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From: firstname.lastname@example.org (William J. Beaty)
Subject: Re: Make infrared goggles inexpensively (like $10!!!)
Date: 17 Sep 2002 12:41:46 -0700
References: <email@example.com> <firstname.lastname@example.org>
NNTP-Posting-Date: 17 Sep 2002 19:41:46 GMT
Jonathan Kirwan wrote in message news:...
> On 17 Sep 2002 01:41:17 -0700, email@example.com (William J. Beaty)
> >You seem to be arguing that an optical sensor's frequency
> >response curve cannot be treated the same as an audio sensor's
> >curve. Since when? Unless it comes down to triggered fluorescence
> >effects or rare phenomona such as "squeezed light" noise effects,
> >a frequency response curve is still a frequency response curve.
> >Quantum mechanics doesn't force us to handle an optical frequency
> >response in a different way. (In other words, in the limit of
> >large numbers of interactions, QM becomes classical physics, and
> >optical lowpass filters behave like RF lowpass filters.)
> You are just arguing for arguing's sake, it seems.
LOL! Nope. I was querying for details. You seem confident
that my analogy doesn't apply, which seems very strange to me,
so I'm trying to find out why I'm supposedly wrong.
Is it because you think that 700nM electromagnetic radiation is
quantum mechanical, while 30KHz audio is not? Therefore the
frequency response curve for an audio detector MUST not be an
analogy for the frequency response curve of an optical sensor?
Wrong. Note the word ANALOGY: of course light is not sound!
The situations are **analogous**, not identical. Filters and
sensors for both audio and for optical have analogous behavior.
(I hope you're not arguing that, in order to have an acceptable
analogy, the two situations must be *identical.*)
> Not from really
> understanding this. For now, I just don't have the time to worry
> about it.
So you'll criticize, but when challenged, you quickly back down
while claiming that the challenger doesn't really understand?
Hmmmm, very interesting Dr. Freud.
Actually, seeing your behavior I thought that *you* were attacking
my analogy purely for arguing's sake. There are quite a few
flamers on these particular newsgroups, and they share a pair of
symptoms: a love of criticizing others, and a total inability to
admit to any mistakes of their own.
> >Yes, there ARE some exotic situations where QM makes a difference.
> >But filter response and sensor response curves are not an example.
> I was addressing myself to your example of being able to hear 30kHz if
> the power in that band was strong enough as an explanation as to how
> one might see other wavelengths. There IS a mechanism which can allow
> higher frequencies to generate sufficient travelling waves to be
> detected as sound in the cochlea.
So you're assuming that I was talking about nonlinear effects
in the ear? But you first said that it was QED which made
audio so different than optical. Changing your story?
(Apparantly it doesn't really matter WHY my analogy is wrong...
It's just wrong!)
Re. nonlinear acoustics: no, the thought had never crossed my
mind. I was thinking about a much simpler idea: the frequency
response of a detector has a rolloff rather than an infinitely
steep edge, and if a detector "sees" an out-of-band signal as
being down several orders of magnitude below threshold, we can
just crank up the signal level by several orders of magnitude
and the signal becomes detectable. Or instead just raise the
detector gain by several orders of magnitude by removing the
background noise and letting the detector's AGC crank up its
gain. The audio analogy applies to human IR vision just fine,
and involking QM doesn't change that. Neither does involking
nonlinear effects (and ears sometimes can hear off-band signals
just because the high signal intensity compensates for the ear's
weak response, without nonlinear effects having anything to do
with it.) Maybe you don't like the 30KHz value because it's
too far off-band. I was thinking about little kids who can hear
above 20KHz, so I picked 30. For us old farts, I could pick
15KHz as being "off band." But then someone else would no doubt
attack my reasoning because some people hear 15KHz just fine.
> But that mechanism depends on
> nothing similar to how light interacts in the pigments in cones and
> rods. And the analogy you gave doesn't apply.
> I'm just surprised you could think so.
You're making incorrect assumptions. My reasoning has nothing
to do with standing waves in the cochlea, and everything to do
with the ear's NON SHARP high frequency rolloff. If a signal
is below the detection threshold at the high end, just crank up
the signal amplitude until it's audible again. That, or remove
all the environmental noise so the ear lowers it's detection
threshold. If you don't like the 30KHz value, then let's call
(((((((((((((((((( ( ( ( ( (O) ) ) ) ) )))))))))))))))))))
William J. Beaty SCIENCE HOBBYIST website
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Seattle, WA 206-789-0775 unusual phenomena, tesla coils, weird sci
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