Re: green plasma globe

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: David Speck <dave@xxxxxxxxxxxxxxxx>

OK, Guys,
Hat in hand, I stand most thoroughly corrected about the components of the 
green plasma globes.

I heard back from Scott Fusare, who worked for Bill Parker at one time.
His response is quoted below, with his permission.
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  I don't often peruse the TCML archives, but did happen to catch this 
thread. I am not sure
how to post to the list so I will respond through you if that's OK?

  Bill Parker's exact mixes are indeed a closely held secret. It would not 
be much of a
stretch to call him paranoid in this aspect. Seems there is a lot of bad 
blood stemming from way
back into the 70's and early 80's in the plasma artist community. Bill's 
one (and to my
knowledge, only) patent in the plasma globe arena holds the clue you are 
after. All gas mixes
referenced in this patent contain trace additions of one of the halogens 
(it varied with the
mix). The halogens briefly "combine" with the noble buffer gas (helium 
usually) in an eximer
type of process. Apparently the deep UV generated from the decay of these 
compounds
excites states in the remaining gasses that would not normally be dominant 
during the
"standard" electrical excitation, hence the pretty colors! That's about all 
I can say without
fear of violating the N.D.A. I signed when working with him. Hope it helps.
Scott Fusare
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Just to make thing interesting, check out Parker's patents online.  See 
them at uspto.gov.

Patent #4,963,792 includes formulas and pressures for 9 different gas mixtures.

Some of them include Oxygen, and others include chlorine, bromine, and 
fluorine.
I was previously under the impression that only inert gasses were used, but 
that sure doesn't seem to be the case.

Now, the only problem is to figure out which mix gave which color.

Anyone have a really big gas manifold in which they can do some fancy mixing?

Dave

Tesla list wrote:

> Original poster: Vladimiro Mazzilli <mazvla@xxxxxx>
>
> I've seen in a Paris scientific museum a plasma globe with normal clear
> glass a very nice dancing discharge of intense green colour and
> I've seen it another time in a plasma globe site without explanation.
> Anyone know the gas mixture.
>
>
> Cheers
>
> Vladi.