On Sun, 17 Jul 2005 21:37:50 -0700, Richard Clark
wrote:
there are questions remaining that
relate to the point of this origin in "Glare." I notice that this too
draws a vacuum of response and yet it was so central to "illustrating"
a thesis.
Dear Readers,
Taking a deep breath and wading into the hits found at Google comes
one very typical observation:
" The methods discussed above will work with varying degrees of
success, depending on the details of the manufacturer's process.
The glare reduction factors claimed by many manufacturers should
not be taken too seriously. Some claim glare reduction factors of
up to 250 to 1. Such numbers are either dreamed up in the
advertising department or are the result of unrealistic test
conditions. A good quality anti-glare filter with a multi-layer
optical coating will reduce glare and reflections by about a
factor of 20. Visually compare glare reductions before you buy
anything."
I leave the WHO undisclosed (being it is such a tantalizing overture
to yet another, unanswerable question). We may all note that what is
described here is "multi-layer" which suggests more than one layer for
more than one BW of glare components (yet another tantalizing,
unanswerable question: What wavelength is Glare?). I will pose that
the necessity for multiple layers is derived from the same need for
one (which is actually quite useless in ordinary life).
As I offered, this is all a very common arena for the optical
engineer, and thin-films are tools for SPECIFIC needs (the WHEREFOR,
or yet another tantalizing, unanswerable question whose origin is one
of practicality) rather than as sacred cows for the theory of
moonbeams.
There are correlatives in RF and antennas such that this is not an
alien discussion. However, it takes little more effort to be correct
instead of simply clowning through the math, because these side-show
results we have been subjected with can be stretched to cover any kind
of bizarre theory. As the final line of the quote above suggests:
"Visually compare glare reductions before you buy anything."
rather ordinary advice that is so aggressively shunned by, instead,
shoveling formulas at us instead.
73's
Richard Clark, KB7QHC
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