U¿ytkownik "Szczepan Bia³ek" napisa³ w wiadomo¶ci
...


Raman discovered that some substances can rework one frequency into many
(also in higher).
May be that a cotton screan also rework.

Next Dr. wrote:
" This is a subject I have considerable experience in. My group at Eastman
developed a process Raman spectrometer that used communications grade
fibers to transmit both the excitation wavelength and the anti-Stokes
Raman scattered light. Chalcogenide fibers, at around $1K per foot, would
be needed to transmit the IR wavelengths needed for the analysis we were
doing. The communication grade fibers cost less than one foot of the
expensive fibers for the entire several hundred feet needed to separate
the analyzer from the chemical process. Our patents were eventually
licensed to the Rosemount division of Emerson Electric.

Raman spectroscopy is based on the _non-linear_ (inelastic) scattering of
photons. It is quite weak; more than 100 million photons are reflected by
the linear (elastic) Rayleigh scattering for every photon reflected by
Raman scattering.

For this reason it was observed very late (1928). It is seen on the film
after many hours of continued radiation.

I am convinced now that Szczepan Bialek is nothing more than an offensive
troll. It is best to ignore him as the physics newsgroups seem to have
done. May he bask in his own stupidity! Or perhaps he and Art and the
gays and the gay bashers could form their own "alt.troll" newsgroup.

YOU ALL make me troll. For my simple question, instead of answers, you send
questions. "Why you want to know?", "Why you write here?". I simply try to
be polite and I write.
You was the first who wrote ( in the answer in my topic): "Nowhere in all of
the respected literature will you find frequency
doubling caused by the two ends of a dipole."
Till now nobody answered me why the polarisation of radio waves disappear
after long way.
Only Richard wrote that the term "polarisation" apply to an equipment. To
waves rather "polarity".
Too late for me for study. "Trolling" is more efficient. About the frequency
multiplying now I know eneugh.
About light polarisation not all. The radio waves and the apparatus are
large enough to observe this phenomenon. The Hertz apparatus is the best for
it. Of course the emitter only. To analise the waves is necessary more
sophisticated than the ring.
S*





In the case of a TV screen, you're seeing either:

- The mixed emissions of a set of red, green, and blue phosphors,
individually excited by electron beams [for CRT displays], or

- The emission from the phosphors of a cold-cathode fluorescent
backlighting lamp (a complex spectrum with multiple peaks) filtered
through red, green, and blue pixel-sized filters (for most LCD
tubes).

In traditional film cinema, you're seeing the emissions of an
incandescent or halogen bulb (fairly continuous spectrum) filtered
through three colors of dye in the film print.

The fact that these complex mixtures of overlapping color spectra can
look "pure white" to our eyes, is due in large part to our complex
nervous systems. Our eye/brain systems adapt to the mix of colors
present under differnet lighting conditions, and interpret different
combinations as "pure white" depending on what's available at the time.

Yes. But for me is interesting the phenomenon at reflecting, scatering and
refraction. May be that "polarisation" is an effect of that.

This is why, for example, indoor fluorescent lighting can actually
look half-decent to our eyes once we get used to it (we "see" a fairly
complete range of colors there) but what looks "white" to use under
fluorescents will actually have a distinctly greenish cast to a film
or digital camera.

It's also why a rather curious phenomenon can be demonstrated. The
*exact* same mix of color emissions may look very different to us,
under different ambient lighting conditions... what might look
greenish outdoors will look pure white or even slightly pinkish under
indoor fluorescent lighting, because our brains *interpret* that input
differently due to the different surroundings.

Is the light polarisation the hard prove that light vaves are transversal?
S*



--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!