The Neon Medium/High Pressure Arc-discharge Lamp

 

OPEN SOURCE EVERYTHING – QUESTION EVERYTHING

Q and A – A Discussion - Researchment, Questions and Expectations

Depiction of supposed ED28/ED90 HID Neon Lamps

Q - What is it intended to be, how to look like?

A - Consider it as the HID counterpart of the neon signs filled with neon, in the way as the Ar-Hg HID lamp is that counterpart of the neon-signs filled with Ar-Hg. 

Or, the HID version for neon, from the point of view of what means the HID mercury lamp.

Q - Was ever manufactured a similar lamp?

A - Not in a commercial form. But, as we know, long-time ago, there were some studies about, and some attempts to develop a compact HID neon lamp of this kind, with a higher lm/W red light, than so as were at that time the cold cathode neon beacon lights. But we do not have any papers from that time, nor would you find some satisfactory now.

 But you have instead a newer patent paper on this concern, that is really interesting. Here it is:

https://pdfpiw.uspto.gov/.piw?PageNum=0&docid=06593706&IDKey=4813F1FF4868%0D%0A&HomeUrl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fnph-Parser%3FSect1%3DPTO1%2526Sect2%3DHITOFF%2526d%3DPALL%2526p%3D1%2526u%3D%25252Fnetahtml%25252FPTO%25252Fsrchnum.htm%2526r%3D1%2526f%3DG%2526l%3D50%2526s1%3D6593706.PN.%2526OS%3DPN%2F6593706%2526RS%3DPN%2F6593706

Q - Why do you think that development not continued?

A - Don't know anything more about, but supposedly problems with electrodes and arc tube erosion. Or, anything else.

Q - And now? Are there greater chances of success?

A - From a commercial perspective, not. You have now red LEDs, and you can achieve, if you want, ED28/ED90 (clear or diffusing) filament LEDs of red color, with even up to ten times more lm/W. (But for beacon red lights you need an amount of IR emission too, beside of the visible light output).

Q - Again the questions, as in previous cases.

 Do you consider a researchment of all components from scratch, or do you rather consider to put together components that are already 'on market'?

A - Again, as long as it is intended to be a lamp for limited purposes, the intention is to put together as possible what is already at disposal.

Q - So, what do you need to put together in order to achieve the desired lamp?

A - The same, all the main component parts of a HID mercury lamp; - arc-tube, frame, outer bulb, stem, screw-cap: http://lamptech.co.uk/Documents/M1%20Introduction.htm

Q - What about the arc-tube? What is the preferred range of power for the desired lamps?

A - Let consider it around 250W, at least for the research case. 

Q - No more or less, but only 250W?

A - Yes. Concerning the low lm/W of expected neon discharge, the 250W might be considered not too much, but also enough high for, let say a 15-20lm/W, for a reliable output.

However, the arc tube needs to be made of alumina silicate hard glass instead of quartz glass.

Q - So, what rate of success do you expect in development of the under discussion lamp, or do you expect a reliable success of the experiment?

A - Ask please rather, what problems do you expect or do you have to overcome (because there are, believe!), before to discuss about the success into achieving a lamp that is similar with the incandescent one in its lm/W output.

Q - Yes! Then, why the entire discussion about this experiment? Or, is it somehow also the case of the N2 and CO2 lamps, discussed in a previous post? 

http://lightcommunitylighting.blogspot.com/2020/09/the-hydrogen-mediumhigh-pressure.html

Is it, let's say: - For the seek of the red light, and the idea itself, and also for the seek of research and portfolio of discharge lamps as a whole.

A - Hmm!... You guess it already...

Q - OK! but in that previous post you mean that: - You have now at disposal the dielectric barrier discharge lamp in a more advanced stage of development, so you can use it from start, in case of gases that are not 'noble'. But why do you not use it also for neon discharge, if there are or might be so big problems using a common HID lamp?

A - It leads very likely into excimer formation, so you get an excimer lamp, rather than a simple gas discharge lamp. And, yes! You have already neon excimer lamps, but as a source of far UV (VUV), not as one of red light.

Q - In earlier posts you speak about the neon-mercury HID lamp. Is this somehow a similar HID lamp as the well known mercury lamp, but filled with neon beside the mercury, instead of argon?

A - No! Or it might be only, but only, in its appearance, not as functionality. What we mean by the neon-mercury HID lamp is a lamp in which the main discharge remains in neon.

 - If you build a HID lamp with neon and mercury (similar to the mercury lamp with argon), after the warm up of the lamp, the mercury discharge will take over entirely the discharge process. It will simply keep out the neon gas to be longer involved in the discharge, instead keeping the neon only as a buffer gas. And this might be the case of 100 to 1, neon to mercury amounts, in pressure units of the hot lamp, or even more.

Q - And?!...

 A - Briefly, what have you to do is to rise up the difference, as much more neon and much less mercury, or to 'deplete' the mercury in the discharge process. And, in the case of medium or high pressure discharge,... anything but easy might it be...

Q - So, which one do you consider?

A - The first one, of course. The more, as long as you don't look to achieve a constant color or a constant lumen output.

Q - And, in what difference of neon and mercury pressure?

A - Again, only the research will answer, but,... as a speculation,... an 1000 to 1 would not be a surprise.

Q - In a previous post

http://lightcommunitylighting.blogspot.com/2019/12/the-high-pressure-neon-arc-lamp.html

you speak about a 'medium pressure neon-mercury discharge lamp', and that: It's main light spectrum is expected to come out from the discharge itself, and will be a reddish based spectrum. Let's say from light cyclamen to violet red, depending of the balance between neon and mercury (in discharge terms, not in 'weights').

How do you expect the spectrum depending on neon and mercury pressures? When cyclamen and when violet-red?

A - This is the desire, the goal of the experiment with neon-mercury HID lamp. In any way, it seems more easy for light cyclam, and more difficult for violet-red.

Q - Why so?

A - If you bring more blue and violet wavelength into the neon discharge, you will most likely get different nuances of cyclam or pink. It's about mixing wavelengths. In the plasma the wavelengths will 'mix'. But this is another subject. The violet-red will rather come out from the pure neon discharge with a violet glass, as a rough speculation. But with an efficiency that for sure will you consider inconvenient.

Q - Are the desired lamps expected to start directly, or would it be necessary a high voltage pulse.

A - Let's say, directly, at the supply voltage (of 220/230V) in case of internal starting electrode (and reactor ballast).

more content to come...

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