On Sat, 16 Jul 2005 22:00:47 -0500, Cecil Moore
wrote:
Most of the reflection examples in _Optics_, by Hecht
Dear Readers, it isn't midnight and there is no chance that our
scribbler has actually had the experience to express any solution
bearing on power but his own cooked theory. After-all if we can see
the reflections from these anti-reflective layers, and that is
sufficient proof to invalidate this folderol; well, experience must be
a lie compared to tarted up references (which is so much sacred
hamburger).
So, for the sake of those following this (and sufficiently wise enough
not to jump into this sewer without a snorkel), I posed a simple
question as to the amount of power in the 555nM band (within a 30nM
BW) given a known power of 64microWatts illuminating a square cM
target. I further asked that this be expressed in Lux.
Well, this problem is no more difficult than being able to simply take
the one power already known, the characteristic of a tungsten lamp and
transforming it into the other wavelength. This is a commonplace of
optical engineering unknown to the binary engineer who finds the sum
total of his entire instruction in two pages xeroxed from a library
book.
I will skip the expression in Lux simply because that would be showing
off, and cut to the chase of power expressed in conventional terms
(the binary engineer will be wholly lost in the arcana of practical
measures of light and couldn't be trusted to answer if any power were
actually visible - commonplace experience is a mystery) = 220 nW.
This answer reveals there is more to the characteristic of the
tungsten lamp, than meets the eye. 220 nW is actually quite bright,
and yet we are being handed sloppy work that is acknowledged to
dismiss nearly a thousand times as much power as a trivial difference
that doesn't invalidate a claim of "total" cancellation. I wouldn't
trust such a personality as a bank teller, nor a goldsmith, nor a
surgeon, bridge builder, ... in short, no one serious about the
subject. This kind of slop is what CFA and EH antennas are built
from.
So, this practiced optical engineer has delivered what the binary
engineer could not. Nothing amazing about that - experience clearly
differentiates knowledge from wishing. I could continue with turning
this into Lux/Lumens/Foot-Candles/Candelas (terms of confusion to our
scribbler), shifting the wavelength again, expressing the total power
radiated, expressing the total light seen (or power in the BW selected
light), and so on that are complete mysteries that utterly wipe out
these facades breathlessly offered as compelling proofs.
The single most embarrassing question I've offered to this correlation
of "glare-proof" optics was to ask the obvious:
What wavelength is Glare?
Even here there is a practical answer that stumps the binary mentality
limited by the lack of experience, and the dearth of exposition from
two pages of thumb worn xeroxes.
So, we have these "Can you solve this?" howlers where the author is so
utterly unversed on the topic that he cannot describe power; fails to
acknowledge if that glare's reflection could be seen at the typical
values found in perfect math solutions; what wavelength we are talking
about; why the problem is posed out to 5 places of precision and with
only 1 place of accuracy results; why a light level of 1/1000th of the
typical perfect math solution is still visible but is dismissed as a
correct result.
It has been amusing nonetheless.
73's
Richard Clark, KB7QHC
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