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

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

#121

Post by jacobolus »

dingaling wrote: post #111
dylan604 wrote: post #12

Earlier quoted context omitted.

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.

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

#123

Post by Uehreka »

angarg12 wrote: post #102

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.

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

#125

Post by samatman »

dingaling wrote: post #111
dylan604 wrote: post #12

Earlier quoted context omitted.

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.

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.

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

#126

Post by archontes »

cypherpunks01 wrote: post #119
archontes wrote: post #117

Earlier quoted context omitted.

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…

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.

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

#127

Post by whycome »

empath-nirvana wrote: post #87
cypherpunks01 wrote: post #48

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?

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!

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

#128

Post by jfjjfjfjj »

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.

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

#129

Post by whycome »

dang wrote: post #94
wutwutwat wrote: post #21

Earlier quoted context omitted.

[flagged]

" Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize. Assume good faith. " https://news.ycombinator.com/newsguidelines.html

Does whatever they said necessitate 'flagging' rather than just downvoting? Groking it from the further discussion, it seems worthy of at least talking about.

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

#130

Post by nox101 »

khaki54 wrote: post #4

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

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