It was almost impossible to make the blue LED [video] | Hacker News Reader

It was almost impossible to make the blue LED [video]

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469 pointskeepamovin195 comments

That was a great story! We have the blue ones because one guy was willing to put it all on the line to get it done.

Amazing so much hangs on just one of us sometimes.

We also have it because the research scientist acquired real electromechanical skill. Most of the time those skills are not there and my mind is on fire thinking about what could be done, and done faster with that kind of know how more broadly distributed.

Not having that PhD sucked mostly due to peers not valuing other skills.

I know a chemistry professor who values these things. I met him while setting some polymer equipment up. (Limiting details here to keep from outing people who may well read here. (Hello, from you know who in Oregon!))

Basically, this prof has a parts and equipment depot. Anytime there is an opportunity to score inexpensive, relevant gear, they do it.

Students often build the gear they need. This may not be science grade, but it is almost always enough to validate a research path, or some other plan, including procurement or access to science grade equipment later on.

In my discussions, those students live the program and know the value they are getting.

Essentially, it is the same high value our Blue LED making friend has seen; namely, more direct agency and control with far fewer, maybe even zero dependencies navigate.

They can explore even higher risk areas of research and then upon seeing potential outcomes worth publishing, can put their stuff to work how they need, when they need.

A quick look back through history shows us a whole lot of the hard won scientific understanding we value and depend on, engineer with, came to us via people who could make things as well as think and observe. Add computation to that list as well.

Academia could use a whole lot more of this as could public research and even private research programs.

Again, great story. Love it.

Not just the blue LED.

This is what made the white LED possible.

And as can be seen, not only incandescent but also LED lighting was only made possible when it was by truly Edisonian efforts.

>Anytime there is an opportunity to score inexpensive, relevant gear, they do it.

Up into the 1980's things were done a bit differently than they are now in industrial research when it comes to equipment.

For energy, well-funded places like Exxon and Shell would store and accumulate used equipment in surplus warehouses when they recommissioned laboratories or replaced individual gear with the latest & greatest. There it would age for 5 to 10 years on average before being tagged for discard.

The material was traditionally being held as a resource as in previous decades, when it was expected that principal investigators would look first in the vast storehouse for useful items before requisitioning & purchasing new equipment for their labs. But nobody was doing that any more, energy had skyrocketed in price and oil companies had plenty of money so they had only been buying new equipment for years.

These were big warehouses, but eventually they would fill up and stay full, and they needed to make room for more on a regular basis so things were auctioned off.

Cashthedayofthesaleasiswhereisnowarrantiesofany kind.

I ended up with a very small (carefully selected) fraction of what was passing through those warehouses, and it was still a nice multiple of the tonnage that any one PhD had at their disposal during an average career. A lot of them don't want to touch the equipment anyway, they make the interns do it. So it's not often the most scientifically advanced one in the lab leveraging their hands-on experience, and conversely seldom the most capable hands-on operator having their abilities leveraged most scientifically.

I collaborated with some of their people who would visit my lab at the time, plus non-research customers and there was nothing to be ashamed of using their second-hand equipment which still had inventory stickers from the original owners. I was constantly validating equal or superior performance to their own in-house work.

They would never think of using their own surplus equipment or even going down to the warehouse to see how much overwhelming tonnage there actually was.

It just wasn't done.

Great comment. Explains so much!

>>The material was traditionally being held as a resource as in previous decades, when it was expected that principal investigators would look first in the vast storehouse for useful items before requisitioning & purchasing new equipment for their labs.

I thought this was a really well-produced video! It's difficult to communicate science to the public in an accessible way at the right level, and I think Derek does a commendable job.

I really liked the LED explanation at the 4:00 mark. Can anyone who is familiar with semiconductor physics opine on how well this explanation models the reality?

Bachelor's in engineering physics (condensed matter experimental)/EE specializing in semiconductors here. The explanation starting at 4:00 is very accurate.

When he talks about the electrons "feeling" the neighboring atoms, he's talking specifically about a result that follows from the materials being crystalline, that is, having regular ordered structure. The regular structure gives rise to a periodic potential. You plug that periodic potential into the Schrodinger equation and apply continuity conditions and translational symmetry to the wavefunction. Computing the solutions to the Schrodinger equation with those conditions reveals that there are allowed and disallowed energy levels, and also reveals the relationship between energy and momentum in the crystal lattice. You can step through this by reading the wikipedia page on the Kronig-Penney Model. This depends on the periodicity, which obviously can change depending on direction in a crystal.

His explanation, and the result that "the" band gap is a single number, isn't dishonest because when we grow semiconductor devices, we grow them such that the crystal is oriented such that current flows in the desired direction, so that simple result holds true.

Even his portrayal of the bands leaning down as potential/voltage is applied mirrors how potential change is shown in diagrams of semiconductor devices, see Streetman and Banerjee - Solid State Electronic Devices.

That's great! Much appreciated, thanks :)

Do be careful, though. Some other folks here are saying, correctly, that this glosses over the "direct" or "indirect" nature of a semiconductor. I only very slightly alluded to this when mentioning the relationship between energy and momentum.

Trying to make a long story short, it can be the case that in order to transition to another energy level, an electron also has to exchange momentum with something, usually the lattice in the form of quantized vibrations. Photons carry energy but almost no momentum, so an indirect semiconductor (one that requires both energy and momentum exchange for a transition to the conduction band) is usually an abysmal choice for optoelectronics.

I liked it, though it bugs me a little when people equate infrared and heat. Infrared is light. Light can heat things, and hot things can glow, but "infrared is heat" isn't exactly right.

I know basically nothing about physics, so sorry if this is a dumb question.

The existence of infrared LEDs seems to indicate to me that infrared light can exist without heat.

The existence of infrared thermometers seems to imply that hot stuff radiates infrared light, at least usually.

So my question is, is there any case where heat does not cause infrared radiation? What are those cases? Some special materials? Special colours(perhaps outside the visible spectrum)?

That's a good question. All bodies above the temperature of absolute zero emit electromagnetic radiation across the whole spectrum (this is called Black-body radiation). Think of it as a mixture of different amounts of light of every possible wavelength.

However, what the exact mixture is depends on the temperature of the body. As the body gets hotter, the 'peak' wavelength, i.e. the wavelength whose "amount" is highest in the mixture decreases.

Objects at room temperature emit most of their energy outside of the visible spectrum, so they are not 'visible' in the dark. However, as you heat them up, the radiation mixture moves towards lower wavelengths, closer to infra-red. Heat it up further and things become red hot, yellow, blue hot and so on.

Infra-red LEDs produce light of the the specific infrared wavelength through semi-conductors. They have nothing to do with the black-body radiation one associates with 'hot' objects.

The concept you're looking for is called Emissivity, and it describes how effectively an object can radiate (or absorb!) at a certain wavelength.

https://en.wikipedia.org/wiki/Emissivity

> Real objects never behave as full-ideal black bodies, and instead the emitted radiation at a given frequency is a fraction of what the ideal emission would be. The emissivity of a material specifies how well a real body radiates energy as compared with a black body. This emissivity depends on factors such as temperature, emission angle, and wavelength. However, it is typical in engineering to assume that a surface's spectral emissivity and absorptivity do not depend on wavelength so that the emissivity is a constant. This is known as the gray body assumption.

https://en.wikipedia.org/wiki/Black-body_radiation

In a previous life I worked for a lab designing a passive radiator that was reflective to visible light but absorptive/emissive in the atmospheric window (where the atmosphere is completely transparent). This material had the fun effect of absorbing energy via conduction/convection and then sending it out into space, maintaining a temperature slightly below ambient.

Metals don't generate much infrared light in certain wavelengths when are hot. This is why they are installed on window surfaces as thin layers to lower the windows emissivity.

I agree with you, but I think that for the general public you have to relate to what they experience, and thus intuitively know, and that is that heat “seems” to be different from light.

Yeah, all I can say is that is tracked my undergraduate semiconductor theory classes pretty well. More confirmation needed.

I would agree. Having said that I still think it was a bit wishy washy. The whole treatment of band gap energies I think is quite complicated beyond the simple diagram shown.

Also, I don't think the explanation for silicon was correct. As I understand it, the problem with Si is not that the bandgap is in the infrared, it's that it's an indirect bandgap semiconductor which suppresses emission of photons. Instead, the energy of recombination goes into heat.

Thanks yes I think I remember my whole semiconductor education to be wishy washy (according to the lecturer) even at the undergrad level. Pretty complicated stuff and I think the ‘band gap’ model is a bit of a stretch of the quantum mechanics that is occurring.

The explanation is really well done, it captures the essence of the Pauli exclusion principle without delving too deeply into the weeds. In my opinion the best part of the video is the explanation of the "hole" quasiparticle at 6:10 (I learned this as a pseudo-particle but will defer to Wikipedia [1]).

While a great introduction to semiconductor behavior this does gloss over a very important detail namely direct vs indirect semicondoctors as some others have mentioned. In the video the detail that's glossed over relates to the nature of crystals, namely that they're highly ordered repeating structures but that they don't look the same when viewed from every direction. This means that there isn't a single band-gap but multiple ones depending on the direction of the crystal you're contemplating.

At this point you may reasonably ask why the direction matters and now we unfortunately get deep into the weeds with quantum mechanics again. When a single photon is absorbed in the semiconductor system both momentum and energy must be conserved. The momentum of the photon for something like the Silicon bandgap is quite small (something like the equivalent of an electron traveling at 1500m/s) while the momentum of room-temperature conduction electrons is substantially faster [2] so as a very slight simplification transitions due to the absorption of photons are not accompanied by a change in momentum and so we only care about the band structure (and the accompanying free carriers) associated with a particular crystal direction.

In particular in Silicon you have what's called an indirect bandgap, namely the minimum energy conduction band electrons have a different momentum from the valence band holes ([3]) and as a consequence while you can _absorb_ a photon in order to make a detector you cannot make it efficiently _emit_ a photon as an LED should (something the video got wrong).

None of this matters for the heart of the video, which focuses blue LEDs in the GaN materials system which is definitely a direct bandgap material, however if someone does manage to create a manufacturable light emitter in pure Silicon expect an absolute revolution with regards to optical computing and photonics. (Not for lack of trying, this has been the holy grail for at least 20 years, possibly longer)

[1] https://en.wikipedia.org/wiki/Quasiparticle [2] https://www.chu.berkeley.edu/wp-content/uploads/2020/01/Chen... [3] https://www.iue.tuwien.ac.at/phd/wessner/node31.html

My 5 and 7 year old watched the whole thing with me and had lots of follow up questions for me.

You're the dream mom/dad.

A cool chance to show the importance of determination!

That explanation closely follows the outline of the equally good and very accessible explanation offered in the Halliday/Resnick/Walker's Fundamental's physics (11 edition, chap. 41)

I agree. Setting how LEDs work aside, I never really got how semiconductors worked, despite reading about it and talking with experts for years, until this video.

I mean, I could explain how they worked in the same ways that they were explained to me, but I couldn't connect those explanations to a true physical understanding.

But thanks to this, I finally actually understand.

Also, the LED story was fascinating.

Thanks for the billions in revenue, but remember how I told you to quit trying to use GaN to solve the blue LED problems? Well here's $147 for your patent and clean out your desk, because you're fired.

I feel like I remember he complained that Japan would likely fall behind by their best and brightest going outside Japan knowing that inside they would not be compensated.

My search-fu is failing though. I did find this interview

https://www.jsap.or.jp/jsapi/Pdf/Number02/Interview.pdf

a good leader need to be humble enough to spot when they are wrong and correct course. This guy sounds like he had control issues, and kept a grudge. very childish behavior.

There's little of that to go around in Japan. They strongly subscribe to power structures (see Senpai-Kohai) - seniors are unimpeachable and highly respected.

Hofstede's cultural dimensions theory isa interesting read about this.

Thank you, will check it out

I loved the closing interview where Nakamura explained he grew up in a fishing village with a view of the sea, inspiring his love of the color blue.

After the blue LED came onto the market in the 1990s, it took less than a decade for them to become shelf items of a couple dollars each at electronics retailers.

It was also around that time that web-based communities of computer technicians really took off. Web forums, etc.

The coincidence led (yup!) to a love-at-first-sight relationship. Funny as it may seem now, being a mere 20 years later (or: "holy crap, it's been 20 years!, how did that happen??"), there were a few years there in the 2000-2005 region during which the de-riguer of computer nerdery was to go blue LED crazy.

It felt elite, cutting edge, rare, oh-so-techy. And it's funny now, to look back at the windowed PC cases full of LEDs and garishly lit by cold cathode tubes, with our mouses and speakers and other electronic gadgets painstakingly swapped over to blue.

And within a further couple of years - from about 2005 onward, if not sooner - the commercial market had taken over the trend and made it boring, passe. We hackers and overclockers weren't interested any more. Indeed, these ultra bright things began to get annoying. Within about 5 years the modding scene's blue LED craze began, peaked, commercialised, became a liability ... at which point we began to hastily obscure our blinding modifications with another, very different, product whose very identity hinges upon the colour blue : Blu-Tack! [0]

So where did it all end up, this short-lived cultural crossover between blue LEDs and hackers? Well, basically, the commercial market morphed into the "RGB" movement of lit-up computer hardware. RGB fans, RGB cases, RGB panels on graphics cards, etc. But I still think the blue LED is pretty cool.

[0] https://en.wikipedia.org/wiki/Blu_Tack

Yes - there was Time that every consumer device insisted on using extremely bright blue LEDs for “power on” status. Even mundane things like DVRs or TVs. It became so annoying that various forms of tape were use to cover them.

I’m glad those days are over.

I still remember the blue power LED on my Toshiba laptop fading on and off in a pattern that was not quite the patented Apple "breathing" pattern, but close enough to suggest it.

Which is why I was always baffled by the decorative lights in my old office.

It was a wall with small scattered lights in different colors, so they used recessed LEDs. Fine. But instead of color LEDs with a neutral diffuser, it had red+green+blue triple LEDs to make white light, with a red/green/blue plastic in front to recolor it!

I understand how this could be cheaper to assemble or maintain, but I'll never not balk at a system that has components undoing each other's work. Feels almost disrepectful to the technology.

The blue is nicer if you do that. Technology Connections has made 3 videos over the last 5 years mostly centering around how he hates the blue led lights used in holiday lights. I think I've only seen the 2 yr old one, but now that I have I can't unsee it. The blue is just too blue. If you see a set that is all blue instead of multi-color it's unbearable. It's just too blue. White light in blue plastic is where it's at.

https://youtu.be/PBFPJ3_6ZWs?si=sTeRrqQ5umHsNCgz https://youtu.be/cQgcTkXacAc?si=CDj0G9Sh7S-wbLjN https://youtu.be/va1rzP2xIx4?si=cAp65hnmwtkrXgDc

Something odd about that ultra-blue color - when I'm outside at night, I can see any lit up sign in relatively good focus with my glasses on. Green signs, red signs, etc.

But anything blue always looks blurry unless I'm very close to it.

The lenses in your eyes refract different wavelengths at different angles - think of a rainbow coming out of a prism. Only one wavelength can be perfectly tuned to project a clear image onto your retinas. We are optimized for green, red is close enough, but blue always looks blurry.

Huh, I like that theory. Nobody else has ever mentioned experiencing the same thing as I do, though.

It's called color aberration and a big thing in telescopes using lenses.

> White light in blue plastic is where it's at.

But the commenter said it was red, green, and blue LEDs together, with a blue diffuser over them. Depending on the diffuser, that could produce a more pleasant result (by allowing some monochromatic red and green through), but it presumably wouldn't solve the underlying problem that monochromatic blue light can be unpleasant.

Are you sure they were RGB triplets and not white LEDs? Either way, is fun to imagine continuing this - grouping three of these filtered LED lights to make a new white light source, which you can then again filter with translucent plastic, etc!

Imagine, if you built a giant grid of such things, and could modulate the tranlucency 30 times a second or so, you could show some sort of.... moving picture show.

The plastic covers are slightly raised from the wall, and if you're willing to look silly you can peek behind them. They're three colors.

Amazing and inspiring story about perseverance and never giving up.

https://images.squarespace-cdn.com/content/v1/595d3fb837c581...

Though it is incredibly frustrating how ungrateful Nichia Corp was to Mr. Nakamura, the underdog who pushed through every obstacle to ultimately give them the vehicle for more than 65% of their revenue!

People like the Nichia CEO at the time, a nephew who inherited the business nepotism-style (ditching the successful methodologies of his uncle) are just goddamn fools. Any success is in spite of their unimaginative, bean counting petty mindedness fighting tooth and nail every decimeter of the way.

I think it was narcissism. Nakamura ignored direct orders to desist for years, and wound up proving that those orders were massive strategic blunders. So insubordination combined with making his superior look a fool. (On the other hand it's pretty clear we're only getting Nakamura's side of the story.)

I'm totally with you, but what's the other guys story going to be?

"This weird researcher wouldn't follow orders, and I didn't dig deeper to understand his level of commitment or anything. If I had, I would've at least seen his level of dedication and possibly rallied to support him."

That's the best possible version, and highly unlikely since, as you noted, narcissism.

Anytime I see someone intelligently committed to a cause the way Nakamura was, I respect it and will support them however I can. Even if it doesn't pan out, it's still a good story.

A counter argument is that they paid his salary for all those years, they paid for his lab, for his machines etc. They don't owe him a job.

The late founder had supported the direction of the research. It's just that the new CEO does not have the same level of risk taking vision, and instead listened to prevailing experts on the direction. He had assumed that this lone researcher is just following a dead end.

Childish behaviour aside, the conservative decision to cut costs and shut down the research is justifiable to some degree. The only problem is that the GAN research path is well trodden by others already, and therefore, a smart CEO should see that it is also a dead end.

Hi chii, thanks for adding words explaining the intuitive insight:

The more statically intelligent investment is to support exploration of the less exhaustively searched path.

It's not narcissism. I have dealt with this situation myself. It's recognizing that the boss is in over his head technically and is making the wrong decisions. This situation happens when the researcher cannot explain clearly why he knows a particular strategy is the correct one or why he knows it will work. Yes, it's confidence of a particular kind, one that you get when you understand every detail, and it requires trust.

The first ten minutes is the best explanation of conductors, insulators, and semiconductors I’ve seen. The rest is a gripping human story with science sprinkled in. The maker / experimentalist spirit strongly resonates with me. There’s a line at the end for climate change and fusion folks.

This video is to adult me what Back to the Future was to kid me: it has it all.

Kudos for mentioning Back to the Future. When I was 8/10 yo, I could recite all the lines from the first movie up to 15 min or something. I really, really loved it.

This video reminded me of an interview I did a few years back. There was an interesting robotics startup in Tokyo that I was talking to and they ended up rejecting me because I have an MS and another candidate had a PhD. The job paid $65K with very little equity and very few benefits. A few weeks later I got a job in SF that paid total comp >$250K plus tons of benefits. Japanese engineering compensation is quite poor and the stereotypes about grinding workers into a pulp are absolutely still true.

That's what I've seen, engineers working 50-60 hour weeks like it's gaming company or a faang. Except it's Hitachi. Bonus a lot of these guys are fluent in English. In the bay area they could make double for half the hours.

Quoting several others here: “We have blue LEDs because one guy bet many years of his life on his ideas, against significant opposition.”

This is great for us, but it’s important recognize the real cost of this success: probably hundreds, maybe thousands, of others also worked hard, and bet years of their lives, and… failed. In the words of Willy Wonka, they lost - they got nothing.

Statistically speaking, more of those having this natural level of talent for experimentation & discovery will not be those having a PhD.

>maybe thousands, of others also worked hard, and bet years of their lives, and… failed.

For most of them it was not the lab where they were so hard at work.

Some of them bound to be conducting their financial survival activities working in places like fast-food companies, and worse in positions where they aren't allowed to even fix things like broken milkshake machines.

Far outnumbering the highly significant percentage of PhD's who are not gifted experimentalists but they are the ones hogging their share of equipment and facilities.

So a huge amount of expensive facilities don't do any good, and the vast majority of those ultimately capable of getting something out of it end up getting nothing done. Of the sort.

I remember when blue LEDs started appearing in guitar FX pedals just out of novelty,resulting in a pedals becoming harder to use as when the pedal was on the brightness meant visibility of the controls was reduced. On pedals I made I always used fine sandpaper to increase the diffusion of each LED, and the result was significantly better. Early blue LEDs,especially, seemed to have a very narrow projection angle.

They sell LED dimming (and blackout) stickers on Amazon, and those things have been a lifesaver for me. My new USB-C charging block is brighter than the sun and the LED is functionally useless, so it's been masked with the blackout version of the stickers, but my Dyson fan which has a blue power LED (which turns to red when it's on heat mode) and BRIGHT WHITE LED temperature readout in heat mode has gotten the dimming treatment. Nice because you can still see the light, but 80% less bright, so I can sleep at night.

Dedicated stickers are probably the nicest option, but I've just used black electrical tape to completely black out a lot of blue LEDs electronics - especially in the bedroom like you. If you want to see the light, a few pinholes are enough to let some light through.

I seem to remember the early SiFive HiFive boards coming with a sticker to put on the insanely bright blue power LED on the board.

Yeah, that first generation was quite a novelty and really bright.

I got a couple blue ones but never went back for more, stuck with green and red when I built something.

The blue came in handy for a musician who was legally blind though.

This was before commercial pedals had any blue, so it did get some attention.

Blue LEDs are an amazing and badly needed advance -- but you're right, the abuse of blue LEDs has been, and continues to be, really awful.

There is something oddly humbling and inspiring about this story. The scientist thanklessly slaved away for a year and half before even producing the first breakthrough. It must require an immense amount of perseverance to do so. It also reminds me to the craft mentality and patience of Jiro dreams of sushi.

Very refreshing when contrasted with western mentality, where people can't wait to get promoted fast enough.

> Very refreshing when contrasted with western mentality, where people can't wait to get promoted fast enough.

The guy arm-wrestled the laws of physics to create something everyone including his own bosses said was impossible, and for his labors he got raised to $60k/yr (yeah I know it’s more now, but not like 10x more). I’d say this is more of a cautionary tale for ambitious inventors to demand their worth from their employers, as opposed to a fable about good things happening to people who keep their heads down and just work.

You're comparing a whole billion people to someone who went on to earn a Nobel, it's a little unfair. There's plenty of people in the West (and East, and South and North) with massive, even unhealthy grit and determination, and plenty of people in Japan that just conform to the standard work culture of the country.

Also survivor bias at 11. I bet there are currently thousands, all around the world, devoting their lives to something that would not yield any significant result. Like the nuclear fussion menctioned in the video.

I'd rather grind to put humanity on a better path than to be cozy leeching off our unsustainable path.

The puzzling thing is how he was able to just keep ignoring orders from management to stop working on the pet project. Clearly this required quite some resources to continue and he didn't get fired. I don't know if I could get away with this at a Faang-type job.

It's much harder to fire people in Japan due to their labor laws. The result is that companies often just make employees as uncomfortable as possible to try and make them quit. There are stories about Konami during its worst period for example doing things like blocking access to the internet, banning employees having their own email addresses, or forcing people to do menial jobs instead of their real jobs.

Assuming everything is reported fairly, I really can't imagine being Nichia's customer. Ever.

Sacking and not compensating the employee that single-handedly made Nichia successful by inventing a working blue LED and saving Nichia from bankruptcy is just not acceptable.

I agree with you. It says the original CEO was a researcher himself and that's why he understood the risks funded the request. Things changed after his son-in-law took control as CEO. It doesn't mention if the son-n-law had any background in the industry or semiconductor research, or was just appointed CEO just because he was the son-in-law. I think that's where the company went wrong.

Destruction of Japanese companies by "management types" sounds like a theme that gets repeated over and over. Sony/Nissan is probably the most egregious one.

I guess this is a universal; most US companies were killed off by similar thought-process.

It's complicated.

For 1 employee which disobeyed orders and saved the company you'll have 99 which disobeyed orders and don't produce anything useful or even made harm.

This is called the Halo effect.

Well, if they really thought it was a waste of time, they could have fired him in the first few years, but instead they kept funding his research. The company was doing one thing with its right hand, and something entirely different with its left.

I'm not saying the halo effect isn't real or not applicable here. But a multi-billion dollar invention warrants Extenuating Circumstances, and it's oh so very convenient that the CEO can say "well we don't want to inspire this kind of behavior in other employees!" after the profits are realized.

I think it would have been reasonable to fire him before he made the breakthrough. Sometimes you have to cut your losses. Its his treatment after success that seemed egregious.

It is extremely difficult to fire employees in Japan. Disobeying orders is in general not a fireable offense.

Yes, but the odds that someone who invents the blue LED also invents something else amazing is much better than a random employee who did not invent the blue LED inventing something amazing.

I'm not sure it is the Halo effect here. Imagine how much more money they would have made if more employees ignored the new CEO, or if there was a different CEO.

The Nichia 519A is a one of the favourite LEDs in the enthusiast flashlight world.

It's a high CRI quite bright LED, and I have to shamefully admit that I specifically specced a light in the past with this LED.

Before I knew about this, that is.

Example write-up to see what flashlight nerds talk about: https://budgetlightforum.com/t/nichia-519a/64360/43

I always knew there was a reason I preferred the LH351D

Like the other person said, nichia makes good LEDs. They make a UV free LED. https://led-ld.nichia.co.jp/en/product/lighting_optisolis.ht...

Totally. I actually went to check mouser to see if they had nichia brand stuff - a few odds and ends but they're not even listed on the manufacturer list for LEDs.

Will watch out for them and avoid whenever possible from now on.

I feel like the engineer who invented the blue LED would not want this story to cause a boycott of Nichia despite their treatment of him.

We don't know that for sure, and either way, I'm capable of making my own judgement calls.

I can, though indirectly.

Odds are good I've bought hundreds of consumer goods with Nichia LEDs in it without knowing, and I'll probably buy hundreds more.

(Not that I'm endorsing not caring, just pointing out how frustratingly hard it is to avoid giving money to companies like this.)

This makes more sense having learned more about Japanese business culture and the concept of salarymen.

They didn't sack him, he quit for better pay.

In Japan companies rarely sack employees and employees rarely quit. People are expected to stay with the same company basically their whole life. That's why he didn't get fired for disobeying orders. Firing someone in Japan is somewhat socially taboo (just like quitting) and therefore rare.

In Japan, companies are considered to be like "family". It would be kind of a joke here in the USA, but in Japan there is a lot of loyalty in both directions.

Part of the reason they sued him is probably the butthurt of him quitting. Quitting, even for better pay, is kind of like a big "fuck you" in Japan.

That's sort of true (less so these days), but it's also quite common for companies to treat undesired people like crap in order to drive them to quit. It's what they do instead of firing in the lifetime employment model -- you've been promoted to head of the floor-sweeping department. Ganbatte!

I don't know if that was going on here, but it sure sounds like it. (It could also be that the actual story is completely different than reported here, of course.)

> treat undesired people like crap in order to drive them to quit

There is a Japanese word for it:

追い出し部屋 Oidashibeya https://jlearn.net/dictionary/追い出し部屋

A crappy NYT article but gives the idea: https://archive.ph/k84cb

That's how many U.S. corps still were back in the late Eighties, early Nineties when I started working. I remember the first layoffs in my division and how shocked everyone was.

What happened to zinc selenide then? Was there some reason it didn’t work out as well?

Selenium is much more toxic than gallium, so even if it could be tweaked to work, it's a very hazardous chemical to produce or recycle. I'd expect that to be the main reason nobody bothers with zinc selenide anymore.

Blue led lights on appliances and devices drive my astigmatism bonkers and night.

I totally agree - save blue LEDs for non-domestic cases - they really suck at night - mess up the circadian rhythm.

I've always found it interesting that you could roughly date the age of electronics by the colour of the LEDs. Haven't seen (or heard, thank goodness) the once ubiquitous red alarm clock for some time.

He won the 2015 Draper Prize when there was still an annual lecture. Got to attend it. Amazing stuff.

I'm looking for __pink__ leds, but can't find a good source. Digikey has only very limited options with many packages like 0805 missing.

Pink LEDs need a custom phosphor so they may not be available in some sizes. They are also not in high demand, so not a lot of different parts are made.

https://www.lcsc.com/products/Light-Emitting-Diodes-LED_528....

Either out of stock or not 0805 ...

"This LED needs to be light red. NOT PINK! LIGHT! RED!"

Blue LEDs are the bane of my light-sensitive eyes' existence, and it pains me so to know they almost never existed at all. I keep a PC repair kit with me, even though I dont have a desktop computer, because I need to take all of my electronics apart and take these stupid blue LEDs out of them.

LED lighting wouldn't exist if not for blue LEDs. And neither would much of modern display technology. The importance of this discovery was not because we could make shiny blue light with it.

LED lighting in practice is typically terrible (though not always or inevitably): the spectrum is too blue and too spiky, without due respect for human needs. It has ruined nighttime lighting, especially outdoors in applications like street lamps, car headlamps, camp lamps, and flashlights. Whatever marketing people are making decisions in the lighting industry have insufficient understanding of human color vision and/or just don't care, consumers or other people making purchasing decisions have poor understanding of the options and their effects, and government regulation has not kept up with the technology.

Agreed on all. I'd like to add it also pains me that the power to produce about five times more light for the same electricity expenditure has been given without question or qualification to most of humankind, and yet almost no-one seems to ask themselves whether keeping spending the same energy and producing about five times as much light is what they should be doing...

Yes, the thought has occurred to me. This one seems particularly egregious, since it often results in going from a reasonable quantities of decent quality light to noxious quantities of noxious quality light.

> And neither would much of modern display technology.

The vast majority of monitors and televisions are still LCD, and they would work Just Fine if they were still using fluorescent backlights.

It would have more of an impact on phones, but not earth-shaking.

Do blue OLEDs even use the same technology?

Do you like OLED displays?

You never had a problem with green?

Lets say that the owner of the capital wants to fund hardworking individuals like "Shuji Nakamura". At the same time, most individuals seeking capital for research are just pretending to work hard, how does capital-owner identify the true warriors.

Interesting to some, YouTube force fed this video to me today after a seemingly unrelated video about Legos finished. It was a good story but I have to imagine the hacker news traffic may have had a significant effect on "the algorithm" as they call it.

Veritasium traffic is far bigger than HN.

Coincidentally I believe all birds with blue features don't get them from pigment per se but from the way their unique keratin structure only reflects blue light.

There's just something different about blue in nature too it seems.

Watched this today! The production quality and the content are outstanding, 33 mins well spent :)

People talk about inventions that change the world, but the humble LED is never mentioned!

In recent years the explosion of RGB LED lighting has altered our society and environment!

I'm aware the key to LED commoditizing is making fundamental materials for blue LED. Veritasium is a great story teller with just right amount of physical for the geek alike.

Nichia still makes the best color LEDs. Semi-recently they made a UV free LED for artworks.

I thought all LEDs are uv-free, except those specifically designed for UV?

"The results of this testing (explained below in further detail) show significant health risks from some of Cree LED’s visible light LED components when viewed without diffusers or secondary optical devices. These risks warrant an advisory notice to indicate the potential for eye injury caused by prolonged viewing of blue light from these devices."

* https://cree-led.com/media/documents/XLamp_EyeSafety.pdf

No, if you didn't watch the video I'll tl;Dr it.

Phosphors glow when they're lit with UV light. LEDs don't make a lot of UV light but it's significant enough for art studios to change to these high CRI LEDs so that the UV doesn't cause it damage over time.

If only it was impossible. Blue leds are abominable! [EDIT] I hate white ones too so the replies aren't exactly selling them!

I wasn't a big fan of the excessive blue LEDs that appeared everywhere after they were invented, either. Though it was understandable enthusiasm for something new by product developers, after decades of having only red-green combinations.

But blue LEDs are what make white LEDs work, and those have revolutionised ordinary lighting in a big way. The linked video goes into this at the end.

Blue LEDs (or white LEDs, or blue OLEDs) are also used in modern, high quality computer and phone displays.

White LEDs were/are also made using a UV LED and phosphor.

That sounds dangerous, since not all emissions will be converted.

If they (or you) use a cap that's opaque to UV but transparent to the visible spectrum, then there won't be any issues with this.

Wait until you find out about fluorescent lamps...

Blue LEDs that are on to let you know something has power is abominable, but that isn't the fault of the blue LED. What is abominable is the use of the "cooler" blueish white light being used at night indoors. That should be considered a crime against humanity.

> What is abominable is the use of the > "cooler" blueish white light being > used at night indoors.

We only associate warm orangey-white light with nocturnal lighting because of centuries of sitting around fires and candles.

And because (a) blue light causes your eyes to become bright-adapted, ruining your night vision, (b) blue light is incredibly distracting in your peripheral vision causing massively more glare than "warmer" light sources, (c) blue light screws up circadian rhythms for people and wildlife.

Don’t forget the sun. The sun gets to a warmer color at sunset, hence why warm white conveys a "go to bed" meaning.

Many millennia, actually. A million years at least, quite likely more.

Co-evolving to be comfortable with a certain quality of light, is a good argument for maintaining that quality of light, and for not using light with a quality which triggers subconscious (or conscious) discomfort.

When did blue become the indicator for "has power"? That has traditionally been red or maybe orange/amber even going back to miniature incandescent bulbs or neon bulbs.

It became that when it became available.???

exec: I'm sick of that red indicator light?

minion: They just came out with a blue LED we can try.

exec: Perfect. Use it on everything. Our products will look different, and people will like it

????? Blue LEDs made white LEDs & LED displays possible. And blue light being bad for your circadian rhythm is just as true for an LCD display as it is an LED display.

Right after the blue LED was possible, everything that wanted to appear "high value" was sticking them in as power indicators, but they were much brighter than previous LEDs.

I was at college at the time and you could read a book by the pulsating sleep blue lights from equipment.

As I read your statement sitting in my "bedroom office", I notice:

My Vizio TV which has a piece of white electrical tape[0] with aluminum foil underneath. Incredible failure of engineering that has a setting to disable the power LED, however, that setting is ignored if you use the "black screen" option that kills the screen while the TV continues playing ... a feature you are likely to only use if you like to sleep to the noise, but not the light, of the television.

My switch has a sock wrapped around the front with a piece of cardboard jammed in it to keep the blinken-lights from creating strobe effects all night.

My monitor, multi-USB charger, have similar black-tape treatments that the TV received and the power outlet next to my dresser has a piece of white tape on it -- it's a smart plug and I'm guessing there was an indicator light under that.

The thrown together solutions indicate the worst part. You tend to not discover it's a problem until you wake up at 2:00 AM and you can't get back to sleep because it's bright as early morning in the bedroom.

[0] It was all I had at the time.

Have you tried a sleep mask? I had to try a bunch before I found one (Manta Mask) that was comfortable and stayed on.

Having blue allowed creating white, and anycolor (RGB) LEDs, so I would not dismiss them just because you don't like the blue color

Of course -- and all of that has lead to the display technologies we take for granted these days and a number of other advances (low cost, low energy, high output LED lighting, for example).

This is an example of the reaction to any new technology -- electric cars catch fire and we suddenly forget we drive around in vehicles carrying large quantities of explosive gas (and work via controlled explosions). They get stuck in the winter and we forget the few times a winter we had to jump our gas car to get somewhere. I remember actual indicator lamps ... granted, they tended to serve very temporary lighting purposes and despite that were still often burned out (if your elevator in the 80s had floor indicator lamps, 25% or more were dead).

When it's good new technology, as the blue LED objectively is, it becomes mass produced and then mass adopted as "the cool new thing." And it was the cool new thing -- I remember thinking how neat the deep blue LED on my first AV receiver was. And then it becomes over-adopted. Most of the LEDs I have covered up in my bedroom aren't blue -- they're cool white[0] and oh so much brighter than the various-shades-of-blue ones that adorn other equipment throughout my electronics stuffed house.

[0] If they were warm white, but dim, I'd probably have a similar "that's neat" if they looked like earlier indicator lamps (but cleaner).

Blue leds also gave birth to purple leds, which for some reason every condo building has multiple units lit up like vampire dens.

Green SMD LEDs are just as bad.

It's incredible to see with cases like this how extremely absurd the relationship of capital and labor is.

If I was someone aspiring to be a researcher, I'd most definitely give up due to stories like this. The person created probably close to trillions of value to humanity (his LEDs spawned multiple new industries), yet he was compensated less than what I make with web development.

Meanwhile the CEO and other businesses profited from his research for one reason only: they already had capital.

Call me crazy but smart people that want to do research should do it and get well compensated for it, even if they don't invent something as pivotal as this. But because of stories like this, many smart people will never even consider a career as a researcher because the majority would be rewarded with poverty.

Meanwhile if you release a new shitcoin at the right time, or you're posting near naked pictures on Instagram, you get rewarded handsomely.

What a fucked up society we created for ourselves.

Could you please stop using HN for ideological battle? Your account has been doing this a lot lately, and when an account is primarily doing that, this is a line at which we ban the account. Past explanations: https://hn.algolia.com/?sort=byDate&dateRange=all&type=comme...

We detached this subthread from https://news.ycombinator.com/item?id=39314755.

I don't understand. This is literally part of what the video talks about: how he got fired after giving them billions. How is this an ideological battle? It's what was described in the video.

I don't disagree that I talk about capitalism on some threads that aren't specifically mentioning it, but in this case it's 100% part of the content.

I can only hope that the same treatment happens for accounts with the opposite view.

I believe you that there was a point of contact with the article but the problem is that your comment went on a generic ideological tangent from it, straight into regular flamewar territory, which is what we're trying to avoid.

The more important point, though, is the pattern of posting like this. An isolated case isn't a problem but if it becomes a pattern, that's different; that's not the intended use of this site.

For sure accounts with the opposite view get the same treatment—as long as we see them. (We don't read everything that gets posted—there's far too much of it.)

People see what they wanna see, especially if their hobby is to promote empirically-failed worldviews.

EG Moonshot research grant of $3 million / 15% of company's revenue is somehow capital exploiting labor, or whatever such superficial Das Kapital take, and no cognitive dissonance that inventions of this sort somehow didn't materialize in DDR or SSSR.

Without that corporation behind him there's no way he would have been able to go to America for a year, buy a brand new deposition machine and then spend more years working on it.

> The person created probably close to trillions of value to humanity (his LEDs spawned multiple new industries), yet he was compensated less than what I make with web development.

While decrying unfairness towards a single researcher, you seem to ignore the contribution of who knows how many people comprising "multiple new industries". I mean, the people working in those industries also contributed to those trillions, no?

It definitely seems unfair to Nakamura. Just pointing out it's really hard to be fair to everyone, as your comment inadvertently proves. At least he got a Nobel prize, which means both recognition and money.

It’s always been like this.

Professions that leverage passion pay peanuts.

Wow, I had the completely opposite interpretation. The only reason this thing got created was because one rich person bet $3 million dollars on this researcher. There would have been zero chance of this research ever getting funded outside of capitalism.

As someone who has trouble sleeping and particularly needs dark sleep I wish it had been impossible to make a blue LED.

Seems like an extreme stance for a easily solvable problem.

That's how you can tell it's a joke

It's HN. There is a very strong possibility its not.

I wonder if there is a part that could replace signaling LEDs without emitting their own light. I think transflective LCD could work like that. Make it small, round and with two contacts like a diode.

no, we've put it on your headphones, your electric blanket, your everything. the blue led must be seen.

The color blue is responsible for a lot of misery.

Da ba dee, da ba da

Maybe try an eyemask? I will admit the feeling takes a little bit getting used to but I get way better sleep with it than without.

You could, you know, tape over them or something, about 5 mins of work.

I put a few layers of kapton tape on my monitor LED, so the bright blue is now a dull green, and the orange standby color looks the same.

Cool!

Nail polish on my bluetooth keyboard LED for the win.

and tape falls off, can impede functionality depending on the device, etc

> tape falls off

So re-apply it when it falls off after 5 years

> can impede functionality

Give me an example where covering up a blue LED impedes functionality.

An example?

https://www.belkin.com/magnetic-portable-wireless-charger-pa...

The offending LED is the black spot in this picture:

https://www.belkin.com/dw/image/v2/BGBH_PRD/on/demandware.st...

Look no further than that. Note, I have the black one from Amazon, and it's no longer for sale, so maybe they realized the mess-up.

It's been my charger for iPhone current-gen since July of this last year and it's horrible.

The LED on this thing is not EXACTLY blue, but it's birthed of the exact same hellhole, and close enough in general color to count.

So let's walk through this:

1. It's piercingly bright in the exact perfect shade of light that you can't help but notice everywhere in a dark room.

2. It's designed in a way that projects that thing across the room like a spotlight.

3. The light comes out of a silly small surface on an inconvenient placed spot on the edge of the shell. Meaning electrical tape lasts about 5 minutes.

3. I'm not a stranger to cracking things opens, but with this thing is hermetically sealed, I haven't been brave enougth to do it yet.

I tried to just shove a needle in there to short out the LED, but it's probably some kind of surface mount and I couldn't hit it.

Alternatives to cracking it open have been stuffing like 4 inches of electrical tape in the hole with a dental pick/needle, and then covering it up with more tape to seal it in. This took a while, but it also lasted at least two months. But again, not permanent.

The point is, anything that could potentially be primarily be used in a bedroom, shouldn't be a cool light.

When it's under a grill shared by a vent?

[flagged]

Please don't take HN threads on generic ideological tangents. They're tedious and repetitive, and therefore boring. Plus then they turn nasty.

https://hn.algolia.com/?dateRange=all&page=0&prefix=true&sor...

https://news.ycombinator.com/newsguidelines.html

Edit: can you please not use HN primarily for ideological battle? We have to ban accounts that do that because it destroys what this site is supposed to be for. past explanations: https://hn.algolia.com/?sort=byDate&dateRange=all&type=comme....

Blaming literally anything wrong on "capitalism" is peak intellectual laziness. Especially to use a canned definition that no one would agree to except those that would confirm your priors.

Do these problems not exist under feudalism? Mercantilism? Communism? Did soviet inventors fair any better?

You're better off calling a spade a spade. Weird reductionist absolutes about society don't make any of us any smarter and only steer discussions into unhelpful directions.

What's your point? That statement has nothing to do with the problem at hand.

The problem is that he was unfairly compensated by the economic system (capitalism) he works in, and had to fight for years only to just about break even on legal fees.

The guy's gumption led to the invention of a multi-billion dollar pear year industry, and he got basically none of it.

The inverse also happens, though, because socialism fails to capture the value. According to the labor theory of value, for example, his work would’ve been valued at some function of (training * hours worked). Despite creating billions in value for humanity, he would’ve been treated very similarly to the rest of his coworkers

Nobody's talking about socialism.

But let's say it was a more socialist society. As a result, everyone would be earning more, including him. And maybe the CEO that tried to fuck his research would earn less.

IDK but for me that sounds like a very good trade-off, given the CEO did nothing, as always, and got billions.

> The guy's gumption led to the invention of a multi-billion dollar pear year industry, and he got basically none of it.

But... the billion dollar industry is also capitalism? This logic is circular and makes no sense. If there is no capitalism there is no compensation to be distributed in this case, period.

The argument that he was unfairly compensated based on merit is fundamentally a capitalist argument. You can't play it both ways.

Are you saying the outcome here is fair and desirable?

The first step to fixing a problem is admitting one exists. This seems clearly like a failure of capitalism to reward the innovation of a person who actually did the innovation.

How is that not the problem at hand?

The only reason the inventor didn't get properly compensated is because the system is designed to reward existing capital.

I can guarantee you the CEO that inherited the position due to family ties didn't earn $60k a year. Neither he worked for a year and a half without weekends.

This is capitalism.

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