[HN Gopher] It was almost impossible to make the blue LED [video]
       ___________________________________________________________________
        
       It was almost impossible to make the blue LED [video]
        
       Author : keepamovin
       Score  : 252 points
       Date   : 2024-02-09 10:14 UTC (12 hours ago)
        
 (HTM) web link (www.youtube.com)
 (TXT) w3m dump (www.youtube.com)
        
       | vardump wrote:
       | 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.
        
         | creativeSlumber wrote:
         | 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.
        
         | hugryhoop wrote:
         | 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.
        
           | IncreasePosts wrote:
           | 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.
        
           | dymk wrote:
           | 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.
        
           | bawolff wrote:
           | 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.
        
             | dudeinjapan wrote:
             | It is extremely difficult to fire employees in Japan.
             | Disobeying orders is in general not a fireable offense.
        
           | willis936 wrote:
           | 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.
        
         | junon wrote:
         | 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.
        
         | legitster wrote:
         | This makes more sense having learned more about Japanese
         | business culture and the concept of salarymen.
        
         | rpnx wrote:
         | 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.
        
           | timr wrote:
           | 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.)
        
             | robocat wrote:
             | > treat undesired people like crap in order to drive them
             | to quit
             | 
             | There is a Japanese word for it:
             | 
             | Zhui iChu shiBu Wu  Oidashibeya
             | https://jlearn.net/dictionary/Zhui iChu shiBu Wu
             | 
             | A crappy NYT article but gives the idea:
             | https://archive.ph/k84cb
        
           | Exoristos wrote:
           | 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.
        
         | Schattenbaer wrote:
         | 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
        
           | ranger207 wrote:
           | I always knew there was a reason I preferred the LH351D
        
         | graphe wrote:
         | 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...
        
       | khaki54 wrote:
       | 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.
        
         | creativeSlumber wrote:
         | 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.
        
           | lijok wrote:
           | 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.
        
             | gbraad wrote:
             | Hofstede's cultural dimensions theory isa interesting read
             | about this.
        
         | nox101 wrote:
         | 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
        
       | Am4TIfIsER0ppos wrote:
       | If only it was impossible. Blue leds are abominable! [EDIT] I
       | hate white ones too so the replies aren't exactly selling them!
        
         | joks wrote:
         | ????? 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.
        
           | bombcar wrote:
           | 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.
        
             | mdip wrote:
             | 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.
        
               | themerone wrote:
               | Have you tried a sleep mask? I had to try a bunch before
               | I found one (Manta Mask) that was comfortable and stayed
               | on.
        
         | jlokier wrote:
         | 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.
        
           | jacquesm wrote:
           | White LEDs were/are also made using a UV LED and phosphor.
        
             | hugryhoop wrote:
             | That sounds dangerous, since not all emissions will be
             | converted.
        
               | jacquesm wrote:
               | Wait until you find out about fluorescent lamps...
        
               | mattashii wrote:
               | 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.
        
         | polonbike wrote:
         | Having blue allowed creating white, and anycolor (RGB) LEDs, so
         | I would not dismiss them just because you don't like the blue
         | color
        
           | mdip wrote:
           | 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).
        
         | dylan604 wrote:
         | 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.
        
           | SoftTalker wrote:
           | 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.
        
             | dylan604 wrote:
             | 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
        
           | dingaling wrote:
           | > 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.
        
             | jacobolus wrote:
             | 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.
        
             | samatman wrote:
             | 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.
        
         | graphe wrote:
         | Green SMD LEDs are just as bad.
        
         | maxglute wrote:
         | Blue leds also gave birth to purple leds, which for some reason
         | every condo building has multiple units lit up like vampire
         | dens.
        
       | ballenf wrote:
       | 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.
        
       | earthwalker99 wrote:
       | > _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._
       | 
       | The whole point of capitalism is that capital has more power than
       | labor. Any other configuration is not capitalism.
        
         | W4ldi wrote:
         | What's your point? That statement has nothing to do with the
         | problem at hand.
        
           | Draiken wrote:
           | 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.
        
           | dymk wrote:
           | 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.
        
             | ralusek wrote:
             | 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
        
               | Draiken wrote:
               | 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.
        
             | legitster wrote:
             | > 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.
        
               | dymk wrote:
               | 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.
        
         | legitster wrote:
         | 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.
        
         | dang wrote:
         | 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....
        
       | seanhunter wrote:
       | As someone who has trouble sleeping and particularly needs dark
       | sleep I wish it had been impossible to make a blue LED.
        
         | adammarples wrote:
         | no, we've put it on your headphones, your electric blanket,
         | your everything. the blue led must be seen.
        
         | BadHumans wrote:
         | Seems like an extreme stance for a easily solvable problem.
        
           | not_a_shill wrote:
           | That's how you can tell it's a joke
        
             | tekla wrote:
             | It's HN. There is a very strong possibility its not.
        
         | tekla wrote:
         | You could, you know, tape over them or something, about 5 mins
         | of work.
        
           | k_roy wrote:
           | and tape falls off, can impede functionality depending on the
           | device, etc
        
             | tekla wrote:
             | > 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.
        
               | Exoristos wrote:
               | When it's under a grill shared by a vent?
        
           | jpl56 wrote:
           | Nail polish on my bluetooth keyboard LED for the win.
        
           | p1mrx wrote:
           | 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.
        
             | pcdoodle wrote:
             | Cool!
        
         | amelius wrote:
         | The color blue is responsible for a lot of misery.
        
           | wwilim wrote:
           | Da ba dee, da ba da
        
         | zehaeva wrote:
         | 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.
        
         | hawski wrote:
         | 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.
        
       | amelius wrote:
       | 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.
        
         | kayfox wrote:
         | 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.
        
         | kken wrote:
         | https://www.lcsc.com/products/Light-Emitting-Diodes-LED_528....
        
           | amelius wrote:
           | Either out of stock or not 0805 ...
        
       | stratigos wrote:
       | 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.
        
         | comradesmith wrote:
         | Do you like OLED displays?
        
         | quenix wrote:
         | 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.
        
           | Dylan16807 wrote:
           | > 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?
        
           | jacobolus wrote:
           | 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.
        
         | graphe wrote:
         | You never had a problem with green?
        
       | BoppreH wrote:
       | 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.
        
         | tobr wrote:
         | 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!
        
           | BoppreH wrote:
           | 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.
        
           | TylerE wrote:
           | 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.
        
         | bseidensticker wrote:
         | 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
        
           | tshaddox wrote:
           | > 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.
        
       | cypherpunks01 wrote:
       | 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?
        
         | quenix wrote:
         | Yeah, all I can say is that is tracked my undergraduate
         | semiconductor theory classes pretty well. More confirmation
         | needed.
        
           | ace2358 wrote:
           | 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.
        
             | pfdietz wrote:
             | 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.
        
         | empath-nirvana wrote:
         | My 5 and 7 year old watched the whole thing with me and had
         | lots of follow up questions for me.
        
           | whycome wrote:
           | You're the dream mom/dad.
           | 
           | A cool chance to show the importance of determination!
        
         | archontes wrote:
         | 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.
        
           | cypherpunks01 wrote:
           | That's great! Much appreciated, thanks :)
        
             | archontes wrote:
             | 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.
        
         | 01HNNWZ0MV43FF wrote:
         | 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.
        
           | Smoosh wrote:
           | 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.
        
           | amarant wrote:
           | 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)?
        
             | elevatedastalt wrote:
             | 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.
        
         | JohnFen wrote:
         | 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.
        
         | thirdhaf wrote:
         | 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
        
       | Draiken wrote:
       | 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.
        
         | lucianbr wrote:
         | > 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.
        
         | dang wrote:
         | 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.
        
           | Draiken wrote:
           | 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.
        
       | tobr wrote:
       | What happened to zinc selenide then? Was there some reason it
       | didn't work out as well?
        
         | ak217 wrote:
         | 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.
        
       | angarg12 wrote:
       | 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.
        
         | Jare wrote:
         | 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.
        
           | otherme123 wrote:
           | 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.
        
             | willis936 wrote:
             | I'd rather grind to put humanity on a better path than to
             | be cozy leeching off our unsustainable path.
        
         | Uehreka wrote:
         | > 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.
        
         | foobarian wrote:
         | 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.
        
       | tmnvix wrote:
       | 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.
        
       | morkalork wrote:
       | Blue led lights on appliances and devices drive my astigmatism
       | bonkers and night.
        
       | graphe wrote:
       | Nichia still makes the best color LEDs. Semi-recently they made a
       | UV free LED for artworks.
        
       | mb_72 wrote:
       | 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.
        
         | disillusioned wrote:
         | 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.
        
         | JohnFen wrote:
         | 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.
        
       | ghaff wrote:
       | He won the 2015 Draper Prize when there was still an annual
       | lecture. Got to attend it. Amazing stuff.
        
       | Covzire wrote:
       | 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.
        
       | jfjjfjfjj wrote:
       | 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.
        
         | Gibbon1 wrote:
         | 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.
        
       | hackd997865 wrote:
       | Watched this today! The production quality and the content are
       | outstanding, 33 mins well spent :)
        
       | ddingus wrote:
       | 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.
        
       | kak3a wrote:
       | 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.
        
       | willis936 wrote:
       | 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.
        
       | crtified wrote:
       | 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
        
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