On Wed, 03 Aug 2005 11:54:08 -0700, Jim Kelley
wrote:

I have, by the way, found similar
but less detailed drawings of thin film interfaces in two different
physics textbooks. I think the key to understanding them is the
superposition of multiple reflections.

Hi Jim,

Such coverage as you describe, in physics textbooks, are rudimentary
discussions suitable for introductory purposes. They are not the
end-all be-all nor final word on the matter. This is born out by
exhausting work being pursued by many in academia and the industry to
"completely cancel" reflections. They would not be so engaged in this
work if a simple, quarterwave, thin layer optic performed this
complete cancellation already. The fact of the matter is that by the
mechanics so described in the text books, they guarantee no totality
of cancellation. True, they offer a close hit, but this is not proof
of totality. Close is good enough for nuclear hand grenades too.

When the energy available in the first medium, at the second
interface, cannot possibly reflect enough of it to the first
interface; then no amount of superposition of ALL reflections (and
this presumes that the second interface is fully reflecting for these
succeeding multiples, an absurd notion in its own right) can exceed
that available energy.

Yes, this has all been said before, you've found it interesting but
not compelling; and yet no one here has offered any way to boost the
energy to completely cancel the reflection from the first interface.

Under the circumstances already described, those reflection products
(after assuming ALL the multiple reflections have been ushered out
from behind the first interface to destructively interfere) contain:
1800 TIMES MORE POWER THAN THE SUN!
which has been humorously relegated to zero. :-)

Flowing, dribbling, puddling, or simply expressed in terms of candelas
per square foot per fortnight, it all leads to the same conclusion:
the cancellation is not total. Hence the subject line of
The Extreme Failure of Poor Concepts
in Discussing Thin Layer Reflections

********* for those who cannot cope with the topic *************

I have a D Cell battery whose capacity is 3 W-HR, and I roll it along
the floor.

Has power flowed?

How much? (sorry if I offended anyone by asking for a quantitative
answer)

73's
Richard Clark, KB7QHC