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History of the LED — the Movie 106

ptorrone writes "MAKE Magazine has a fantastic 'Connections'-style video called THE LED — The short documentary has the history of the LED to modern day applications. Starting with the work of Russian Oleg Vladimirovich Losev, which was largely ignored in the 1920s, to making your own 'Cat's Whisker' — a primitive LED made from a metal-semiconductor point-contact junction forming a Schottky barrier diode. The first practical visible-spectrum LED was developed in 1962 by Nick Holonyak Jr., while working at General Electric Company."
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History of the LED — the Movie

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  • by illumastorm ( 172101 ) on Sunday November 23, 2008 @05:36PM (#25867419)

    It was such an enlightening experience.

    • by inKubus ( 199753 )

      The LED Museum [] seriously will enlighten you. What a classic.

      The video was good, also.

      • The LED museum was great when the guy running it kept to the history and technology of LEDs. The last few years he "reviews" flashlights and assorted crap. His prose, coupled with the byzantine webdesign, is hardly worth the very few bits of knowledge contained in the site. He had a good thing going, but he blew it.
  • glad to see more selection in LED holiday lighting this year, the price premium is a bitch tho... but provides such a superior shine. anyways... where am i?
    • I've found the purely LED lighting to be reasonably priced, it's the SOLAR led fairy lights that are the killer.

      I have a pretty darn large garden with many large trees, I'd love to have them all twinkling, but don't want power cables running all over the place. Solar fairy lights would be the answer if they weren't $70AUD or so for a couple of hundred globes.

      Still, they are dropping, so, hopefully next year will be the year of a garden enveloped in light for no electrical cost.

  • by lessthanpi ( 1333061 ) on Sunday November 23, 2008 @05:39PM (#25867449) Homepage
    This movie is to diode for
    • by MarkRose ( 820682 ) on Sunday November 23, 2008 @06:09PM (#25867671) Homepage
      Like, you can only resist the current of electronics jokes until the intensity of desire becomes too much and you breakdown, right?
      • by TheRealMindChild ( 743925 ) on Sunday November 23, 2008 @06:39PM (#25867865) Homepage Journal
        Nonsense! Two atoms walk into a bar. The first says "I think I've lost an electron", and the second replies "Are you sure?", and the first one says "I'm positive"
        • Re: (Score:3, Funny)

          by syousef ( 465911 )

          Nonsense! Two atoms walk into a bar. The first says "I think I've lost an electron", and the second replies "Are you sure?", and the first one says "I'm positive"

          The other took a closer look, but the wave function collapsed and the electron reappeared.

          • The first atom said, "Thanks! What do I owe you?" The second said, "This one's on me. No charge!"
        • Re: (Score:3, Funny)

          by mudshark ( 19714 )
          You call that funny? It's just ionic.

          Thanks! I'll be here all week. Tip your servers and avoid the crab louie like the plague!
          • I'm not gonna tip my server, I'm afraid the power cable might come loose and I'd lose my really high uptime.

            And if the disk crashed I'd be really screwed, all my backups are on it.
  • by MichaelSmith ( 789609 ) on Sunday November 23, 2008 @05:39PM (#25867455) Homepage Journal
    Once when I was a very young geek I had an array of LEDs set up for some purpose. I accidently added 10V to the power supply due to a lack of attention and bad UI design. Every single LED burst. It smelt horrible and I got out of there fast. Switched off the power supply first though.
    • by MarkRose ( 820682 ) on Sunday November 23, 2008 @05:58PM (#25867599) Homepage
      I think someone swindled you. They obviously sold you SEDs: Smoke Emitting Diodes. I got taken several times myself as a kid. It took me a while before I figured out how to spot proper components that kept the magic smoke inside.
      • Re: (Score:3, Funny)

        It took me a while before I figured out how to spot proper components that kept the magic smoke inside.

        Yeah I tried resistors for that but they often became Smoke Emitting Resistors too.

        • One of my favourite tricks was making transistors sublimate. I was proficient lol
          • I learned two things in 4 years of Engineering: 1. You can't push on a rope. 2. Electronics run on smoke. If the smoke escapes, it won't work. Someone subsequently pointed out that Rule #1 needed modification: 1. You can't push on a rope - unless it's frozen.
    • ok, since you guys are electronics geeks, can you answer this question for me--if an LED is just a silicon carbide/gallium arsenide/etc. crystal with two electrodes attached, then why does it matter which way the current is flowing? it seemed like in the YouTube video he just arbitrarily clipped an electrode onto one end of the SiC crystal, and then randomly touched the needle to the crystal in different places to create light.

      in other words, what determines which end is the anode and which end is the catho

      • Re: (Score:2, Informative)

        by mysidia ( 191772 )

        Different points on the crystal have different electrical properties/conductivity.

        The fact that it generates light when the probe touches a point does not necessarily mean that the crystal itself is a diode.

        But certain points on the crystal may have diode-like properties. []

      • by HopeOS ( 74340 )
        Actually, diodes are typically made from two separate pieces of material that are joined. One side has a slight negative charge, the other positive. At the junction where they meet, the electrons rearrange across the boundary to balance out. This new arrangement leaves a "gap" where there are fewer electrons than are needed for current to freely cross.

        If the diode is wired up in the forward mode, then the voltage potential helps close the gap, and current flows.

        If the diode is wired up in the reverse mo
    • well, when i was young, i put a red led into the 230V mains. the head part of the led went off like a bullet and stuck 1 cm deep into the wall.

    • by HopeOS ( 74340 )
      When I was younger, I used the Radio Shack TI99-4/A power supplies to drive breadboard projects since they were readily available. One evening when I turned on the supply, the 555 on the breadboard exploded raining parts all over the dining room. My dad looked in, suggested I check my wiring. All the wires came up, and I rewired it meticulously. When I applied the power the second time, same result. A quick sanity check revealed that the power supply was outputting 25V on the 5V line. Made me wonder what ki
      • I think I convinced a 14 pin TTL package to explode once but it blew out through the belly and just made a scorch mark on the PCB.

        OTH seeing that you were using a breadboard maybe it took off under rocket power. Hmm that gets me thinking. 555s are pretty cheap you know.
    • Ah, you've been there too.

      I got my first LEDs from Radio Shack. The packaging specified 1.5V forward voltage, so I figured an AAA cell would be fine. Not.

      While Proust recalled his childhood through the taste of madeleines [], a true geek gets zapped back by the smell of smoking epoxy.

  • Baby Blues. (Score:4, Interesting)

    by Ostracus ( 1354233 ) on Sunday November 23, 2008 @05:43PM (#25867499) Journal

    Interesting. Thing I wonder is I remember when blue LEDS were difficult and expensive to produce. Now almost every piece of equipment I have has a blue LED on it.

    • by MarkRose ( 820682 ) on Sunday November 23, 2008 @06:14PM (#25867707) Homepage
      So in other words, you're saying... they came out of the blue?
    • Re: (Score:2, Insightful)

      by fxkr ( 1343139 )

      Blue LEDs have the highest intensity.

      Also, they look cool, and now they are affordable. I mean, you couldn't get them, now you can, therefore you do.

      • Re:Baby Blues. (Score:5, Informative)

        by Anpheus ( 908711 ) on Sunday November 23, 2008 @06:32PM (#25867825)

        Oh god please, don't say they look cool. If one more thing in my house has a blue LED I'm never going to be able to get a night's sleep ever again. The damn things are like portals into a strange neon blue hell.

        Electrical tape works wonders, though.

        • by fxkr ( 1343139 )

          Electrical tape works wonders, though.

          So does the 'off' switch...

          • Re: (Score:3, Interesting)

            by MarkRose ( 820682 )
            Except when some marketing genius decided to make the standby light a blue one...
            • At least it doesn't blink, like the power led on Dells in standby mode. What were they thinking?

              • by glindsey ( 73730 )

                At least it doesn't blink, like the power led on Dells in standby mode. What were they thinking?

                Oh, that's easy: "How can we rip off Apple's 'heartbeat' sleeping light, but make it more annoying?"

              • by Fumus ( 1258966 )
                My Samsung SyncMaster 226BW has a blinking blue light when on standby...
              • Most motherboards blink the power LED in sleep mode. However, there is normally a separate connection for a "sleep" LED, so it's fair to say they're too cheap to add one LED.
          • So does the 'off' switch...

            Interesting difference between the US and UK: while I was puttering around Scotland, I noticed that all electronic equipment had a real off switch - not just a mamby pamby standby switch. I like the idea of being able to turn stuff off for real, not just into 'save 10%' standby mode.

            The first instance I can remember of something not being 'off' when off was a TV back in the 70's (?) that was marketed as being 'instant on'. It must've kept all the filaments hot (or at least warm)

        • I prefer the soldering iron approach. :)
          30 seconds later no more lights.

          • by Anonymous Coward on Sunday November 23, 2008 @08:55PM (#25868761)

            I might try this sometime. Should I apply the soldering iron to the LED or the product designer?

          • That would tend to void your warranty. Best to design the product without the bright LEDs. However, blinky lights are one of the things that customers like when they buy a product at the store, so it looks like the problem is here to stay. If you've got a choice between the ZhangTai DVD player with colored lights, and the RonsonCo DVD player that is a slim gray box that sits unobtrusively out of the way, you're going to pick the blinky one every time, especially if it's $0.99 cheaper than anything else o
          • I have several hundred of those old pale yellowy/green LEDs that you really have to look at to see if it's on.

            If some gadget has a bright LED I replace it with one of those. No more glare for me!

        • My new alarm clock uses them to illuminate the display and it's been keeping me from getting to sleep at night. I think I've devised a way to deal with it though -- window tint the display!
          • My new alarm clock uses them to illuminate the display and it's been keeping me from getting to sleep at night.

            yeah, there's some research into this. Get a red clock. Apparently other colors screw with your melatonin levels because your evolutionary ancestors needed to be more weary of being eaten on nights with a full moon. It's been implicated in leukemia in children since melatonin also has an anti-cancer effect. How sound the theory is I don't know, but at least it helps me sleep better and putting

            • Really? Due to your UID I'll take this seriously. I bought the clock for it's durability (WHACK THE ALARM IN THE MORNING), but this worries me. I'll go get a new red clock, and then see about modifying the blue one to use a red led for normal illumination and switch to blue when the alarm sounds. Thanks!
            • That sounds worthy of further research. I don't have blue LEDs in my clock, but it's an ancient Radio Shack model (I keep it because of the battery backup) with the old-school blue electroluminescent display. It's not terribly bright on the lower setting, fortunately.
        • by arielCo ( 995647 )

          Maybe the source of your grief is not so much the blue hue as the intensity of the glow - the halo would contribute to the eeriness. Ever tried to tame them with something translucid, like window film or magic marker? You could also change the series resistor, if available.

          Then again, maybe I'm all wrong and there is something about blue light that stimulates us humans the wrong way.

          (if you see the above in an AC post, that was me by mistake)

        • Blue LED's do look cool. It's just that the collective mass of gadget designers have taken 'cool' and extrapolated it to mean 'must have fourteen per square inch of gadget'.

          • The problem is that they all seem to feel like they need to put the flashlight-bright blue LEDs in everything. I've seen red LEDs that are just as bright, but I generally don't see them used as status indicators, so why are blue LEDs different?

            • Because blue is a different wavelength of light, which appears a lot more intense to our eyes.

        • Amen. I sit in front of large RAIDs from time to time and these days the drives all have blue activity lights. It drives me crazy and irritates my eyes after a while. Far worse than the good old green and red LEDs.

    • They are still a few times more expensive to produce than the red ones. I guess they just look that much cooler? Also, we're talking about $.25 vs $.10, if there's one LED on the product, that's not a huge difference.
    • Blue LEDs have been around since the 70s but not common until the 90s. A couple Japanese researchers in the 80s developed a new method for growing GaN crystals which made blue LEDs brighter and less expensive.
    • Re:Baby Blues. (Score:4, Informative)

      by MidnightBrewer ( 97195 ) on Sunday November 23, 2008 @11:46PM (#25869747)

      Yep. A Japanese researcher, Nakamura, finally figured out how to do it and the company he worked for made a fortune overnight. He finally had to sue them for royalties, since the company was making bank and gave him a measly $200 to show their appreciation).

      He finally got a $190 million dollar settlement. The company actually made six times that in royalties, and the judge said that he was actually entitled to half, but Nakamura only asked for $190 million, so that's what he got. []

  • 'A History of Light and Lighting' [] (4.5 Billion BC to 2005...) makes no mention of Mr. Holonyak...perhaps someone needs to build a fire under Mr. Williams.
  • by colinmc151 ( 714382 ) on Sunday November 23, 2008 @06:50PM (#25867943) Homepage

    Overall a very good video, but there is a small flaw. The video incorrectly notes that Oleg Vladimirovich Losev was a scientist in Imperial Russia... While Oleg Vladimirovich Losev was born in Imperial Russia, by the time he was working on diodes, it was the Soviet Union.

    Other than that, an excellent video that only left we with the question, where do you get chunks of carborundum?

    • I don't know if the crystals are large enough, but most DIY stores carry carborundum grinding media. You can get some pretty good-sized chunks on a rotary sanding pad. Plus, there are mineral [] and radio [] shops online.
    • In Imperial Russia, Czar makes diode out of YOU!
  • by phage434 ( 824439 ) on Sunday November 23, 2008 @07:16PM (#25868121)
    Can't anyone keep the difference between silicon and silicone straight? Silicon: element, component of semiconductors (and some blue LEDs made from silicon carbide); Silicone: compound, used for breast implants
    • by maird ( 699535 )
      This being slashdot, the error is probably just wishful thinking!
    • silicone is not a single compound, there are many different silicones which are polymers containing silicon.

    • Guess which one geeks are more likely to get their hands on?

      BTW, silicone is used as a sealant and makes a good lubricant, too. You know, for hinges and stuff. Yeah... hinges.

  • It's nice to be reminded that making shows like these actually take some talent, experience and skill. Decent programs require actors who can deliver the lines convincingly (and sympathetically), script writers who understand the difference between first and third person perspective, and editors that can figure out how to make the different camera angles show us what's being talked about, instead of what's happening somewhere else.

    What am I saying? Production values on this are just bad enough, it remin
  • Risky Business (Score:2, Insightful)

    by arachnoid ( 873176 )

    It's too bad the narrator tried to demonstrate his circuit-design skills. Near the end of the video he powers an LED by connecting it directly across a disc battery. The only reason he didn't burn up his LED is because the voltages and temperatures were just right, but even that lucky break might have evaporated over a matter of minutes as the LED warmed up. When operating LEDs, you always want to have a current-limiting resistor or circuit in place -- always. The reason is that an LED's voltage/current/tem

    • by nwf ( 25607 )

      I read that you should consider the internal resistance of the battery, which as I recall, was rather high in those coin-size batteries.

    • The only time I've ever had an LED go out on me without a resistor was when I was little and put one on a 9V.
    • If you finish watching the movie, he actually goes on to say exactly that, and shows how to properly wire it with a resistor.

    • by rdnetto ( 955205 )

      The reason is that an LED's voltage/current/temperature relationship contradicts naive assumptions about electrical conductors.

      To be specific, its that while a resistor will have a potential difference (voltage) proportional to the supply voltage, an LED's potential will never exceed a fixed voltage (IIRC its 1.5 V). Once the voltage exceeds this, you basically have a short circuit.

    • by mspohr ( 589790 )
      It's actually very safe to put a blue or white LED directly across a 3 volt battery. If you look at a graph of these diodes voltage versus light output, it's fairly linear in the area of 3 volts. The voltage drop across the diode is 3 volts so you don't need a resistor. It's not until you get above 4 volts that you get into the smoke generation range.
    • by Dahan ( 130247 )
      The Photon Micro-Light [] series of keychain LED flashlights have the LED connected straight to a lithium coin cell battery or two. Mine uses a pair of CR2016s, and has worked fine for years. You need to take into consideration the resistance of the battery.
    • by Alioth ( 221270 )

      The battery *is* the current limiting resistor. Those little coin batteries have high internal resistances, and are often used to power LEDs without resistors because of this.

      Even then, limiting current needn't be done with a resistor, in fact, the last thing you want for high power LEDs is a resistor because the resistor will waste tremendous amounts of energy. Instead, for power illuminators you want a current source (as opposed to a voltage source). There are ICs available to do this, you set the current

  • by tkohler ( 806572 ) on Monday November 24, 2008 @02:13AM (#25870395)
    If by "Connections-like" you mean appeals to nerds and involves history of technology, fine, but that is where the similarity ends. That being said, this was worth watching. The Silicon Carbide trick was cool.
  • Back in the day, Philips had the slogan "Let's make things better" [].
    However, some of my friends working at the Lighting Division changed that to "LED's make things better" :-)
  • by catmistake ( 814204 ) on Monday November 24, 2008 @04:04AM (#25870761) Journal

    Neat video. But each Connections episode starts with some piece of technology, and traces it back to its almost surprising and seemingly unrelated origins. This starts with the LED... and traces back to the origins of the LED. No fantastic and surprising connections there. About the only true similarities I see is that The LED narrator and James Burke apparently share the same hairstylist and optomitrist.

  • So they didn't go back to the real beginning, which was the publishing by H. J. Round of the discovery that a silicon crystal would emit light when a current was passed through it? The credit for first discovery needs to go to an Englishman, not a Soviet... []

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