Re: [ATM] The standard aluminium coating: How much scatter?

[Andy Saulietis <iss@pvtnetworks.net>]

Scatter

I once had the opportunity to examine an aluminized but not overcoated
mirror with a scanning electron microscope. The surface appeared like
a cobblestone street, with facets of various numbers of sides. The tops of
the facets were convex, with a curvature about 1/10 the width of the facet.
The facets were a few angstroms in size, so should not contribute much
scatter unless they were regularly spaced, so they could possibly act 
like a reflective
diffraction grating. This was just one sample, not from a telescope mirror.






Andy Saulietis
ISS Enterprises
10 Milky Way
Mayhill NM 88339


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