On the basis of a project at the university I made some spectral
analyses at a fluorescent lamps. But now I have some problems with the
analysis of me measuring. The analyse takes place in tha matlab
First of all I have used three different kind of lamps which where
produced in different way.
At pictures, made by a digital camera we seems that there are two
hotspots, i,e the hottest point of the electrode which is glowing was
not on the emitter material, but on the connection between the leg and
the wire and also outside of the leg. What can be the reason for this
Also in this case was no hot spot to see during the cathode face. Then
you do not see the red glowing point, but it is completly dark.
Then it is obvious that the lamps with the two hotspots reach a much
higher intensity, i.e there is a higher temperature. Does it mean,
that the emitter material is faster consumed?
There you can also see that the highest intensity occurs in another
area of the filament.
But hte most interesting thing is, the lines we can see from our
The mercury line we can identify without any problems because we know
exaclty there position. But in additional we see two more lines with
the wavelenght of ~ 558 and ~ 589 nm. I guess it is Krypton but I am
not sure. What does it tell me when I see Krypton?
When I look to the measurements, it seems to me that all the major
lines are coming either from the mercury or the krypton. Argon can be
seen but is masked by the lines from mercury, it probably appears as a
noisy line spectrum in the red part of the spectrum.
But still there is one more line and this is not identified (I see it
a white arrow) and has a strange behaviour:
identified lines seem to "come from the discharge" during the anode
phase and "come from the electrode" during the cathode phase, but this
unknown line always "come from the discharge". Another point is that
temporal evolution may be slightly different from the other ones.
The emiiter Material which is used consists of Barium Strontium and
Calcium and the gas in the lamp is Krypton and Argon.
What is that line had; why does it behave like that? Maybe one have a