Talk:Electron-stimulated luminescence

From Wikipedia, the free encyclopedia
Jump to: navigation, search
WikiProject Energy  
WikiProject icon This article is within the scope of WikiProject Energy, a collaborative effort to improve the coverage of Energy on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.
 ???  This article has not yet received a rating on the project's quality scale.
 ???  This article has not yet received a rating on the project's importance scale.
 

Edits[edit]

Added non-proprietary product specifications per editor talk. More specs are in the process of review/approval for public dissemination. —Preceding unsigned comment added by 67.51.126.206 (talk) 18:06, 2 December 2010 (UTC)

Missing information[edit]

The company Web site is uninformative. A patent number would be very helpful. How many lumens/watt? How does it work? Cross section thorugh a lamp would be very interesting. It sounds like a variation on a vacuum fluorescent display, but they must do something special with the phosphors to get competitive efficiency at what must be fairly low operating voltage (say, around 300 V for a voltage doubler power supply operating off a 120 VAC line). Or they've got a flyback converter in the bulb base and are shooting out electrons at 15 kV. The biggest single loss in a modern fluorescent lamp is the conversion from short-wavelength UV to visible light, and nothing short of the legendary two-photon phosphor is going to change that. --Wtshymanski (talk) 19:27, 29 November 2010 (UTC)

Check out [1]], a WIP patent application. Cross section through the bulb, but no numbers, though. --Wtshymanski (talk) 19:45, 29 November 2010 (UTC)
Since this device doesn't make UV first to excite the phosphor, and doesn't even need to overcome cathode drop to strike an arc, it can afford some inefficiencies in the wall-plug to DC stage and still come out ahead. If existing CFL phosphors give about as many lumens from a watt of electrons as from a watt of UV, there's a great gain to be had. But...how does it dim? Same problem as a CFL, the "peak-picking" input rectifier stage doesn't reduce output well on a phase-cutting dimmer. How long does the emitter take to warm up? Today's LCD generation doesn't remember waiting for the TV to warm up - there may be some delay there, thoguh possibly small. There would be at least as much electronics in the base of the tube as for a CFL, though the patent application doesn't show a schematic for the DC/DC stage; heat dissipation would still be a concern. The bulb looks simpler to make since there's no spiral or bundle of small tubes. The conductive coating is going to cost some lumens, and I bet the phosphor isn't made by grinding up some rocks off the beach, either. So many questions, and no facts on their Web site. --~!Wtshymanski (talk)
A general description of what R30 bulbs are used for is no specific help in describing *this* product. How many lumens will it make per watt? What is its CRI? Has it been tested to Energy Star requirements for CFLs? Yes, it's not exactly a CFL but it's got to compete with a well-established product that you can buy anywhere for about $2. --Wtshymanski (talk) 21:27, 2 December 2010 (UTC)

Reliable sources[edit]

Could we please get some Wikipedia:Reliable sources for information? This specifically excludes press releases handed out by the company. No, citing that press release on some McNews web site doesn't make it reliable. --Wtshymanski (talk) 16:28, 8 December 2010 (UTC)

I'm not sure I would characterize Popular Science as a "McNews web site." Their coverage was purely editorial, not generated from a press release. Please understand that much of the primary-source scientific background you're requesting is proprietary to the company that developed the technology. Also, I thought secondary sources were preferred by Wikipedia as they are more credible than primary sources. — Preceding unsigned comment added by Prguy72 (talkcontribs) 18:02, 15 December 2010 (UTC)

Lumens/watt[edit]

Still no released product data but the company's web site says [2] 600 lumens with 19.5 watts input; 31 lumens/watt. That wouldn't make the Energy Star limits for a CFL with comparable output. It's around half the efficacy of Energy Star CFLs. And it's been over a year and still no bulbs on shelves? What is the hold-up, that's the real story which the journaists aren't finding in the company press releases. --Wtshymanski (talk) 18:38, 15 December 2010 (UTC)

As you probably know, the DoE's Energy Star program is fraught with political influence and general ignorance, and has been the subject of much disagreement among manufacturers from a variety of industries - not just lighting. I worked in the household appliance industry in the 2000s and our product developers were always complaining about the Energy Star certification process and its political overtones.

Over the years, the DoE has trumpeted solid-state lighting with LED technology as the "heir apparent" to the incandescent light bulb and has subsidized the development of LED lighting by U.S. manufacturers to the tune of hundreds of millions of dollars. ESL inventors don't claim the technology is more energy efficient than CFLs (the power factor issue notwithstanding), but the real differentiation comes with the quality of light output (which, of course, is subjective) and the fact that ESL lamps are mercury-free. As a long-term, sustainable, low-cost alternative to incandescent lamps, ESL technology has a place in the market even without Energy Star certification.

Regarding the long go-to-market timeline, I can't answer that definitively. While I do represent the company that makes these bulbs, I'm (obviously) not an electrical engineer, and I'm not paid to edit these articles. So I hope you agree there is no COI here. But I do think the technology is worthy of mention in relevant articles, simply because it's a unique solution to the ongoing CFL vs. incandescent debate and a great example of U.S. scientific ingenuity. Just when we thought CRT televisions were headed to the technology graveyard, we figure out a way to make it useful again. Prguy72 (talk) 19:59, 15 December 2010 (UTC)

Confused[edit]

OK I am a little confused - WP:RS suggests that news reporting from a reliable news organization is usually considered a reliable source. Yet because it contains information from a press release (properly attributed by the author, I might add) it is suddenly unreliable? Since Wikipedia seems to frown on tertiary or primary sources for attribution, I feel like I'm damned if I do, damned if I don't with this one. Prguy72 (talk) 22:39, 15 December 2010 (UTC)

It would be nice to find a source from someone who's actually seen a bulb, not just press releases. It reminds me of EEStor - lots of press, lots of speculation, no hardware in the hands of the cold uncaring world. It doesn't matter how many "news" sources get the same press release, if there's no new information. A press release I'd like to see would explain why the trumpets have been blowing for 18 months and there's still no product.

--Wtshymanski (talk) 22:53, 15 December 2010 (UTC)

Hey, EEStor went for UL approval 15 months ago...and they, too, still have no product. --Wtshymanski (talk) 22:54, 15 December 2010 (UTC)

I assure you this is for real - I have two bulbs (slated for retail - not prototypes) sitting on my desk right now, and one more (prototype) in a recessed can in my media room at home. And it's everything the company says it is - great light quality and much cheaper than LED. I completely understand the skepticism, and the need to be neutral. But this technology is for real. Will it be a game-changer? Who knows. Investors certainly hope so. But I have no dog in this fight. I just want Wiki users to know the tech is real and ready for market, and an alternative to energy-efficient bulbs available today. Prguy72 (talk) 23:08, 15 December 2010 (UTC)

The patent application says the lamp uses an indirectly heated cathode. Does this take any perceptible time to warm up in commercial lamps? Is the cathode heating regulated some how to prevent loss of emission when the lamp is dimmed on a phase-cutting dimmer? In a fluorescent lamp, a big fundamental limitation is converting high-energy UV to much lower energy visible photons. How efficient is a watt worth of electron beam in making lumens? I'm not familiar with the literature on phosphors, can the company say anything about how much improvement is likely in efficacy in future devices? How tolerant is the lamp of stray heavy ions in the enclosure...I assume unlike a CFL or incandescent lamp, these bulbs are high vacuum devices, there must be a getter or something to clean up the last traces. The electronics must include some kind of voltage multiplier; it's already challenging to keep a CFL converter running in a lamp socket, it will be interesting to see how the multiplier stands up. If the efficacy could match that of Energy Star, when the cost comes down a bit it could be a CFL-killer. It's a much simpler bulb shape to manufacture, for one...all those shut down incandescent bulb factories could make it. I look forward to seeing the product on the market and seeing some real reviews. It'd be cool to get a sample, but they are probably only sampling to the Home Depots and Walmarts at this stage. --Wtshymanski (talk) 03:17, 16 December 2010 (UTC)
It would really help to have the US patent numbers for this...--Wtshymanski (talk) 03:32, 16 December 2010 (UTC)

X-ray emission?[edit]

Which acceleration voltage does the lamp use, and does it generate x-rays? —Preceding unsigned comment added by 213.108.248.89 (talk) 15:51, 1 February 2011 (UTC)

<years later> The VU1 corporation Web site has an annual report for 2012 in it, which gives a cross section of their lamp. The acceleration potential is around 5000 volts. This doesn't sound like a problem for X-ray emission, old time color TVs only got into trouble at more than 35,000 volts acceleration. A more serious problem is that they don't have any product out - they aren't even selling sample bulbs any more (they had $8000 - eight thousand - that's not even one bulb per Home Depot store - in sales for 2011 and nothing in 2012) and they are burning through capital at a non-trivial rate. --Wtshymanski (talk) 14:34, 24 April 2013 (UTC)