiment Still Going Strong after 35 Years

From: Peter Smith (psmith6_at_SparnBlock.bigpond.net.au)
Date: 07/27/04 

Date: Tue, 27 Jul 2004 12:54:22 GMT

Lou Scheffer <lou@cadence.com> wrote...
<snip>
> To first order, it
> seems a section of a sphere with a corner reflector
> at the geometric center of the sphere would have the
> right properties. - from any angle, the shortest
> path is from the source, just misses the back of the
> corner cube, off the mirror, hit the cube, and
> return. This shortest path is identical for all
> incoming directions, and by symmetry so is the whole
> response.

Because the corner cube array is a surface, it will not all be at the
centre of the sphere (or paraboloid). This would introduce significant
dispersion from most incident angles. As I imagine it, your device would
do what you want only from one precise source angle.

- Peter

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