Has anyone seen this before?
Amelia M. Samples
my first post...
I'm a collector of lightbulbs, and use one of my "plasma globes" to
check the discharge lamps I get to see if their arc tubes are still
gas intact. I recently acquired a few newer HPS lamps, they glowed as
normal when I applied the current from the globe, but when I removed
the power (turned the globe off) - the arc tube KEPT GLOWING...I know
that they keep glowing reddish orange normally when they cycle at EOL,
but I have never seen this phenomenon before. When I had the lamp
connected to the output (direct coupled - output wire of flyback
directly connected to bulb base) the lamp glowed the usual Ar/Xe
spectrum, with the Na color at the electrodes like I have seen so many
times before...but when I turned the globe off, the arc tube was
luminescent - only the discharge streamer and Na color had gone, and
the intensity was reduced. I have pictures at my site...
www.clubsilicon.com/naglowpowered.jpg
www.clubsilicon.com/naglowunpowered.jpg
Does anyone know what's going on here? I've never heard of luminescent
aluminum oxide before...then lamp in question is a Sylvania Lumalux 200W
that appears unused. I went thru a small pile of lamps, my SLI lamps showed
no trace of this effect (as well as showing Ne color in the starting
discharge), a couple of used GE 1000W lamps showed a bit of glow, but not
nearly as much as the Lumalux.
Don Klipstein
I have seen this before sometimes. Some HPS arc tubes do phosphoresce
after operation at low current and low temperature (room temperature). I
think it's a couple older (but in new condition) 1 KW GE "Lucalox" lamps
that did this for me. I somewhat remember my arc tube afterglow being
reddish.
Mercury vapor lamp arc tubes often have some dim afterglow after being
operated at low current at room temperature.
- Don Klipstein (d...@misty.com)
Ioannis
news:slrnbs21p...@manx.misty.com...
[snip]
> Mercury vapor lamp arc tubes often have some dim afterglow after being
> operated at low current at room temperature.
Let me also add that the actual quartz tube in high pressure mercury lamps,
actually fluoresces some.
I have no idea what frequency of mercury does that, but when you turn off a
clear mercury, you can see the actual fluorescence of the quartz, while the
tube contents are still hot, provided you block instantaneously the light
from the previously lit lamp.
> - Don Klipstein (d...@misty.com)
--
Ioannis Galidakis
http://users.forthnet.gr/ath/jgal/
------------------------------------------
Eventually, _everything_ is understandable
Ioannis
news:Pp7wb.85085$M02....@twister.rdc-kc.rr.com...
It is not uncommon to test discharge tubes by applying high frequency
currents to the tube directly using a Tesla coil.
Once sparked with a high frequency current, many tubes continue to glow
afterwards.
This can also be done on longer fluorescent tubes, which once sparked with
high frequency, may continue to glow for quite some time after the actual
application of the current.
You can cause a discharge tube to glow even from afar, by sparking the tube
walls.
I suspect that the plasma globe in your case, probably acts as a Tesla coil.
Check what kind of current the globe produces. If it's high frequency,
there's your answer.
nanotech1
spot light ( the 1,000,000 c.p. type )
if you turn it off after a 3 or more min of operation you will see a faith
blue glow of the quarts envelope that dims away in about 30 sec to one min
( it suprized me when i notice it the first time i saw it )
the way i analysed it is the halogen or any other gas get charge with excess
electrons and when it is turn off the electrons
discharge to the surrunding envelope witch may have a little fluorescent
propriety that gives the glowing
please correct me if i am wrong
Amelia M. Samples
power off - I love demoing the distance glow for friends..."look - it lights
up when I hold it...;)" - I've just never noticed that blue glow after the
RF field was removed. It is almost a Cerenkov
(http://nova.nuc.umr.edu/~ans/cerenkov.html) - color...maybe I can save this
pic and scare my friends with the "atomic light bulb" (it contains atoms, so
technically, it's true;))
thanks...
A
"Ioannis" <morp...@olympus.mons> wrote in message
news:1069622399.933713@athprx02...
Ioannis
>
> It is a HF output, but what perplexed me was the glow after I turned the
> power off - I love demoing the distance glow for friends..."look - it
lights
> up when I hold it...;)" - I've just never noticed that blue glow after the
> RF field was removed. It is almost a Cerenkov
> (http://nova.nuc.umr.edu/~ans/cerenkov.html) - color...maybe I can save
this
> pic and scare my friends with the "atomic light bulb" (it contains atoms,
so
> technically, it's true;))
It almost certainly cannot be Cerenkov radiation, although it may look like
it in terms of color.
If in doubt, you could easily examine the spectrum of the emission, but my
guess is that it is Xenon radiation for regular HPS's and it will most
likely be Neon radiation for HPS retrofit lamps.
Pass the light through a small spectroscope and tell us what it is.
> thanks...
> A
Daniel Stern Lighting
> times before...but when I turned the globe off, the arc tube was
> luminescent - only the discharge streamer and Na color had gone, and the
> intensity was reduced. I have pictures at my site...
> www.clubsilicon.com/naglowunpowered.jpg Does anyone know what's going on
> here?
Amelia, I posted a very similar question a couple years ago related to an
automotive MH burner exhibiting a very similar blue afterglow. Got several
good answers. Thread is here: http://tinyurl.com/wcwp
DS
Don Klipstein
>
>Pass the light through a small spectroscope and tell us what it is.
I remember doing that with my 1KW GE "Lucalox" and saw a single line
somewhere in the red. Makes me think some trace of something in the arc
tube material, definitely not anything glowing in the gas. Maybe
strontium, maybe europium, maybe who knows what??? I no longer remember
whether it is near 610 nm (orangish) or further out in the red.
Some Philips UV-absorbing doped quartz (or possibly hard glass) bulbs
fluoresce/phosphoresce whitish slightly greenish blue, and that has a
broad continuous spectrum.
- Don Klipstein (d...@misty.com)
Ioannis
>
> In article <1069677617.722777@athprx02>, Ioannis wrote:
> >
> >Pass the light through a small spectroscope and tell us what it is.
>
> I remember doing that with my 1KW GE "Lucalox" and saw a single line
> somewhere in the red. Makes me think some trace of something in the arc
> tube material, definitely not anything glowing in the gas. Maybe
> strontium, maybe europium, maybe who knows what??? I no longer remember
> whether it is near 610 nm (orangish) or further out in the red.
6160A maybe? That's one of the Sodium doublets left of the D line. It really
gets accentuated in HPS's. The Lucalox is a HPS or am I mistaken?
> Some Philips UV-absorbing doped quartz (or possibly hard glass) bulbs
> fluoresce/phosphoresce whitish slightly greenish blue, and that has a
> broad continuous spectrum.
>
> - Don Klipstein (d...@misty.com)
Amelia M. Samples
the lab...
A
"Daniel Stern Lighting" <das...@vrx.headlamp.net> wrote in message
news:Pine.SOL.4.44.031124...@alumni.engin.umich.edu...
Don Klipstein
>
>Ο "Don Klipstein" <d...@manx.misty.com> έγραψε στο μήνυμα
>news:slrnbs5vb...@manx.misty.com...
>>
>> In article <1069677617.722777@athprx02>, Ioannis wrote:
>> >
>> >Pass the light through a small spectroscope and tell us what it is.
>>
>> I remember doing that with my 1KW GE "Lucalox" and saw a single line
>> somewhere in the red. Makes me think some trace of something in the arc
>> tube material, definitely not anything glowing in the gas. Maybe
>> strontium, maybe europium, maybe who knows what??? I no longer remember
>> whether it is near 610 nm (orangish) or further out in the red.
>
>6160A maybe? That's one of the Sodium doublets left of the D line. It
>really gets accentuated in HPS's. The Lucalox is a HPS or am I mistaken?
I am familiar with that one, and I thought the lamp needed to be warmed
up enough to get some sodium vapor in order to do that.
If it was sodium, then it was the only sodium line being produced.
I did not see any 515 nm at the time, and both that and the 616 nm ones
are S to 3P transitions.
The lamp was cold and getting low current, and the radiation from the
discharge looked like just xenon radiation.
- Don Klipstein (d...@misty.com)
Ioannis
[snip]
> I am familiar with that one, and I thought the lamp needed to be warmed
> up enough to get some sodium vapor in order to do that.
> If it was sodium, then it was the only sodium line being produced.
> I did not see any 515 nm at the time, and both that and the 616 nm ones
> are S to 3P transitions.
>
> The lamp was cold and getting low current, and the radiation from the
> discharge looked like just xenon radiation.
What may occasionally happen, is one can get temporary "bursts" from
internal contaminants which cannot be duplicated. If you cannot duplicate
the display of the specific line, I would surmize that it was probably a
temporary contaminant that flared up.
I've seen temprary flares of Argon for example in HPM, that I was unable to
duplicate under normal operating conditions. They just show up, particularly
when the lamp is in the process of warming up, for a split second or so and
then completely disappear.
I've also seen very fast Na spectrum flares while a HPS is still in the
process of warming up and the discharge is dominated by Xe.
I was succesful in reproducing the Argon flares for an extended period of
time by driving some mercury quartz tubes under VERY high currents, for a
short time. (For example 120A for an 80W HPM, with disabled seals).
DON'T try this yourself. :*)
Amelia M. Samples
couple of other new Lumalux lamps, but no other manufacturer's lamps will do
it. I also noticed a glow in the glass envelope. After the long weekend
(everything's closed) - I'll try to get in the lab...thanks to the group for
the help...
me
"Ioannis" <morp...@olympus.mons> wrote in message
news:1069890039.54238@athprx02...
> ? "Don Klipstein" <d...@manx.misty.com> ?????? ??? ??????