I do not need to correct myself :-) and might add you have mis-read this and misexplained
some things

I think it is more "Sorry Pszemol" please correct yourself : -)

"which is not true to my knowledge. They do get ionized and they
emit UV light, which is turned into visible rays of light by the phosphors
mixture on the internal surface of the tubes... "

Well, that is incorrect as the bulb does not generate enough energy to ionize Argon. What
makes you think it does.Only HID generate enough energy to ionize Argon. Do you have ref.
that states that Argon in fluro lamp gets ionized and produces light or are you just
assuming that ?

"If you use UV-transparent glass
type to make the tube and do not use phosphors you would get the UV fluorescent tube."

It is the Mercury that becomes vaporized and ionized that does that, producing UV not
Argon. You will only see Argon peaks in HID bulbs.


"It is not the pressure which generates light. "

I never said pressure generates light, I said

"Increasing bulb
pressure alone increases output, as the argon gas pressure increases, due to added heat
and overdrive"

and

"Gas pressure = more lumens / watt"


Know where did I say pressure produces light, I said pressure increases output. A bulb
with no Argon gas, thus less pressure from heating and will have a lower efficacy rating
than one with Argon. An Argon filled bulb would have a higher efficacy than a non-Argon
filled bulb. The pressure reaches about 2-3 torr. Pressure lowers the wattage required to
attain x lumens / W. Nowhere in the GTE manuals does it even mention that Argon adds at
all to the spectrum and there is no Argon peak in any SED Curve

This is how things work;
When a fluro receives electrical current there is a passage of that current through the
electrodes, called "Hot Electrodes", sealed at either end of the bulb. The heat generated
heats up the tungsten filament and its emissive material such as Barium, Strontium,
Calcium Oxide). As then become heated (950 C) they release electrons. These electrons
travel at high speed from one electrode to another. Other electrons are also released by
the field differences of the electrodes. This produces an electrical discharge arch or
plasma. As these electrons and arch are produced it increases internal pressure, causing
liquid Mercury in the tube to become heated, causing it to become vaporized and shed
electrons. This release of electrons from Mercury produces UV light. These electrons fall
back into orbit but only to be re-released again as the bulb is still receiving current.
This "reaction" thus formed produces energy in the form of light and heat. The light so
produced is UV at 253.7 nm. As this wave length hits the phosphors, materials that are
capable of converting wavelengths from short UV to longer visible wave lengths, there is a
change in the type of light. In other words these phosphors are excited to fluorescence by
UV to the proper wave length.

Some known examples of phosphors and their colors

Cadmium Borate = Pink

Calcium Halophospahte = White

Calcium Silicate = Orange

Calcium Tungstate = Blue

Magnesium Tungstate = Bluish White

Strontium Halophosphate = Light Green

Zinc Silicate = Green


Please consult

GTE Sylvania Engineering Bulletin 0-341 (version 1 & 2 ), Fluorescent Lamps, 22 pages



--
Boomer

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If You See Me Running You Better Catch-Up
"Pszemol" wrote in message ...
: "Boomer" wrote in message
...
: meaning Fluro's are filled with Argon gas, the purpose for it in these bulbs is to
become
: heated and increase the gas pressure. Gas pressure = more lumens / watt.. In MH, MV,
HPS
: and LPS it is used for the same thing, but some of it also get ionized and adds to the
: light spectrum, so it is a duel purpose in these bulbs.
:
: Boomer, please, do not dissappoint me in your wisdom and correct yourself, please :-))
: From above statement we can read that gases in the fluorescent tubes do not
: get ionized, which is not true to my knowledge. They do get ionized and they
: emit UV light, which is turned into visible rays of light by the phosphors
: mixture on the internal surface of the tubes... The ionization process is started
: by the high voltage surge when the bulb is powered on. Starting voltage is about 600V
: and depends highly on the lenght of the tube and the temperature of filaments on both
: ends. Traditional tubes had filaments heated to support tube starting with lowered
: voltages. The new designs have rather high voltage and no heating.
: The bottom line: If you use UV-transparent glass
: type to make the tube and do not use phosphors you would get the UV fluorescent tube.
: It is not the pressure which generates light. It is UV rays of ionized gas induce
: secondary emission from phosphors on the tube surface in the visible part of spectrum.
: The pressure may influence other factors, but the pressure itself does not
: generate light - sorry Boomer :-)
:
: And to much pressure can make the
: bulbs go Kaboom, such as screwing a 175 watt into a 250 and a 400 for sure.
:
: Exactly - The increased risk of glass shattering is another reason against overdriving.
: I should mentioned this on my list before :-)
:
: p.s. Petition to The King Marc: do not interprete my message as aggressive again :-))))