ESL Lightbulbs Better Than CFL, LED?

[g00ey]

Radiation from molecules

As well as the electronic transitions discussed above, the energy of a molecule can also change via rotational, vibrational and vibronic (combined vibrational and electronic) transitions. These energy transitions often lead to closely-spaced groups of many different spectral lines, known as spectral bands. Unresolved band spectra may appear as a spectral continuum.

 

[annymmo]

[citation][nom]g00ey[/nom]The only lights that produce real "continuous"-spectrum are the filament based ones which are also known as "black-body" radiators. The problem with these is that they cannot glow at the same temperature as the sun because the filament will evaporate way before that temperature is reached. The closest step to this is the halogen lamps which contain a halogen gas that reacts with the metal fumes and deposits them back to the filament. But still, halogen lights are nowhere near the 6000K which is the average black-body temperature of the surface of the sun.The closest artifical light is the sulphur plasma light and from what I've seen on diagrams, its spectrum almost perfectly follows the continuous spectrum of the sunlight. I've been wondering how it is possible for a fluorescent light to produce such a spectrum which is a little contradictory if you've taken a course in quantum physics. While I have no reasonable explanation my guess is that the light comes from sulphur molecules which may allow for a more continuous spectrum than pure atoms/ions, and/or it may come from their interaction with the microwaves. I think S2 is a dipole and dipoles interact with microwaves in a certain way which momentarily may produce heat-like movements of the molecules.I'm not working for a lamp manufacturer, I'm just dreaming of having sunlight in my living room for there is not much sunshine where I live...[/citation]

The key to your question is to consider what is needed for that light, and make some distinctions. The warmth in the sun delivers energy for heating up as a black body. You can also use electrical energy for getting light with the same energy as the sun. Electrical energy has current: I and potential U. The power P also varies locally because of various effects. LED's that produce blue light: For a black body to produce blue light, you need around 6000°K (Degrees kelvin) = 10 340.33 degrees Fahrenheit. The potential that gives elektrons energy is between 1 and 3 volts. The energy is about 1 to 3 eV.
Point is, warmth is just one form of energy.
Now the other thing, the visible spectrum is just a tiny piece of the EM-spectrum. If you can see all the colours and a continuis spectrum that only means that the VISIBLE part of the EM-spectrum looks like this! You can not conclude that it is a black body.

http/www.antonine-education.co.uk/physics_gcse/Unit_1/Topic_5/em_spectrum.jpg

 

[annymmo]

The temperature of a LED must stay below 200°C = 392°F in it's active zone, or else it gets destroyed.

 

[g00ey]

I don't understand your comment annymmo. The emission spectrum of a black-body radiator follows a continuous Planck distribution (see Planck's law on wikipedia). The only true replication of the sun's (visible) spectrum is to use a filament heated to the same temperature as the sun's surface which is not possible as of today since the filament would evaporate within a split-second.

The other way is to use fluorescent light but the spectrum is nowhere near the visible spectrum of sunlight. What manufacturers and the like are doing is to make a mixture of chemicals so that the light resembles the sunlight which is nowhere near same thing, even though there are such lights in the market with temperatures specified.

 

[Guest]

Seems to be similar in layout to a plasma(TV) or a CRT, where electrons are sprayed at a screen. That explains why they are putting it out as an R30 flood light first. This layout fits the technology better. They are probably having a difficult time fitting any other form factor.

 

[Ciuy]

CFL sucks but lasts a long time )

Anyway i still use incandescence bulps , sucks at aco but darn it gives good light . gl

 

[heman1320]

incandescents are still the right answer. I say this because the problem is not so much how to use less energy but how to make that energy cleaner and cheaper. The money saved from a CFL or ESL will mean nothing if energy prices keep going up. Don't get me wrong efficiency of light bulbs needs to be handled but I think that should be a concern after we solve the energy problem.

 

[g00ey]

A bunch of strong 12V (35-50W) halogen lights is the best in my taste. They deliver such a crisp and strong light that is refreshing, almost like sunshine. The 240V/120V versions are not so good but the 12V are really awesome.

 

[Guest]

You might want to look at cold cathode flourecent made by litetronics and tcp among others. as a 25 year ee lighting professional this is an excellent proven technology.

fully dimmable, much smaller than cfl, uo to 25,000 hours.

all the best

 

[Guest]

LEDs are MUCH more efficient than either CFL's or ESL. They also have no mercury and produce virtually no heat (the heat they mention must be from resistors necessary to drop the voltage when using an LED in a traditional socket - but it certainly isn't as much heat as a regular bulb. LEDs can be adjusted to produce virtually any color. It's true they aren't particularly suited to replace standard bulbs and ideally work in strips or arrays. But in my opinion, it's a much better, safer, cooler and efficient technology and the direction we should be moving in.

 

[hevic]

Does anyone have ANY info on the specs of these lights? what incandescent bulb are they comparing it to? 100W? 500W? where's the lumens per watt? the colour info? More info is needed before i blindly charge into buying ESLs, as tempting as they make them sound.

 

[Guest]

if mrecury is dangerous why do the authorities allow it?

 

[james_ledlightmaker]

Not right time to compare them.
LED pre-mature ,too expensive, not massive produced.
Well,we sell led lights,all kinds of. please go to www.ledlightmaker.com and have a look

Regards
James

 

[Anders Hoveland]

ESL technology supposedly emits light with a "softer" quality than LED or CFL, and this bears out if we look at the spectral graph. This does not have to do with CRI, by the way. I have tried the latest 95 CRI LED, and while it has good color rendering, there is also still something about the light that seems a little harsh. It's that blue frequency spike.

In contrast, the light from both incandescent and natural sunlight coming through a window have a softer feel. Electroluminescent panels are another technology that can offer soft light, though the current technology can only offer low levels of lighting, more suitable for signs and decorative architectural purposes.

 

[Anders Hoveland]

The cathode ray tube in the ESL bulb does not emit X-rays. Unlike in a regular TV tube, the electron beam does not need to be focused. This allows the electron beam to have a lower voltage (about 5000 volts in this case), and so any X-rays produced are much "softer" and easily absorbed by the thick glass. The company did testing, and claims the detectable X-rays are lower than background levels, essentially absolutely nothing to worry about.

I also wanted to add that I cannot use CFL bulbs because they leak out UV radiation and I have a sensitivity to it. It makes my eyes ache and my skin feel sore after about 10-20 minutes of exposure. CFLs work by passing an electric discharge through the mercury vapor inside, producing UV radiation that then makes the phosphor coating glow. But some of this UV leaks out. I seem to be several times more sensitive to CFL bulbs than sunlight, in case you were wondering. Especially if I am sitting close to one, or the room has 5 or 6 spiral CFL bulbs in the room.

Thankfully, the new ESL bulbs do not emit UV radiation, not as far as I know.