A source of large variety of light colors for esoteric use
Q and A - Researchment questions and expectations
Depiction of Medium Pressure Mercury Lamps
with Oversized Arc-tube and Outer Bulb
(lamps are shown as clear, for a better understanding)
Q - What is it intended to be, how to look like?
A - A medium pressure mercury lamp, in a form of a HID lamp, shaped as an ED/BT fluorescent coated bulb with an E33 or E(X)39/40 screw cap.
Q - Do you mean an E33 size of lamp screw cap, beside of the well known large ones?
A - Consider it as been in the way described here: http://lightcommunitylighting.blogspot.com/2018/01/e33-screw-caps-and-lampholders.html
A - Consider it as been in the way described here: http://lightcommunitylighting.blogspot.com/2018/01/e33-screw-caps-and-lampholders.html
Q - Was ever manufactured a similar lamp?
A - Yes, there is, and you find more details here: http://www.lamptech.co.uk/Spec%20Sheets/D%20MA%20GEC%20MAF400.htm
But thus is it the closest to what in discussion here, it is similar to only a certain extent.
But thus is it the closest to what in discussion here, it is similar to only a certain extent.
Q - 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 - As long as it is intended to be a lamp for limited purposes, for sure, the intention is to put together what is already at disposal.
Q - So, what do you need to put together in order to achieve the desired lamp?
A - For sure, 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 - We consider it from 75W to 400W.
Q - Do you somehow mean that some medium pressure UV lamps on the market, as there are, might be the arc tube, inside an ED/BT outer bulb, for your proposed lamp, at least in the research stage?
A - You are right.
Q - OK, but if we look for the medium pressure UV lamps, we find them as usual in the range of 1KW to even tens of KW, - isn't it?
A - Yes it is, but if you are in knowledge, you would say: Stop! You have missed the lamps used for photochemical reactors, that are as usual in the range of 125W, 250W, 400/450W, and even more,... and, the more, their UV spectrum has peaks at 254nm, 356nm and 365nm, and have also starting electrode.
- As another example, you find also 400W medium pressure mercury UV lamps (arc tubes) which burn in any position (not only horizontal), which are 31mm arc length, 14mm dia, and burn at 3,5A, 125V arc voltage, and roughly the same UV spectrum, but have no starting electrode.
Q - Yes, but you speak about even lower power, as low as 75W. Are there somewhere medium pressure UV lamps of so a low power?
A - Yes, there are on the market some lamps for photochemical reactors, of 150W dimmable as low as 75W.
Q - What about the outer bulb? Is it intended to be the same used for high-pressure mercury lamp used for general lighting?
A - Yes. The outer bulb (see image above) is the same, but it has to be at least one size larger than that corresponding to the same power of high pressure mercury lamps; i.e. for 75-125W medium pressure mercury the outer bulb has to be of ED28/ED90 size; for 250W it has to be of ED/BT37, ED/BT120, while for 400/450W it has to be of ED145/BT46/BT150.
Q - So, let say, for the first example, we will have an ED28/ED90 fluorescent coated bulb of 75-125W, - isn't it?
A - Yes, you are right! It is similar to the coated 175/250W high pressure mercury lamp.
Q - But there is seemingly one more problem. What about the fluorescent coating?
A - Now, the problem comes, and it's maybe the most difficult one. It's the one where unpleasant surprises might come during the research...
Q - Would you consider to use certain luminophores 'as there are' or rather would you try to develop new ones, consisting of mixtures of active substances?
A - For first, the desire may be to use fluorescent coatings as there are used for color light fluorescent tubes and neon signs, and as case might be, mixtures as well.
Q - OK! But you speak about lamps with color light output. And, as you also say, we know that most, if not all, nowadays fluorescent coatings for UV conversion in color light are used in fluorescent tubes, CFLs, and neon signs.
So, are you sure that if you use these coatings in an 'as-is' form, will these be proper for the compact ED/BT bulb working at high temperature? And will these coatings have a proper conversion for the UV into the colors of light as there work in fluorescent tubes, CFLs, and neon signs?
A - You are right! Here the problem comes in! And here the 'surprises' as well. Only due to testing one by one of the fluorescent coatings would you draw a conclusion...
Q - Is this why you consider to have an oversized outer bulb, to have a lower temperature for the fluorescent coating?
A - Yes, this is one of concerns, of course. And, the more, the ED-shaped bulbs have somehow a larger area than the BT-shaped of the same size, so the 'ED' ones might be preferred.
Q - Can you already expect something as a result, concerning the fluorescent coating?
A - At this stage is too early even to estimate or to speculate, before you have at least some certain results after testing. Anyway, the best desired outcome (preferable with as few testing as possible) will consist in achieving a coating which is sensitive for the peaks of UV spectrum of the medium pressure mercury lamp, but in order to result a light output efficiency of at least 70lm/W.
Q - Do you mean 70lm/W for any color?
A - For sure not! We mean 70lm/W for the standard white colors used in general lighting, of 2700 to 6500K.
Q - In this case, it seems you consider this type of lamp to be also useful for general lighting. Right?
A - Not necessary at this stage, but as the case might be, if successful, yes. But for now, the intent to achieve the white standard colors is only for the research purpose itself, to find how the results are in comparison with the high pressure mercury lamps and the fluorescent tubes. So, this might be in study at first, and thereafter other color lights will be in study as well.
Q - The depiction above shows uncoated lamps, with clear outer bulb. How does it fit, as long as the research intends to develop fluorescent lamps?
A - Bulbs are shown as been clear (uncoated) for a better understanding of the inside. But, if you ask it, the answer is: Yes, there are needed also the uncoated bulbs. The research will need them for reference, to find the lumen output of the medium pressure mercury lamps, as there are.
Q - What kind of glass has to be the outer bulb, and how large has it to be, for the clear (uncoated) experimental lamps?
Q - What about the arc-tube? What is the preferred range of power for the desired lamps?
A - We consider it from 75W to 400W.
Q - Do you somehow mean that some medium pressure UV lamps on the market, as there are, might be the arc tube, inside an ED/BT outer bulb, for your proposed lamp, at least in the research stage?
A - You are right.
Q - OK, but if we look for the medium pressure UV lamps, we find them as usual in the range of 1KW to even tens of KW, - isn't it?
A - Yes it is, but if you are in knowledge, you would say: Stop! You have missed the lamps used for photochemical reactors, that are as usual in the range of 125W, 250W, 400/450W, and even more,... and, the more, their UV spectrum has peaks at 254nm, 356nm and 365nm, and have also starting electrode.
- As another example, you find also 400W medium pressure mercury UV lamps (arc tubes) which burn in any position (not only horizontal), which are 31mm arc length, 14mm dia, and burn at 3,5A, 125V arc voltage, and roughly the same UV spectrum, but have no starting electrode.
Q - Yes, but you speak about even lower power, as low as 75W. Are there somewhere medium pressure UV lamps of so a low power?
A - Yes, there are on the market some lamps for photochemical reactors, of 150W dimmable as low as 75W.
Q - What about the outer bulb? Is it intended to be the same used for high-pressure mercury lamp used for general lighting?
A - Yes. The outer bulb (see image above) is the same, but it has to be at least one size larger than that corresponding to the same power of high pressure mercury lamps; i.e. for 75-125W medium pressure mercury the outer bulb has to be of ED28/ED90 size; for 250W it has to be of ED/BT37, ED/BT120, while for 400/450W it has to be of ED145/BT46/BT150.
Q - So, let say, for the first example, we will have an ED28/ED90 fluorescent coated bulb of 75-125W, - isn't it?
A - Yes, you are right! It is similar to the coated 175/250W high pressure mercury lamp.
Q - But there is seemingly one more problem. What about the fluorescent coating?
A - Now, the problem comes, and it's maybe the most difficult one. It's the one where unpleasant surprises might come during the research...
Q - Would you consider to use certain luminophores 'as there are' or rather would you try to develop new ones, consisting of mixtures of active substances?
A - For first, the desire may be to use fluorescent coatings as there are used for color light fluorescent tubes and neon signs, and as case might be, mixtures as well.
Q - OK! But you speak about lamps with color light output. And, as you also say, we know that most, if not all, nowadays fluorescent coatings for UV conversion in color light are used in fluorescent tubes, CFLs, and neon signs.
So, are you sure that if you use these coatings in an 'as-is' form, will these be proper for the compact ED/BT bulb working at high temperature? And will these coatings have a proper conversion for the UV into the colors of light as there work in fluorescent tubes, CFLs, and neon signs?
A - You are right! Here the problem comes in! And here the 'surprises' as well. Only due to testing one by one of the fluorescent coatings would you draw a conclusion...
Q - Is this why you consider to have an oversized outer bulb, to have a lower temperature for the fluorescent coating?
A - Yes, this is one of concerns, of course. And, the more, the ED-shaped bulbs have somehow a larger area than the BT-shaped of the same size, so the 'ED' ones might be preferred.
Q - Can you already expect something as a result, concerning the fluorescent coating?
A - At this stage is too early even to estimate or to speculate, before you have at least some certain results after testing. Anyway, the best desired outcome (preferable with as few testing as possible) will consist in achieving a coating which is sensitive for the peaks of UV spectrum of the medium pressure mercury lamp, but in order to result a light output efficiency of at least 70lm/W.
Q - Do you mean 70lm/W for any color?
A - For sure not! We mean 70lm/W for the standard white colors used in general lighting, of 2700 to 6500K.
Q - In this case, it seems you consider this type of lamp to be also useful for general lighting. Right?
A - Not necessary at this stage, but as the case might be, if successful, yes. But for now, the intent to achieve the white standard colors is only for the research purpose itself, to find how the results are in comparison with the high pressure mercury lamps and the fluorescent tubes. So, this might be in study at first, and thereafter other color lights will be in study as well.
Q - The depiction above shows uncoated lamps, with clear outer bulb. How does it fit, as long as the research intends to develop fluorescent lamps?
A - Bulbs are shown as been clear (uncoated) for a better understanding of the inside. But, if you ask it, the answer is: Yes, there are needed also the uncoated bulbs. The research will need them for reference, to find the lumen output of the medium pressure mercury lamps, as there are.
Q - What kind of glass has to be the outer bulb, and how large has it to be, for the clear (uncoated) experimental lamps?
A - It has to be the same used for coated bulbs, the same borosilicate glass used for the high pressure mercury lamps, of the size previously discussed. Consider the lamp the same, excepting the fluorescent coating. However, in some cases, if you need to find the UV spectrum of the assembled lamp, then you need also the outer-bulb to be transparent to UV.
Q - So, are you interested to block the UV and to get only the visible light from the uncoated lamps, in most of cases?
A - Yes, excepting some cases, we have to find out only the visible light output of the lamp and other working parameters as well. Measurements made on only the arc tube alone, as are for UV usages, are not conclusive, so we need it in the form and shape of the desired lamp, for also the other measurements, as described above.
A - Yes, excepting some cases, we have to find out only the visible light output of the lamp and other working parameters as well. Measurements made on only the arc tube alone, as are for UV usages, are not conclusive, so we need it in the form and shape of the desired lamp, for also the other measurements, as described above.
Q - Is it true that you seek, or even the research is lucky for, the case in which you have the optimal burning temperature for the arc tube, while the maximal temperature of the outer bulb at which the fluorescent coating still works properly on long term?
A - Yes! Exactly! This balance is the success of the experiment.
A - Yes! Exactly! This balance is the success of the experiment.
Q - Does the arc-tube need to be in vacuum inside the outer bulb, in order to remain hot while not heating too much the coating?
A - Most likely, yes. And the arc-tube might also be heat-reflective coated at ends.
A - Most likely, yes. And the arc-tube might also be heat-reflective coated at ends.
Q - And, are you sure that with an outer bulb with one size larger than 'normal' would you find this balance?
A - Not! But this has to be the starting point for the experiment.
A - Not! But this has to be the starting point for the experiment.
Q - Do you expect the same colors or color saturation as are for fluorescent tubes?
A - For sure not! You have to take into account that beside the conversion of the UV-C into visible, you have also a certain amount of visible light output. And, on the other hand, if you try to convert also the resulting UV-A into visible, this will also change the spectrum.
A - For sure not! You have to take into account that beside the conversion of the UV-C into visible, you have also a certain amount of visible light output. And, on the other hand, if you try to convert also the resulting UV-A into visible, this will also change the spectrum.
Q - Is it possible to get a jumble of unexpected wavelengths conversion leading to unexpected colors, too?
A - There is the likelihood to have unexpected colors that differ to an extent and saturation from that corresponding to the 254nm conversion. The more, if you use mixtures with phosphors for the near UV conversion.
A - There is the likelihood to have unexpected colors that differ to an extent and saturation from that corresponding to the 254nm conversion. The more, if you use mixtures with phosphors for the near UV conversion.
Q - So, have we to expect softer colors (than in fluorescent tubes) due to the bluish-white visible light and due to the conversion of UV-A into visible?
A - We can only speculate so an outcome, but also in this case only the research will give the final result. Surprises may come out, pleasant or unpleasant, as well. But you have to be open to all possibilities...
A - We can only speculate so an outcome, but also in this case only the research will give the final result. Surprises may come out, pleasant or unpleasant, as well. But you have to be open to all possibilities...
Q - The most reasonable expectance of the research success?
A - The 75-125W medium pressure UV arc-tube in the ED28/ED90 outer bulb, coated with fluorescent powders used for CFLs of all types, including the high powered for aquarium, hydroponics, and others.
A - The 75-125W medium pressure UV arc-tube in the ED28/ED90 outer bulb, coated with fluorescent powders used for CFLs of all types, including the high powered for aquarium, hydroponics, and others.
Q - As a conclusion for the attempt to use the coatings used in fluorescent tubes or neon signs for the HID lamps, even let's say of medium pressure mercury?
A - Realistically, you have to move your attention to other compact discharge lamps, with moderate heat output and narrow UV emission (similar to fluorescent tubes), as might be excimer lamps.
However, excimer lamps are an immature technology from many points of view, while the mercury lamps, as a whole, are a mature one from almost all points of view.
And, for a comprehensive answer, you have to put in balance the disadvantages (as possible mismatching, as resulting from above) of the mature technology of the mercury lamps (as a whole) with the advantages of the still immature technology of excimer lamps.
Q - And, the balance weights in favor of...?
A - The mercury lamps as a whole (fluorescent tubes, CFLs, medium pressure UV, HIDs) at least nowadays, and even, either to proof the maturity of their technology (in case of lack of success of this experiment), or to improve their maturity and portfolio, as the case might be, with the success of this research. May it be even partially or barely successful.
A - The mercury lamps as a whole (fluorescent tubes, CFLs, medium pressure UV, HIDs) at least nowadays, and even, either to proof the maturity of their technology (in case of lack of success of this experiment), or to improve their maturity and portfolio, as the case might be, with the success of this research. May it be even partially or barely successful.
some more content might come...
Image of medium pressure fluorescent coated mercury lamp with oversized outer bulb (BT46/BT150 for 400W lamp) and arc-tubeNotice!
The oversize of the arc-tube (comparative to that of high pressure mercury lamps) is not a sine-qua-non condition for the lamps in discussion, but the oversizing of the outer bulb is one.
Related post: https://lightcommunitylighting.blogspot.com/2018/05/blog-post_30.html
Cobra's up to date post: http://2012portal.blogspot.com/2020/08/eostres-gift-update.html
