50th anniversary of the LED + 2 days

Yep, it was first demonstrated on October 9, 1962 by Nick Holonyak, Jr., an employee of General Electric.  As Wired notes,

In the early 1960s, the only light emitted from LEDs was infrared. The race to produce a visible LED had GE researchers scrambling to be first.

Holonyak suggested using a mixture of gallium arsenide and gallium phosphide (GaAs phosphide). His fellow scientists said the mixture would not work. In fact, they were pretty vocal in their disagreement with Holonyak’s hypothesis.

“You so and so, if you would have been a chemist, you would have known that wouldn’t work and all that,” Holonyak told the producers of A Brilliant Idea: Nick Holonyak, Jr. and the LED, a video about his colleagues’ lack of faith in his idea.

Undeterred, Holonyak forged head and created a GaAs phosphide crystal. Fifty years ago today, he presented the first visible LED to GE executives. His mixture created a red glow that’s still seen today. But Holonyak believed that the dim glow of his invention was just the beginning.

Holonyak thought LEDs would replace incandescent bulbs, and they may still, for they’re already in flashlights.  We’re in a fluorescent-light phase now, but I suspect Holonyak will be proved right.

Here’s a short video featuring the still-extant inventor, and the longer film, with the link given above (I can’t embed it), is worth watching if you have 23 minutes to spare.  You should, because you use LEDs every day.


  1. Posted October 11, 2012 at 7:10 am | Permalink

    “Holonyak thought LEDs would replace incandescent bulbs, and they may still…”

    Indeed! Some firms are working on just that. For reasons I can’t go into, I just came across privately held Danish start-up Wave27 today:

    We are developing a 60W Edison incandescent lamp (E27) replacement using a 10W LED light source. It will have the same shape, the same light and thyristor dimming to ensure the full benefit of the right light in all those millions of lamp reflectors on desks, over dinner tables, in meeting-rooms and hallways, that we rely on every day.

    See the Target page for more about the benefits of this technology.

    My son, an engineering student, is a big advocate of this application of LEDs.


    • Reginald Selkirk
      Posted October 11, 2012 at 9:38 am | Permalink

      and thyristor dimming to ensure the full benefit of the right light in all those millions of lamp reflectors..

      LEDs are actually much better for dimming than either incandescents and fluorescents. But it is best done in a different way (PWM). The only reason to make it work with thyristors is for backwards compatibility. Once we accept that LEDs are the light of the future, we can start designing dimming circuits that work well with them, and the world will be a better place.

      A good dimming solution offers efficiency, convenience and reproducibility, and avoids colour shifting.

  2. peter
    Posted October 11, 2012 at 7:17 am | Permalink

    I recently renovated a kitchen, and put in all LEDs, quite a few. They cost more (which could be a lot more if you buy the wrong place), but despite that and the fact that electricity is cheaper here than most places, it will take only about 20 months to recover the difference in price. One possible but unlikely problem is if they burn out much earlier than predicted (many compact fluorescence bulbs did), but it seems unlikely, and no problems with more than 20 bulbs in the first 6 months. These are rated to use about 7 times less electricity than incandescent, using the warm white colour.

    • Philip
      Posted October 11, 2012 at 7:55 am | Permalink

      Recently did the same. Six LEDs light the whole kitchen, even when dimmed. Nice warm white light.

    • Posted October 11, 2012 at 2:44 pm | Permalink

      I have two mains-powered LED bulbs. The first, of 8 watts I got for a hallway where there are two prints I value (copies of watercolours of the vanished Pink and White Terraces by J C Hoyte, but it’s equivalent to about 100 watts, way too bright and rather cold for a hallway. It’s also dimmable, and cost [$US14], so I changed it for a 5 watt warmer non-dimmable [$US9]. The boxes say they have no UV or IR, but I’m wondering if their visible light will fade my prints. In the meantime I shade the fixture in their direction.

      • Posted October 11, 2012 at 3:19 pm | Permalink

        If the art is behind glass, then I wouldn’t even pretend to worry: glass is quite opaque to UV. And IR radiation just warms things up; it generally doesn’t cause any sort of damage.

        If, as you indicate, these are reproductions as opposed to the originals, I wouldn’t worry at all even if they’re not behind glass. The whole purpose of those types of reproductions is to look at them and enjoy them, so light them as if they were in a gallery. Not only are there other reproductions out there should yours deteriorate, the originals are still there. Plus, a quality reproduction is going to use a printing method that’s resistant to aging.

        So, enjoy them and be entirely guilt-free when you do so!



  3. Mike
    Posted October 11, 2012 at 7:43 am | Permalink

    In the commercial and institutional architecture worlds, we are specifying these more and more often. The cost is now competitive, and with the desire and need to be more energy efficient in our buildings, they are common. You see them all the time in Exit signs, street lights, accent cove lighting, and now even in typical 2′ x 4′ ceiling light fixtures.

  4. Posted October 11, 2012 at 8:29 am | Permalink

    Holonyak thought LEDs would replace incandescent bulbs, and they may still, for they’re already in flashlights.

    We are already there (sort of). The town of Arlington MA, where I live, has already replaced all the streetlights which used to be the sodium vapor type to LED lights. They last two times longer reducing maintenance costs, consume half as much energy and the light can be better oriented so as to reduce light pollution. The town has cut its streetlight energy consumption in half. Kudos to Nick Holonyak and his invention!

  5. Posted October 11, 2012 at 8:31 am | Permalink

    There’s lots of reason to be excited about LED lighting, but it’ll be a looooooooong time before the spectral quality of even the most expensive LED can compare with, for example, a SoLux filtered halogen bulb.

    I must hasten to add: there’re damned few situations where you need that quality of light — and, for most places where you’d want that kind of light in your home, you’re better off putting in a Solatube (which will have even better quality light and use no energy whatsoever). I’m not trying to put down LEDs, but rather point out that, while they fit (or soon will fit) the 80/20 rule, there’s still that 20% that ain’t goin’ away.



    • Occam
      Posted October 11, 2012 at 10:11 am | Permalink

      I’ve been living for the past three years in a house where all artificial lighting is provided by LED modules, using industrial LEDs in mounts and casings we designed and crafted ourselves.
      Considerable energy savings apart, it’s not just a game changer, it’s a life changer. The light quality is so much better.

      As I have to perform much documentary photographic work, concerns about the spectral quality of LED lighting referred to by Ben were an issue. I’m happy to report that the most recent generations of quality LED are rather satisfactory in that respect.

      For those interested in LED for photographic lighting, see the pioneering
      book by Kirk Tuck:

      We also had a “Solatube” equivalent fitted to our windowless bathroom. On a bright day during the clement season, it is amply sufficient. But in the current season and weather, it serves mainly as a proxy indicator for meteorological conditions.
      Also, a bit dim at night, though we’re working on having a wind generator powering subsidiary LED reflectors in the tube during nyctagenic photopauses.

      • Posted October 11, 2012 at 10:30 am | Permalink

        I think that’s about right.

        LED lights aren’t the ultimate in light quality, but you can get LED lights that are significantly better than what most people are used to. If you’re looking for the 80/20 solution, LED is it.

        The Solatube I have in my kitchen has a pair of standard light sockets in it, and I’ve got a pair of 96-CRI daylight compact fluorescent bulbs in there. During the daytime, you can’t even tell if they’re on or not. If you turn them on when the Sun starts to go down, you can see the tube brighten a bit, but the room doesn’t get noticeably brighter (and it’s still quite bright at this point). However, if you leave the lights on, the room never gets any darker, and the quality of the light doesn’t appreciably change.

        So, basically, I have daylight for free during the day, and I still have daylight for cheap during the night if I want it.

        Those bulbs should still have a number of years left to them. I imagine I’ll probably replace them with LEDs when they finally go — but we’ll see what the state of the market is at that point.



    • Marella
      Posted October 11, 2012 at 8:51 pm | Permalink

      Solatube, imma get me one of these, thx Ben.

      • Posted October 12, 2012 at 5:40 pm | Permalink

        You’ll love it! Superlative quality light, lots of it, and no heat transmission.

        It’s not the cheapest light fixture out there, but it’s far from the most expensive, too. But you’ll never spend a dime on bulbs or electricity, and you won’t ever have to change out a bulb. (Unless, of course, you get them to add a socket for nighttime light — but put a high-quality LED or CFL in there, and it’s almost as true a statement.)



  6. Posted October 11, 2012 at 9:39 am | Permalink

    Brilliantly clever and nice with it.

  7. Reginald Selkirk
    Posted October 11, 2012 at 9:47 am | Permalink

    LEDs are already clear winners for applications requiring monchromaticity, impact resistance, longevity or high efficiency. Once the cost comes down a bit, they will also be competitive for general white lighting.

  8. Jim Jones
    Posted October 11, 2012 at 9:57 am | Permalink


    Great for outside lighting and hallways. Also for reading lamps.

  9. dev41
    Posted October 11, 2012 at 11:06 am | Permalink

    We just finished installing eight 9-watt, 12 volt LED lamps in our remodeled kitchen. They provide superb light. Each lamp provides light approximately equivalent to a 50-watt MR-16 lamp. Our experience is that the LED technology is changing faster than lighting designers can keep up with. The available lamp wattage went from 4-watts to 5-, to 7- and then to 9-watts between January and May of 2012.

  10. MadScientist
    Posted October 11, 2012 at 12:19 pm | Permalink

    I use 8 and 12W LEDs (8W is about the brightness of a 40W incandescent) and I’m looking forward to the brighter modules. 🙂

    In some European cities you can only buy LED and fluorescent lights for domestic lighting (with the exception of low power lights for use in refrigerators, microwaves, and decorative lighting).

  11. Draken
    Posted October 11, 2012 at 1:35 pm | Permalink

    I have a couple of Philips Livingcolors, which makes me very much ledified with all the other LEDs I have around.

    Still waiting for a LED replacement for the 150W linear halogen tube in my uplight. Dimmable, please.

    And let’s not forget to mention what LEDs did for bicycle lighting. There’s no excuse any more not to carry light in the winter.

  12. Filippo
    Posted October 11, 2012 at 2:20 pm | Permalink

    Was Mr. Holonyak meaningfully (financially) rewarded by GE (a private corporate tyranny once headed by “Neutron Jack” – such a noble moniker – Welch and which in 2010 didn’t pay any federal income tax) for contributing to its bottom line?

    If I recall correctly, scientists are sometimes “awarded” patents, but, so far as I know, that’s not synonymous with significant remuneration. After all, the creative/innovative design “STEM” types all too often are handmaidens to the grasping bean-counter MBA/JD types (and investors, some of whom couldn’t solve a two-step linear equation if their lives depended on it).

  13. infiniteimprobabilit
    Posted October 12, 2012 at 3:43 am | Permalink

    As far as I’m concerned, the LED has made the pocket torch (flashlight) finally into a useful product. I never used to bother with flashlights, as you could guarantee that by the time you needed one, the cells would be half flat and the light would fade after half an hour. But a tiny cheap lightweight LED flashlight will give hours of light off three little AAA cells, it’s easy to drop into ones pocket when going for a hike in the bush, in case I miscalculate and dusk catches me several miles from the road.

    You can also (just!) drive by the light of one, believe it or not… one night at dusk I found the car headlights dimming to nothing, obviously the alternator had died some time earlier, and it was a dark frosty moonless night, on a gravel road miles from anywhere; I managed to cover five miles to the main road at an eye-straining 15 mph or so by the light of a little $2 LED torch held out the window, while what was left in the car battery ran the ignition.
    A slightly desperate endeavour but the alternative was sitting all night in freezing weather or walking maybe two miles to the nearest farmhouse, hoping it would be occupied… at the main road was a welcome street light, the occasional car, and cellphone reception. Thank you Mr Holonyak! These things really are life-savers.

    • Reginald Selkirk
      Posted October 12, 2012 at 5:53 am | Permalink

      Another winning application for LEDs: work lamps. It used to be they had to put a wire cage around the incandescent lamp to keep it from getting busted too frequently. And they got dangerously hot to the touch. LEDs are more impact resistant and efficient. Now you could even reasonably have a work lamp powered by batteries!

    Posted October 12, 2012 at 5:32 am | Permalink

    I am using 4 900 lumen 9 watt G7 LED bulbs are ordered from Amazon for $60 and 1 ecosmart 13 watt 850 lumen from home depot for $15, i prefer the whiter lights of these bulbs to edison bulbs. efficiency is a big plus

  15. Schenck
    Posted October 17, 2012 at 9:33 am | Permalink

    There’s ton’s of LED lightbulbs out there now, I have one in my house and am trying to decide between switching over my incandescents with LED or CFL, LED seems better overall.

  16. Posted November 16, 2012 at 2:56 pm | Permalink

    United By Photography also paid tribute to the achievement of the 50 year mile stone for LED lighting technology with this video

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