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Can anyone provide evidence that infrared laser diodes are used in remote controls? A quick scan of the laser diode article and the remote control article doesn't seem to support this wording. The remote for my VCR, for example, does use an infrared diode, but certainly doesn't use an infrared laser diode to lase and emit an infrared laser beam - that would mean you'd have to point it RIGHT at the remote sensor for the signal to be received.
If someone can justify leaving the "infrared laser diode" entry in the applications section, reply here, but otherwise I'll change it to read "infrared diode" instead.
Abqwildcat 18:18, 28 May 2004 (UTC)
Actually, the issue of the beam opening depends also on the coupling between the emitting device and the air, so you could potentially have a laser source with a wider spread. But cost is the main factor of choice.[islay16years]
Actually, I believe diode lasers generally have a pretty darn awful angle of divergence and without a collimator lens they don't create anything close to a beam. But despite the zoomy name, their output power isn't much different from that of an IR LED (if not inferior). They're easily fried and require a monitoring circuit, and at maybe 100 times the cost I can't think of a single reason why one would use a laser in a remote. Typical IR LEDs are available with 'angles of half intensity' ranging from ±10° to ±60°. Remote LEDs are driven with short but intense bursts of current and the driver circuit may become tricky (read: half a cent more). A narrower beam needs much less power for the same angular intensity than a wide beam that illuminates half the room. Guess which LED type gets chosen. Femto 11:27, 15 Dec 2004 (UTC)
I have noticed that if you own a camera with a "nightvision" mode, you are able to see the IR LED transmitting to the receiver. Turn all your lights off, turn nightvision on, and then press some buttons. I have tried this with many remote controls and they all do this. Therefore that leads me to believe that they are in fact regular LED's.
What is the proper terminology when referring to a light fixture that uses LED technology, would I call it an LED lamped fixture? reply to klewis@cncarley.com
So OLED LEDs are 10% efficient? What does that mean? How efficient are other types and colors? Can someone connect the dots between the percent efficiency and the lumens/watt? Omegatron 21:45, Feb 19, 2004 (UTC)
I cleaned up the section on OLEDs, which was unclear. I had to infer some of the information -- I'm not a domain expert. Care to verify I haven't introduced inaccuracies? --Anonymous
No one talk about Luxeon yet. :o). D@mn, I wish I have enough technical English to write an article about it.
Helloooooooooooo, any flashaholics/CPFer here?
There is a description of 1W and 5W LEDs near the end of LED technology section. It does not mention Luxeon by name; there are other manufacturers of high-power LEDs.
From the SI article:
Similarly it is ' candela' not 'candelas', ' metre' not 'metres' or 'meters'. 213.51.209.230 11:29, 9 Oct 2004 (UTC)
Ooops. Confusion arising, very simple. Technically 60 W, or 60 Watt lamp. No problem. In common language (anywhere) one has: "I was 3 meters away from him, and I could not hit him with a 2 meter (2 m) rod". End of story.
I removed a dispute tag (no actual dispute ever existed so far as I can see) and the following paragraph:
"The above list is taken from public sources, but at least one LED given as blue does not produce blue light. (There is a good chance that almost none do, because of the higher frequency of blue.) This is a common problem in daily life due to the majority of mankind being ignorant of colour theory and conflating blue with light blue with cyan, the latter often called "sky blue". A cyan LED may be distinguished from a blue LED in that adding a yellow phosphor to the output makes green, rather than white light. And often aqua is called blue-green when in actuality the latter is cyan, and light cyan-green would be aqua. What adds to the confusion is that cyan LEDs are enclosed in blue plastic. A great amount of work is needed to dispel these intuitive myths of colour mixing before accurate descriptions of physical phenomena and their production can happen."
An article on LEDs is definitely NOT the place to post this sort of pedantic (and factually highly suspect) rant. Furthermore the definition of blue is readily recognized in the general public and the above paragraph merely serves to convolute the issue.-- Deglr6328 04:13, 13 Nov 2004 (UTC)
The page lists the one in times square at 118 feet. However the one on the Fremont Street Experience is over 1,500 feet long so it would seem that one is larger. For details on the display look at [1] for the size information look at [2]
Anyone care to address the differences in the light output profiles? Some types of lighting are better for human eyes than others...
~ender 2005-04-16 11:00:MST
Diffuse light is always the best for all animals, even plants, because of the envinronment where they have developed for millions of years. Collimated light is an artifice created by humans to save energy. This is why Leds are best for displays, and lasers for transmission. Of course, applications are many and every case requires analysis, but this is a general feature of the distinct light sources.
It seems that this article is mostly about through-hole LEDs. I think this should be altered so that this page is more about the LED chips and their technology generally, with more specific articles to talk about the various modes of packaging: T1, T1-3/4, the Luxeon technology, various surface mount packages, the large arrays produced by Lamina Ceramics, etc.
we need a close-up diagram that shows the internal structure, like [4], [5], [6], [7] but better. Like the first one but more close-up would be ideal in my mind. - Omegatron 15:05, Jun 8, 2005 (UTC)
What is the life span of an LED light? Is it true that they last "forever", or are the people who market this saying that if not used continuously, they seem to last forever?
Also, what is the maximum and minimum size of an individual LED?
I didn't seem to find answers to these questions in the article -- they should be included.
[8] This accidental discovery may replace light bulbs. Simesa 18:43, 22 October 2005 (UTC)
This article needs to be reorganized. It just doesn't make much sense, it doesn't have a logical flow. Also, it should have some statistics, like how long they last, what their efficiency is, how bright they generally are and how bright the brightest are. And you shouldn't have to sift through the whole article to find the information (like you currently do with the efficiency). Twilight Realm 02:23, 3 November 2005 (UTC)
The Inquirer reports another approach to generating white light: purple LED with a silicon carbide substrate, developed by Professor Satoshi Kamiyama of the Meijo University and producing 130 lm/W
I think the White LED section should be separated from any blue LED section, as many of the alternative approaches don't use blue LED's.
Skierpage 05:22, 17 November 2005 (UTC)
I've reverted out the butterfly wing "analogue" since I doubt it would be useful to a reader trying to learn about LEDs. Just because Wikipedia is much less limited in space than a paper encyclopedia doesn't relieve us of the necessity to be on-topic and concise - we can't drag in every peripheral reference or notion. -- Wtshymanski 14:36, 18 November 2005 (UTC)
The article says ...and situations where dark adaptation (night vision) must be preserved, such as cockpit and bridge illumination, observatories, etc. Yellow LED lights are a good choice to meet these special requirements because the human eye is more sensitive to yellow light.... Usually red light is used in these circumstances, not because the eye is more sensitive but because the eye's night-vision mechanism is less sensitive at these wavelengths so not harmed by the light. EdDavies 18:03, 2 December 2005 (UTC)
Any of you guys seen the new LUXEON LED flashlights yet ? I have two of these, both sold in the SEARS franchise, both are CRAFTSMAN. These are WHITE LEDS w/ NO other color in them at all. Other companies make these lights as well. Martial Law 07:27, 7 March 2006 (UTC) :)
It seems LED's would be ideal for computer displays. Energy consumption would depend only on the average brightness of each pixel being displayed and black would be pure black, unlike today's LCD's. Also response time would be orders om magnitude better than LCD's. I see that there are plenty of large LED displays, but not small ones, so I assume they cannot be minaturized enough to be made into a high resolution device like a PC display. TimL 21:06, 19 March 2006 (UTC)
While the applications section talks about LEDs in traffic signals, it doesn't talk about their application in cars. Cars with LED stop lights and indicators are now common and their advantages, particularly quick illumination, are well advertised. Could somebody add this in?
Some manufacturers have also shown LED headlights at various automotive shows, I believe. Bicycle lights are also commonly LED.
http://www.electronicsweekly.com/Article4455.htm
OK, for you experts that believe LEDs do not give off heat, please check out the DOE website on SSL (Solid State Lighting). http://www.netl.doe.gov/ssl/ and this article dated December 2006 http://www.netl.doe.gov/ssl/PDFs/CPTP%20Pilot%20Testing%20Results%20Summary--draft-12-06-06.pdf Danpeddle 00:49, 21 February 2007 (UTC)
The Vietnamese link is Luxeon, which although relevant, is not exactly a synonym of LED. Somebody should correct it. Wek1 19:47, 8 April 2006 (UTC)
I removed the branchlist template. I did not see how most of the links in there had anything to do with LED's. Wouldn't be so bad if it wasn't right there at the top. I messed up the edit comment, so this is it. TimL 20:27, 10 April 2006 (UTC)
I may have made a unintentional mess w/ the Luxeon reference. Can someone straighten this out ? Martial Law 21:51, 22 April 2006 (UTC) :)
No problem, I removed it. TimL 00:40, 23 April 2006 (UTC)
P.S. Just about any light will blind you if you stare directly into them long enough. TimL 00:42, 23 April 2006 (UTC)
It should merit a mention that blue LEDs are no longer "fashionable", but rather categorized as one of the more serious crimes against humanity. Chinese manufacturers have a fancy to put blue leds on any possible device in any possible position and their brightness is so high it drives people mad. Here in Hungary there is actually a movement for the ban and destruction of blue LEDs. Blue leds are probably the most evil use of quantum mechanics ever known to man and certainly a crux of bad taste.
quote: "This blue LED madness has to stop. Altec Lansing, with their FX6021 Speaker System is only one of the manufacturers guilty of falling victim to this abominable trend, but the degree to which they’ve fallen for it is worse than most. The control pod’s power LED alone lights up a room at night, and with one or two volume LEDs illuminated, the overall brightness becomes uncomfortable. If you’re sending a very low-level audio signal into the system and have to keep it turned up to maximum volume, you’ll have six of these brilliant LEDs turning your ceiling into Rave Central, making it difficult to sleep if you’re facing the system."
The second paragraph in Multi-Touch Sensing is questionable. My understanding of it is as follows: LEDs emit light on fingers or stylus; then LEDs are switched off and receive THE SAME light reflected from fingers or stylus. It is impossible (or at least impractical) to build such a system, because light will travel to the fingers and back in a fraction of nanosecond while indicator LEDs used in matricies are not that fast (not to mention wiring delays and microprocessor timing).
I didn't find any info supporting abovementioned explanaition neither in the paper by Dietz, Yerazunis nor on the Jeff Han's page.
I think LED matricies are used as touch-sensitive devices a little different way, for example even and odd matrix rows can be switched on and off in turns, and the light from even rows, reflected from user's fingers, is detected by odd rows and vice versa. -- Ilkuch 08:02, 30 June 2006 (UTC)
Does anyone know of a major corporation that sells LED lights? I know you can buy them off the internet [10] but I would prefer to buy them in a store. Like does Walmart or some of place like that sell a bag of 100 of them? Thanks. sharp dust 18:05, 21 July 2006 (UTC) (a beginner to LED lights)
Should Bicolor and/or tricolor leds have their own separate page(s)? There is only a small mention of them on the led page. Pi.1415926535 17:06, 27 August 2006
Did anyone else notice the article in the PlanetAnalog insert in EETimes magazine on Aug 28, 2006, by Karl Schlossstein? The title was "LED's diverse advances lead to numerous possibilities". Unfortunately I can't find an online version of the article --- I only have the paper version.
At least three sentences seem to be "borrowed" from this article.
Schlossstein | Wikipedia |
---|---|
"Gallium nitride (GaN) and indium gallium nitride (InGaN) blue LEDs enabled white LEDs by adding a combination of red and green LEDs or by covering the blue LED with a yellowish Ce3+:YAG (cerium-doped yttrium aluminum garnet) phosphor, the most common technique today." | "Most 'white' LEDs in production today use a ... GaN (gallium nitride) or InGaN (indium gallium nitride) LED covered by a yellowish phosphor coating usually made of cerium-doped yttrium aluminum garnet (Ce3+:YAG) crystals..." |
"New methods of creating white light from LEDs use no phosphors... One method uses a homoepitaxially grown zinc selenide (ZnSe) on a zinc selenides substrate to produce a blue light from the active region and a yellow light from the substrate at the same time." | "The newest method used to produce white light LEDs uses no phosphors at all and is based on homoepitaxially grown zinc selenide (ZnSe) on a ZnSe substrate which simultaneously emits blue light from its active region and yellow light from the substrate." |
"Michael Bowers, a grad student at Vanderbilt University...found that blue light caused his quantum dots to emit a white light simlar to an incandescent bulb." | "A new technique just developed by Michael Bowers, a graduate student at Vanderbilt University in Nashville, involves coating a blue LED with quantum dots that glow white in response to the blue light from the LED. This technique produces a warm, yellowish-white light similar to that produced by incandescent bulbs." |
Schlossstein has done some notable copyediting, improving the flow of these sentences, and adapted them to the rest of his article. He's also located sources for some statements that are presented in Wikipedia with no citation. But it looks to me as if his article skates close to the edge of plagiarizing Wikipedia, and he gives no credit to this site. If you agree with this judgement, consider letting the editors of PlanetAnalog and EE Times, and Schlossstein's employers (he's an applications engineer at National Semi) know what you think.
-- The Photon 03:54, 4 September 2006 (UTC)
an Led can explode if there is no resistor on it.
i added a little information to disadvantages of leds. i said they explode without a resistor —The preceding unsigned comment was added by Atlfalcons866 ( talk • contribs) .
LEDs exploding is a known problem with IR LED therapy. A safety screen must be used.
Tabby (
talk)
06:08, 24 January 2008 (UTC)
Should we sort the list of applications somehow. I just added one and I had no clue where to put it in the existing list. ForestJay 17:29, 13 September 2006 (UTC)
I really don't understand what is thought to be so special about LEDs with a chip in them that makes them periodically flash. Honestly, why is this news. you can make almost any other electronic light source do the same thing by adding flashing circutry. big deal. It tells the reader nothing fundamental about how an LED actually operates and produces light and does not belong in the physical function section. Can't we at least move it to the LED advantages section?-- Deglr6328 19:04, 21 September 2006 (UTC)
The higher efficiency and life expectancy of LEDs in comparison to the common light bulb or possibly even the neon tube should result in lower cost over their life span. To look at cost in lumens per dollar tells about upfront cost but not overall cost.
I could calculate that properly but I would need more appropriate data. Can anybody help with that? Walter Hartmann 23:18, 13 October 2006 (UTC)
What is that LED with three leads in the picture that has a whole bunch of LEDs? Why does it have three? Is it one of those bicolor ones or something? Someone should put that in the picture description. Thanks. Ilikefood 20:41, 20 October 2006 (UTC)
one part says that LEDs are more cost-efficiant than regular lights, while another part says that they're less efficient. Which one is correct? Ilikefood 22:12, 30 October 2006 (UTC)
LED history goes back a long time. Next year, 2007, it will be 100 years old. However, I am not a historian and leave to this group to debate. I do think history and dates are important for any reference document. Here is a link from the Cambridge University Press http://www.deastore.com/pdf/cambridge_03302006_093610/0521823307_excerpt.pdf I've also read about this in other electronic magazines or journals, which is why I looked for a document online. Danpeddle 03:50, 15 December 2006 (UTC)
In 1962, Nick Holonyak Jr. of General Electric did not invent the first practical visible LED. He was the first to construct a visible-spectrum semiconductor laser. For this work he is considered the inventor of the first practical LED, the red GaAs1-xPx LED. Ref; http://www.micro.uiuc.edu/ssdl/ Danpeddle 20:11, 23 December 2006 (UTC)
Why is there not a section on History? I read other components and they provide a history. Danpeddle 11:44, 26 December 2006 (UTC)
For reference, there is his citation when awarded the Japan Prize: [12]. There is also his article
{{
cite journal}}
: Check date values in: |date=
(
help),where he says, "The first practical visible-spectrum LED, GaAs1-xPx, came into existence in 1962 (based on work from 1960 to 1962) ..." (with citation to an article on the epitaxial growth technique, and US Patent 3 249 473 (Google link)). The attached biography of that article states, "His work from 1960 to 1962 on GaAsP ... led to the commercial introduction of GaAsP LEDs."
Hope this helps. -- The Photon 02:02, 30 December 2006 (UTC)
A recent article points out that a Russian scientist first described in an academic paper the principles behind the LED, back in the 1920's. See: [13] - maybe this could be used to update the article? User:Kena
I've added a photo with a caption stating that LED Christmas lights are becoming popular in "some North American cities", but can anyone back this up? I know they are extremely popular this year in Ottawa, but I haven't a clue if this popularity is only a local thing, a national thing, or something sparking (haha, pun) across the continent. Are LED X-mas lights popular where you live? Eiffelle 05:15, 24 December 2006 (UTC)
User Miwaya seems intent on removing all information in the article relating to Shuji Nakamura's invention of the blue led and replacing it with the "official Nichia" version of history where he is completely absent. No surprise considering they lost a 7 million dollar lawsuit from Nakamura. In any case Miwaya (who has obviously begun sock puppeting as user "Maslinka" and who began these edits with an IP that traces to Nagoya Japan) refuses to discuss his edits and as long as he does so I will revert them out of hand as being bad faith and unsubstantiated.-- Deglr6328 09:45, 17 January 2007 (UTC)
Do you work for Nichia? Because that is the only possible way I could see someone taking such a statement a face value. Nichia, being sued by Nakamura at the time, obviously had a vested interest in claiming that he had nothing to do with the invention of the LED. I am not going to allow you to whitewash the led article of all information about Nakamura based on a press release. If you want to state that "Nichia claimes such and such in this press release" ON THE NICHIA PAGE, that's fine. It does not belong on the LED page. Please place all further correspondence on the TALK page of the articles in question. Also see articles Wikipedia:Policies and guidelines and Wikipedia:Sock puppetry. -- Deglr6328 18:19, 17 January 2007 (UTC)
(copied from somewhere by user:Miwaya) You have presented no convincing evidence of the inventio of the blue led by any other person than nakamura. If you continue to add this bias misinformation to the led article I will initiate a request for comment.-- Deglr6328 03:18, 20 January 2007 (UTC)
SIGN your edits! User Miwaya continues to add the erroneous information about Isamu Akasaki "inventing the blue led" based on Mg doped GaN. This is no more true than claiming that Herb Maruska, the man who first observed violet electroluminescence from an Mg doped GaN crystal in 1972 invented the blue led. Isamu Akasaki's discovery of annealed Mg doped GaN no more resulted in a commercial blue led than did Maruska's. Efficient blue GaN emitters were developed by Shuji Nakamura's invention of the InGaN/AlGaN double heterostructure system. [19] No one attributes the invention of the blue led to either Maruska or Akasaki except you, wikipedia is not the place to push your agenda. STOP REMOVING THIS INFORMATION FROM THE ARTICLE. -- Deglr6328 08:20, 20 January 2007 (UTC)
Listed at RfC http://en.wikipedia.org/wiki/Wikipedia:Requests_for_comment/Maths%2C_science%2C_and_technology#Technology_and_engineering -- Deglr6328 08:29, 20 January 2007 (UTC)
I'm afraid you are up against a nearly complete worldwide consensous of Nakamura inventing the blue LED, not Akasaki and you are going to need a better source than a press release from Nichia saying otherwise. -- Deglr6328 19:38, 20 January 2007 (UTC)
![]() | This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 | Archive 2 | Archive 3 | Archive 4 |
Can anyone provide evidence that infrared laser diodes are used in remote controls? A quick scan of the laser diode article and the remote control article doesn't seem to support this wording. The remote for my VCR, for example, does use an infrared diode, but certainly doesn't use an infrared laser diode to lase and emit an infrared laser beam - that would mean you'd have to point it RIGHT at the remote sensor for the signal to be received.
If someone can justify leaving the "infrared laser diode" entry in the applications section, reply here, but otherwise I'll change it to read "infrared diode" instead.
Abqwildcat 18:18, 28 May 2004 (UTC)
Actually, the issue of the beam opening depends also on the coupling between the emitting device and the air, so you could potentially have a laser source with a wider spread. But cost is the main factor of choice.[islay16years]
Actually, I believe diode lasers generally have a pretty darn awful angle of divergence and without a collimator lens they don't create anything close to a beam. But despite the zoomy name, their output power isn't much different from that of an IR LED (if not inferior). They're easily fried and require a monitoring circuit, and at maybe 100 times the cost I can't think of a single reason why one would use a laser in a remote. Typical IR LEDs are available with 'angles of half intensity' ranging from ±10° to ±60°. Remote LEDs are driven with short but intense bursts of current and the driver circuit may become tricky (read: half a cent more). A narrower beam needs much less power for the same angular intensity than a wide beam that illuminates half the room. Guess which LED type gets chosen. Femto 11:27, 15 Dec 2004 (UTC)
I have noticed that if you own a camera with a "nightvision" mode, you are able to see the IR LED transmitting to the receiver. Turn all your lights off, turn nightvision on, and then press some buttons. I have tried this with many remote controls and they all do this. Therefore that leads me to believe that they are in fact regular LED's.
What is the proper terminology when referring to a light fixture that uses LED technology, would I call it an LED lamped fixture? reply to klewis@cncarley.com
So OLED LEDs are 10% efficient? What does that mean? How efficient are other types and colors? Can someone connect the dots between the percent efficiency and the lumens/watt? Omegatron 21:45, Feb 19, 2004 (UTC)
I cleaned up the section on OLEDs, which was unclear. I had to infer some of the information -- I'm not a domain expert. Care to verify I haven't introduced inaccuracies? --Anonymous
No one talk about Luxeon yet. :o). D@mn, I wish I have enough technical English to write an article about it.
Helloooooooooooo, any flashaholics/CPFer here?
There is a description of 1W and 5W LEDs near the end of LED technology section. It does not mention Luxeon by name; there are other manufacturers of high-power LEDs.
From the SI article:
Similarly it is ' candela' not 'candelas', ' metre' not 'metres' or 'meters'. 213.51.209.230 11:29, 9 Oct 2004 (UTC)
Ooops. Confusion arising, very simple. Technically 60 W, or 60 Watt lamp. No problem. In common language (anywhere) one has: "I was 3 meters away from him, and I could not hit him with a 2 meter (2 m) rod". End of story.
I removed a dispute tag (no actual dispute ever existed so far as I can see) and the following paragraph:
"The above list is taken from public sources, but at least one LED given as blue does not produce blue light. (There is a good chance that almost none do, because of the higher frequency of blue.) This is a common problem in daily life due to the majority of mankind being ignorant of colour theory and conflating blue with light blue with cyan, the latter often called "sky blue". A cyan LED may be distinguished from a blue LED in that adding a yellow phosphor to the output makes green, rather than white light. And often aqua is called blue-green when in actuality the latter is cyan, and light cyan-green would be aqua. What adds to the confusion is that cyan LEDs are enclosed in blue plastic. A great amount of work is needed to dispel these intuitive myths of colour mixing before accurate descriptions of physical phenomena and their production can happen."
An article on LEDs is definitely NOT the place to post this sort of pedantic (and factually highly suspect) rant. Furthermore the definition of blue is readily recognized in the general public and the above paragraph merely serves to convolute the issue.-- Deglr6328 04:13, 13 Nov 2004 (UTC)
The page lists the one in times square at 118 feet. However the one on the Fremont Street Experience is over 1,500 feet long so it would seem that one is larger. For details on the display look at [1] for the size information look at [2]
Anyone care to address the differences in the light output profiles? Some types of lighting are better for human eyes than others...
~ender 2005-04-16 11:00:MST
Diffuse light is always the best for all animals, even plants, because of the envinronment where they have developed for millions of years. Collimated light is an artifice created by humans to save energy. This is why Leds are best for displays, and lasers for transmission. Of course, applications are many and every case requires analysis, but this is a general feature of the distinct light sources.
It seems that this article is mostly about through-hole LEDs. I think this should be altered so that this page is more about the LED chips and their technology generally, with more specific articles to talk about the various modes of packaging: T1, T1-3/4, the Luxeon technology, various surface mount packages, the large arrays produced by Lamina Ceramics, etc.
we need a close-up diagram that shows the internal structure, like [4], [5], [6], [7] but better. Like the first one but more close-up would be ideal in my mind. - Omegatron 15:05, Jun 8, 2005 (UTC)
What is the life span of an LED light? Is it true that they last "forever", or are the people who market this saying that if not used continuously, they seem to last forever?
Also, what is the maximum and minimum size of an individual LED?
I didn't seem to find answers to these questions in the article -- they should be included.
[8] This accidental discovery may replace light bulbs. Simesa 18:43, 22 October 2005 (UTC)
This article needs to be reorganized. It just doesn't make much sense, it doesn't have a logical flow. Also, it should have some statistics, like how long they last, what their efficiency is, how bright they generally are and how bright the brightest are. And you shouldn't have to sift through the whole article to find the information (like you currently do with the efficiency). Twilight Realm 02:23, 3 November 2005 (UTC)
The Inquirer reports another approach to generating white light: purple LED with a silicon carbide substrate, developed by Professor Satoshi Kamiyama of the Meijo University and producing 130 lm/W
I think the White LED section should be separated from any blue LED section, as many of the alternative approaches don't use blue LED's.
Skierpage 05:22, 17 November 2005 (UTC)
I've reverted out the butterfly wing "analogue" since I doubt it would be useful to a reader trying to learn about LEDs. Just because Wikipedia is much less limited in space than a paper encyclopedia doesn't relieve us of the necessity to be on-topic and concise - we can't drag in every peripheral reference or notion. -- Wtshymanski 14:36, 18 November 2005 (UTC)
The article says ...and situations where dark adaptation (night vision) must be preserved, such as cockpit and bridge illumination, observatories, etc. Yellow LED lights are a good choice to meet these special requirements because the human eye is more sensitive to yellow light.... Usually red light is used in these circumstances, not because the eye is more sensitive but because the eye's night-vision mechanism is less sensitive at these wavelengths so not harmed by the light. EdDavies 18:03, 2 December 2005 (UTC)
Any of you guys seen the new LUXEON LED flashlights yet ? I have two of these, both sold in the SEARS franchise, both are CRAFTSMAN. These are WHITE LEDS w/ NO other color in them at all. Other companies make these lights as well. Martial Law 07:27, 7 March 2006 (UTC) :)
It seems LED's would be ideal for computer displays. Energy consumption would depend only on the average brightness of each pixel being displayed and black would be pure black, unlike today's LCD's. Also response time would be orders om magnitude better than LCD's. I see that there are plenty of large LED displays, but not small ones, so I assume they cannot be minaturized enough to be made into a high resolution device like a PC display. TimL 21:06, 19 March 2006 (UTC)
While the applications section talks about LEDs in traffic signals, it doesn't talk about their application in cars. Cars with LED stop lights and indicators are now common and their advantages, particularly quick illumination, are well advertised. Could somebody add this in?
Some manufacturers have also shown LED headlights at various automotive shows, I believe. Bicycle lights are also commonly LED.
http://www.electronicsweekly.com/Article4455.htm
OK, for you experts that believe LEDs do not give off heat, please check out the DOE website on SSL (Solid State Lighting). http://www.netl.doe.gov/ssl/ and this article dated December 2006 http://www.netl.doe.gov/ssl/PDFs/CPTP%20Pilot%20Testing%20Results%20Summary--draft-12-06-06.pdf Danpeddle 00:49, 21 February 2007 (UTC)
The Vietnamese link is Luxeon, which although relevant, is not exactly a synonym of LED. Somebody should correct it. Wek1 19:47, 8 April 2006 (UTC)
I removed the branchlist template. I did not see how most of the links in there had anything to do with LED's. Wouldn't be so bad if it wasn't right there at the top. I messed up the edit comment, so this is it. TimL 20:27, 10 April 2006 (UTC)
I may have made a unintentional mess w/ the Luxeon reference. Can someone straighten this out ? Martial Law 21:51, 22 April 2006 (UTC) :)
No problem, I removed it. TimL 00:40, 23 April 2006 (UTC)
P.S. Just about any light will blind you if you stare directly into them long enough. TimL 00:42, 23 April 2006 (UTC)
It should merit a mention that blue LEDs are no longer "fashionable", but rather categorized as one of the more serious crimes against humanity. Chinese manufacturers have a fancy to put blue leds on any possible device in any possible position and their brightness is so high it drives people mad. Here in Hungary there is actually a movement for the ban and destruction of blue LEDs. Blue leds are probably the most evil use of quantum mechanics ever known to man and certainly a crux of bad taste.
quote: "This blue LED madness has to stop. Altec Lansing, with their FX6021 Speaker System is only one of the manufacturers guilty of falling victim to this abominable trend, but the degree to which they’ve fallen for it is worse than most. The control pod’s power LED alone lights up a room at night, and with one or two volume LEDs illuminated, the overall brightness becomes uncomfortable. If you’re sending a very low-level audio signal into the system and have to keep it turned up to maximum volume, you’ll have six of these brilliant LEDs turning your ceiling into Rave Central, making it difficult to sleep if you’re facing the system."
The second paragraph in Multi-Touch Sensing is questionable. My understanding of it is as follows: LEDs emit light on fingers or stylus; then LEDs are switched off and receive THE SAME light reflected from fingers or stylus. It is impossible (or at least impractical) to build such a system, because light will travel to the fingers and back in a fraction of nanosecond while indicator LEDs used in matricies are not that fast (not to mention wiring delays and microprocessor timing).
I didn't find any info supporting abovementioned explanaition neither in the paper by Dietz, Yerazunis nor on the Jeff Han's page.
I think LED matricies are used as touch-sensitive devices a little different way, for example even and odd matrix rows can be switched on and off in turns, and the light from even rows, reflected from user's fingers, is detected by odd rows and vice versa. -- Ilkuch 08:02, 30 June 2006 (UTC)
Does anyone know of a major corporation that sells LED lights? I know you can buy them off the internet [10] but I would prefer to buy them in a store. Like does Walmart or some of place like that sell a bag of 100 of them? Thanks. sharp dust 18:05, 21 July 2006 (UTC) (a beginner to LED lights)
Should Bicolor and/or tricolor leds have their own separate page(s)? There is only a small mention of them on the led page. Pi.1415926535 17:06, 27 August 2006
Did anyone else notice the article in the PlanetAnalog insert in EETimes magazine on Aug 28, 2006, by Karl Schlossstein? The title was "LED's diverse advances lead to numerous possibilities". Unfortunately I can't find an online version of the article --- I only have the paper version.
At least three sentences seem to be "borrowed" from this article.
Schlossstein | Wikipedia |
---|---|
"Gallium nitride (GaN) and indium gallium nitride (InGaN) blue LEDs enabled white LEDs by adding a combination of red and green LEDs or by covering the blue LED with a yellowish Ce3+:YAG (cerium-doped yttrium aluminum garnet) phosphor, the most common technique today." | "Most 'white' LEDs in production today use a ... GaN (gallium nitride) or InGaN (indium gallium nitride) LED covered by a yellowish phosphor coating usually made of cerium-doped yttrium aluminum garnet (Ce3+:YAG) crystals..." |
"New methods of creating white light from LEDs use no phosphors... One method uses a homoepitaxially grown zinc selenide (ZnSe) on a zinc selenides substrate to produce a blue light from the active region and a yellow light from the substrate at the same time." | "The newest method used to produce white light LEDs uses no phosphors at all and is based on homoepitaxially grown zinc selenide (ZnSe) on a ZnSe substrate which simultaneously emits blue light from its active region and yellow light from the substrate." |
"Michael Bowers, a grad student at Vanderbilt University...found that blue light caused his quantum dots to emit a white light simlar to an incandescent bulb." | "A new technique just developed by Michael Bowers, a graduate student at Vanderbilt University in Nashville, involves coating a blue LED with quantum dots that glow white in response to the blue light from the LED. This technique produces a warm, yellowish-white light similar to that produced by incandescent bulbs." |
Schlossstein has done some notable copyediting, improving the flow of these sentences, and adapted them to the rest of his article. He's also located sources for some statements that are presented in Wikipedia with no citation. But it looks to me as if his article skates close to the edge of plagiarizing Wikipedia, and he gives no credit to this site. If you agree with this judgement, consider letting the editors of PlanetAnalog and EE Times, and Schlossstein's employers (he's an applications engineer at National Semi) know what you think.
-- The Photon 03:54, 4 September 2006 (UTC)
an Led can explode if there is no resistor on it.
i added a little information to disadvantages of leds. i said they explode without a resistor —The preceding unsigned comment was added by Atlfalcons866 ( talk • contribs) .
LEDs exploding is a known problem with IR LED therapy. A safety screen must be used.
Tabby (
talk)
06:08, 24 January 2008 (UTC)
Should we sort the list of applications somehow. I just added one and I had no clue where to put it in the existing list. ForestJay 17:29, 13 September 2006 (UTC)
I really don't understand what is thought to be so special about LEDs with a chip in them that makes them periodically flash. Honestly, why is this news. you can make almost any other electronic light source do the same thing by adding flashing circutry. big deal. It tells the reader nothing fundamental about how an LED actually operates and produces light and does not belong in the physical function section. Can't we at least move it to the LED advantages section?-- Deglr6328 19:04, 21 September 2006 (UTC)
The higher efficiency and life expectancy of LEDs in comparison to the common light bulb or possibly even the neon tube should result in lower cost over their life span. To look at cost in lumens per dollar tells about upfront cost but not overall cost.
I could calculate that properly but I would need more appropriate data. Can anybody help with that? Walter Hartmann 23:18, 13 October 2006 (UTC)
What is that LED with three leads in the picture that has a whole bunch of LEDs? Why does it have three? Is it one of those bicolor ones or something? Someone should put that in the picture description. Thanks. Ilikefood 20:41, 20 October 2006 (UTC)
one part says that LEDs are more cost-efficiant than regular lights, while another part says that they're less efficient. Which one is correct? Ilikefood 22:12, 30 October 2006 (UTC)
LED history goes back a long time. Next year, 2007, it will be 100 years old. However, I am not a historian and leave to this group to debate. I do think history and dates are important for any reference document. Here is a link from the Cambridge University Press http://www.deastore.com/pdf/cambridge_03302006_093610/0521823307_excerpt.pdf I've also read about this in other electronic magazines or journals, which is why I looked for a document online. Danpeddle 03:50, 15 December 2006 (UTC)
In 1962, Nick Holonyak Jr. of General Electric did not invent the first practical visible LED. He was the first to construct a visible-spectrum semiconductor laser. For this work he is considered the inventor of the first practical LED, the red GaAs1-xPx LED. Ref; http://www.micro.uiuc.edu/ssdl/ Danpeddle 20:11, 23 December 2006 (UTC)
Why is there not a section on History? I read other components and they provide a history. Danpeddle 11:44, 26 December 2006 (UTC)
For reference, there is his citation when awarded the Japan Prize: [12]. There is also his article
{{
cite journal}}
: Check date values in: |date=
(
help),where he says, "The first practical visible-spectrum LED, GaAs1-xPx, came into existence in 1962 (based on work from 1960 to 1962) ..." (with citation to an article on the epitaxial growth technique, and US Patent 3 249 473 (Google link)). The attached biography of that article states, "His work from 1960 to 1962 on GaAsP ... led to the commercial introduction of GaAsP LEDs."
Hope this helps. -- The Photon 02:02, 30 December 2006 (UTC)
A recent article points out that a Russian scientist first described in an academic paper the principles behind the LED, back in the 1920's. See: [13] - maybe this could be used to update the article? User:Kena
I've added a photo with a caption stating that LED Christmas lights are becoming popular in "some North American cities", but can anyone back this up? I know they are extremely popular this year in Ottawa, but I haven't a clue if this popularity is only a local thing, a national thing, or something sparking (haha, pun) across the continent. Are LED X-mas lights popular where you live? Eiffelle 05:15, 24 December 2006 (UTC)
User Miwaya seems intent on removing all information in the article relating to Shuji Nakamura's invention of the blue led and replacing it with the "official Nichia" version of history where he is completely absent. No surprise considering they lost a 7 million dollar lawsuit from Nakamura. In any case Miwaya (who has obviously begun sock puppeting as user "Maslinka" and who began these edits with an IP that traces to Nagoya Japan) refuses to discuss his edits and as long as he does so I will revert them out of hand as being bad faith and unsubstantiated.-- Deglr6328 09:45, 17 January 2007 (UTC)
Do you work for Nichia? Because that is the only possible way I could see someone taking such a statement a face value. Nichia, being sued by Nakamura at the time, obviously had a vested interest in claiming that he had nothing to do with the invention of the LED. I am not going to allow you to whitewash the led article of all information about Nakamura based on a press release. If you want to state that "Nichia claimes such and such in this press release" ON THE NICHIA PAGE, that's fine. It does not belong on the LED page. Please place all further correspondence on the TALK page of the articles in question. Also see articles Wikipedia:Policies and guidelines and Wikipedia:Sock puppetry. -- Deglr6328 18:19, 17 January 2007 (UTC)
(copied from somewhere by user:Miwaya) You have presented no convincing evidence of the inventio of the blue led by any other person than nakamura. If you continue to add this bias misinformation to the led article I will initiate a request for comment.-- Deglr6328 03:18, 20 January 2007 (UTC)
SIGN your edits! User Miwaya continues to add the erroneous information about Isamu Akasaki "inventing the blue led" based on Mg doped GaN. This is no more true than claiming that Herb Maruska, the man who first observed violet electroluminescence from an Mg doped GaN crystal in 1972 invented the blue led. Isamu Akasaki's discovery of annealed Mg doped GaN no more resulted in a commercial blue led than did Maruska's. Efficient blue GaN emitters were developed by Shuji Nakamura's invention of the InGaN/AlGaN double heterostructure system. [19] No one attributes the invention of the blue led to either Maruska or Akasaki except you, wikipedia is not the place to push your agenda. STOP REMOVING THIS INFORMATION FROM THE ARTICLE. -- Deglr6328 08:20, 20 January 2007 (UTC)
Listed at RfC http://en.wikipedia.org/wiki/Wikipedia:Requests_for_comment/Maths%2C_science%2C_and_technology#Technology_and_engineering -- Deglr6328 08:29, 20 January 2007 (UTC)
I'm afraid you are up against a nearly complete worldwide consensous of Nakamura inventing the blue LED, not Akasaki and you are going to need a better source than a press release from Nichia saying otherwise. -- Deglr6328 19:38, 20 January 2007 (UTC)