> If anyone wants to challenge the above, work out the size of the Airy
> disk at different frequencies. :-)
Hi David,
This is the first time I have heard the term "Airy disc" used in the contex=
t of acoustics.
For a parabolic dish, while the theoretical focus is a non-dimensional poin=
t, in practice it will be distorted over a measurable volume of space. From=
my perspective this practical "focus" will likely be a non-uniform, asymme=
trical blob rather than a sphere or disc. This focal blob could be looked a=
t as a disc by taking an average radius at a cross section. Is that close t=
o what you mean by Airy disc?
John Hartog
rockscallop.org
"While a picture is worth a thousand words, a
sound is worth a thousand pictures." R. Murray Schafer via Bernie Krause.
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