The blue LEDs that existed before the current InGaN blue LEDs

Although a gallium nitride based blue LED was demonstrated in the early 70's, The silicon carbide based blue LED was the first commercially available. This video takes a quick look at them.
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[@JohnAudioTech]

Before anyone calls me out; yes, I know the internet existed in the early 90's. It was very limited in accessibility.

[@matambale]

Those DigiKey catalogs were HUGE.

[@DrewskisBrews]

​@@matambaleand there was a pretty steep minimum order threshold (was it $100?) that kept young enthusiasts, such as myself at the time, from even considering them as a parts source. To this day, I have a subconscious avoidance of Digikey, under the mistaken premise that they are a "commercial only" supplier.

[@matambale]

@@DrewskisBrewsI remember they had a minimum order back in the day, but I can't remember what it was. No minimum order now, though.

[@russellhltn1396]

@@DrewskisBrews I don't think it was that high, maybe $10. But as I recall you might want to hit $100 as the shipping cost depended on the purchase. Given a choice between buying more parts than you need or paying for shipping, you might want to stock your drawers.

[@antibrevity]

I think your point was that people still ordered Mouser and Digikey stuff from thick paper catalogs. Same with B&K Photo. These were all built as mail-order companies, not Internet stores. They had minimum orders partly due to the high costs associated with the huge catalogs. While today's searchable catalogs are efficient, you don't get the same enjoyment from turning page to page and seeing neat components and tools you didn't know that you needed.

[@AndyGadget]

I worked in an electronics shop as a holiday job in '78 or so and we stocked blue LEDs. These cost £40 ($50) each and were just about visible in not-too-bright room lighting. We didn't sell many.

[@Cornz38]

In the 90's, i worked at Maplin Electronics in the UK and we started to sell a water clear blue led. They were £17.50 each!! A red, yellow or green led was 11 pence.

[@johnyang799]

The sky blue color is really beautiful.

[@LarixusSnydes]

It sure is and one of the advantages of this LED is that the compounds needed to make it are abundant in nature. You shouldn't breathe in SiC powder, but otherwise it's a relatively harmless chemical.

[@vaclavtrpisovsky]

I wish the two LEDs shown together were adjusted to comparable brightness for a color comparison. I’m glad that we got efficient deep blue because it allows for wide-gamut RGB displays, but I would still prefer dimmer, softer blue indicators on my Bluetooth earbuds, monitor, powerbank, NiMH charger etc.

[@Mr.Leeroy]

cyan > blue for sure. Blue as an indicator is a spawn of satan.

[@bobcat6653]

I was designing a climate control for the General Motors 1991 Buick Regal, their stylist INSISTED on blue indicators for the temperature control, I started of with the SiC 'baby blue', GM was NOT happy because they were so dim and pale, but it was that or green. And about the time for start of production, the InGaN blues came out of nowhere, expensive yes, but I, along with many other Engineers, adopted them with little hesitation. I think I still have a few of the baby blue SiC LED's. Very cool to see you post this video.

[@rblubb]

In the late 80s and early 90s, Volkswagen models featured LEDs of various colors in the speedometer. In Germany, the indicator light for high beam needs to be blue. Therefore, they decided to place a blue cap over a standard bulb alongside the LEDs. Problem solved :D

[@emmettturner9452]

@@rblubbwell, that’s the way all the colors were done before LED. Heck, my 2000 Pontiac Montana has little red sleeves over white incandescent bulbs all over… from behind the gauge cluster where at least two are blown to underneath the steering wheel CD playback controls where you can feel the heat while driving and the door lock/window controls. The Oldmobile version of the same van (Silhouette) has blue lights in all the same places. It seems kind of silly for a vehicle produced in 1999 but they just weren’t using LEDs. This is because GM tried to use all the same parts across all their cars and these bulbs were already certified for automotive use across the board. Heck, my 2011 Toyota Corolla still used incandescent bulbs everywhere.

[@piotr433]

@@emmettturner9452 Silly but true. The only place my 1999 Ford Focus (European version) had LEDs was the third stop at the top of the rear door. The rest were incandescent bulbs. And yes, I could feel their heat in some places.

[@DavidHembrow]

I bought one of the first Pioneer dvd players in 1998 (it cost about $800 as I recall). It had a fairly bright blue light which shone when there was a dvd in the drawer (it was not lit for a cd or vcd). Wow, blue led, I thought, but when i took the top of to take a look it turned out to be a tiny incandescent bulb behind a blue piece of plastic... That was still cheaper than a blue led at that time.

[@1974UTuber]

Don't watch Veritasium. He is often wrong. I prefer your content over his any day of the week

[@1pcfred]

It was an interesting video. He interviewed the guy that invented it. He's a strange bird. The guy needs to switch the the decaff.

[@kapteinsuperskoot6986]

Volkswagen was one of the first car companies (to my limited knowledge) that used blue LEDs in dashboards for high beam indicators. My 1980 Transporter has the ugly mustard yellow one, and my mother's 1988 Fox (upgraded Jetta Mk1) had the blue. My later 1996 Citi Golf (upgraded Mk1) also has the blue. It isn't sky blue, rather a deeper between-french-and-royal blue maybe. It was a blue lens as well, not clear, and diffuse. I remember my Dad saying they were expensive. When I studied electronics in the mid-90s, they were becoming affordable enough for university project use. Fun trivia . Thanks for the informative video.

[@generalleigh7387]

The feeling we get from connecting wires- it’s the end of an era. God bless you buddy I love your channel.

[@jhonbus]

Wow dude, these are totally SiC!

[@dorfschmidt4833]

😅👍

[@chrisg6597]

I also watched that KZbin video regarding the development of Blue LEDs. The very first blue LED I saw was one that a school/college friend of mine bought around 1978/9 from RS components in the UK. It couldn't have been any later than that as he dropped out of collage to work for his dad's company in 1979. As said in this video, the LED was very dim and very expensive i.e. multiples of pounds compared to the 7-8 pence for a normal Gallium Arsenide red LED.

[@wtmayhew]

I got some silicon carbide blue LEDs at the Dayton Hamvention, has to be at least 30 years ago. Blue was quite a rarity at the time and mostly used in specialized medical equipment where blue was advantageous for measuring certain chemical properties. The light output is only a few Lumens and by today’s standards they look like factory seconds because they are dim. The pale blue color is quite attractive and they make nice power indicators because they are not excessively bright.

[@errorerror1337]

Great video and love the followup to Veritasium. I had no idea there was an LED nerd lurking within me until I watched his vid and seeing yours has helped quench my thirst for more LED content. Thank you!

[@willyrivero470]

I'm also an electronic nuts and as you, I love anything that produces light, specially leds. I have boxes with them. My wife has an issue with me because every year some Christmas lights "magically" dissapear when she tries to re use them. Thanks for your videos!!

[@mrb.5610]

'Star Trek - The Next generation' from the 90's has a noticeable lack of blue lights on its hand held scanners !

[@supercurioTube]

That was missing from the story told in Veritasium's video! Thanks for showing us 😀

[@johnyang799]

I didn't think it was missing but glossed over or merely told as fake blue. Frankly it is dim, pale and not exactly blue. But the sky blue color itself is quite beautiful.

[@eicydee3212]

@@johnyang799Also, I found the fact that SiC was used for LEDs quite interesting. Because that means that SiC was used for LEDs, then was a bit out of favor for 10-20 years, and is recently used for high voltage semiconductors (SiC MOSFETs and diodes) again.

[@dorfschmidt4833]

Presumably we are talking about the Telefunken TLHB5400 silicon carbide LED.

[@eicydee3212]

Thanks for giving a part number. Here would be a datasheet from 1995 of the original SiC version (looks like the TLHB5400 was at some point "upgraded" to GaN and still sold as TLHB5400): pe2bz.philpem.me.uk/pdf%20on%20typenumber/T/TLHB5400.pdf 2 milli-lumens brightness. Wow, LED technology has improved since then.

[@Arcygenical]

I sure wish we had these as the default on nearly all technology produced over the last 20 years. The ones that make sleeping within a mile radius nigh impossible.

[@mysock351C]

More of a problem of cheap Chinese products that absolutely just run the piss out of them to make sure you "notice" the product in the store. I have a PC that I built when the white/RGB LEDs with a clear sided case deal became a thing and and it looked like a hydrogen bomb going off the first time I started it up. Now its completely dark with just little white and blue dots where the LEDs are due to degradation. However, if you size the resistor properly so they light gently like their older counterparts the modern blue ones are actually quite nice. And as a bonus they last forever at the lower current.

[@PunakiviAddikti]

Skill issue, I love blue LEDs mmm yeah beam it directly into my retinas that's how you get a good night's sleep

[@andreasu.3546]

So true. The front side of my Philips Hue bridge needed three layers of duct tape before it became tolerable at night.

[@joeofloath]

I use a black paint marker to black them out. They still shine through but you have to be looking at it to see it. Highly recommended!

[@tookitogo]

The problem is that for ages, 20mA was the standard current to run indicator LEDs at. With early LEDs, this made them barely visible indoors. With modern LEDs, 20mA is retina-searingly bright. But many designers forget this, and continue to use 20mA. I typically run modern indicator LEDs at 0.5-1mA.

[@CMDR_Hal_Melamby]

One issue was that there was competition regarding the older tech. I worked in a university lab where we had a methodology to improve those LED intensities by factors over 1000 fold. My research supervisor held the patent on the manufacturing process for polythiazyl (SN)x a sulphur-nitrogen polymer chain that we made in the lab by electrolysis. Unfortunately, the Japanese LED companies had patented the applications of the material so it became an impasse. As a result Arthur's patent lapsed. A similar material was adopted in some screen technologies in the 2000s, I believe. I decided not to work on (SN)x synthesis and applications for my PhD and focused on organic magnets instead. We did make a breakthrough in that field with the highest Curie temperature for a magnetic material containing no metal that was rejected by Nature as the results were too good, although it was confirmed by other groups and the 1996 paper is still being cited today although other materials beat it about 10 years ago.

[@ShellacScrubber]

I remember paying £20 for ONE of the earlier dim blue LEDs !

[@jerryking2418]

Saw the video. Very interesting. The fact that we have harnessed the ‘quantum leap’ to produce light indicators is very remarkable. Thanks for reminding us.

[@Tore_Lund]

I remember those LEDs when they first appeared in my electronics store. $15 in 1989 prices. My store sold them individually, mounted in a jewelry box, because of the insane price.

[@qintusquark4854]

Just curious, what's the forward voltage of those SiC LEDs? I tried googling but haven't found anything about it.

[@TheRealEtaoinShrdlu]

Are you saying "all [sic] struck"?! The actual saying is "awestruck". As in struck with awe.

[@CraftAero]

In the early 80's I saw a car stereo indicator light (led) that lit either red, green or yellow depending on input mode. Seemed like sorcery at the time. +/- for green, -/+ for red and AC for yellow.

[@Spentelectrons]

Hmm. Bright enough to be commercially viable... I find all modern led too bright. Light up even one on a breadboard, and then stare into it tweaking the circuit... that's terrible. Ben Eater must be wearing welding goggles

[@jakubczajka4275]

Purchased first blue LED around 1999-2000 for my tube amp. It was like $1.25 (expensive compared to other colours) and soo cool looking. Now I am back to red LEDs and blue is my least favourite. I also remember reading about blue lasers in 1990s. They were overheating quite easily I think.

[@kaasmeester5903]

I bought one when they hit the market. I think around €15 in today’s money for a single one, but I just had to have one.

[@1pcfred]

John always on the cutting edge of technology. $10 for four barely visible LEDs. Awesome! Recently here I had to cull all of my vintage LEDs from my parts organizer drawers. I still have them but I can't really mix them with modern LEDs. If you would have told me in the 70s that someday we'd be using LEDs for lighting I'd have laughed.

[@frogz]

i bought my first blue led at radioshack, came as a pair for like $4, it was definitly brighter than this but i remember these powder blue leds!!

[@johnrehwinkel7241]

I also picked up some of the early silicon carbide LEDs, just to have some blue LEDs. I had the same thought when I saw the Veratasium video. A friend of mine got one of the blue LEDs and put in in a box with a switch and battery, he called it a "geek detector". He'd turn it on, and if someone came over to ask "is that a blue LED?" he knew he'd found another kindred spirit.

[@steveswan5714]

I have had an obsession with LED's since the beginning of them and still to this day 😱😂👍

[@dorfschmidt4833]

I also found LEDs fascinating as a child.

[@volvo09]

​@@dorfschmidt4833 same, something making light without heating a wire.... I remember going to the parts store with my dad as a kid and they had a couple dim blue LED's on their display and I was amazed, because LED's had always been red, orangey yellow, or green, I thought blue was impossible. I wanted to buy one but it was stupidly expensive (I remember my dad saying no) and I would have blown it up anyways by not limiting the current.

[@steveswan5714]

@@dorfschmidt4833 I think I'm still a child 🤣

[@jeffmassey4860]

I bought the 100 packs of LEDs from Radio Shack in 1978. In 79 or so I thought it would be cool to have car and truck marker lights made from these... Needless to say,I did not cash in on that idea. LOL

[@steveswan5714]

@@jeffmassey4860 I have bought various types for different situations and have so many I could supply Rapid 🤣

[@mickeythompson9537]

I love those early SiC leds - such a unique light. Bought a bag of them in the mid 90s when they were about $3 each. Thank you for the video reminiscence.

[@tenmillionvolts]

I was excited when I first saw yellow LEDs. So pretty. I started replacing every power indicator I could find, just so people would be amazed that it wasn't red or green. Then I saw a white one and I couldn't believe it. LED light bulbs!!!

[@gorak9000]

Yellow and orange were around at the same time as red and green - maybe slightly later than red, but not unheard of. They just weren't as bright as the "high efficiency red" ones that came out later, but based on the same GaP chemistry as red and "yellow-green". I always liked the clear lens orange ones - it was actually a really unique color. We had tons of them available in high school electronics class, but you never really saw orange in any products.

[@pencilography2025]

Couldn't they just mix red and green? Or does that make it less bright and efficient ?

[@jensschroder8214]

I had a VW Polo. The speedometer had indicators with 5mm LEDs. A blue indicator is usually required for the high beam. But a yellow LED was installed there and the vehicle had permission for it recorded in the papers. Other vehicles used a blue bulb instead. Around 1990 I bought one blue SiC LED for 20 DM, which I then installed as an indicator for the high beam. I had to align the LED so that it shone into the field of vision, the blue LED was not so bright. That was my car tuning 😉

[@g0hjq]

I'm in the UK and had a VW Polo in the 1990s, but I'm pretty certain mine did have a blue SiC LED for headlight main beam. It was the first I'd ever seen. The poor efficiency was an advantage in this application, as you don't want it to be too dazzling

[@andybaldman]

We used to be awestruck by a blue LED. Now we are literally surrounded by them, and don’t even notice them. That’s worth thinking about.

[@circuitsmith]

As I remember when those blue LEDs first appeared in the DigiKey catalog they were $50-60 each!

[@retireeelectronics2649]

Excellent, sadly when I checked my old stock, none were that old. Probably since I was a cheap bugger.

[@iceberg789]

i cant imagine led lighting in homes and outdoors was sci fi stuff just 15 years ago ...... 😳

[@Derpy1969]

Are you saying “all-struck” or awe-struck as in Struck with Awe?

[@1RandomToaster]

Amazing how Blue LEDs went from impractically dim to the brightest thing in the universe.

[@timowagner1329]

I love LEDs!

[@gkdresden]

In fact almost every diode is an LED. The 2N4148 emits in the near infrared. You can see it glowing with your mobile phone camera. The silicon pn itself is a very stange light emitter. The charge carriers can only relax from their meta stable state when the take a phonon from the crystal lattice with them. It means, the pn structure gets colder if it emits light. But the loss processes generate by far more heat than the anti-Stokes cooling generates cold.

[@АлексейРябов-р4д]

As i know first commercial blue leds were out of indium antimonide (InSb). They were very inefficient and expensive.

[@SuburbanDon]

First time ive seen these. I started with digiikey in 1979. Filled our the order form and mailed it to them with my check.

[@jordanwaeles]

I had one of these back then!! I was also struck in awe and also paid around $3 for one LED. I didn't know it was a different technology, I did notice however when the new blue / green and white LEDs came in that they were SO bright and a more pure blue. The early white LEDs lost brightness quite fast, I had a very early lightbulb made out of individual 5mm cold white LEDs as a night light. After a few months, you couldn't even see it was on anymore. I'm going to be searching for SiC blue led's, i want to own these puppies again.

[@1pcfred]

There is a downside to being an early tech adopter. You need to give tech time to mature to a useful state. When products are first available they're usually junk.

[@volvo09]

I had a set of Christmas lights that I swapped in some cheap eBay bottom of the barrel warm white 10mm LED's... Had them around my workbench and they got very very dim within a year of almost daily 4+ hour use. I didn't notice it for a while until I swapped one out, it was at least 50% loss of light output. None died, but they just got soooo dim. Probably why 100 cost $5 shipped... Haha Edit, I'd also love to find some of these. I wanted to make a new LED house number sign out of vintage LED's.

[@keithblume5159]

I watched the special on Blue LED last night. I bought my first batch of Blue LEDs in 1998 and they were soo expensive.

[@jimmygervaisnet]

That's a very nice sky blue! I had no idea those were around. The Veritasium video was amazing.

[@Felix_Fausto554]

Green LEDs are very beautiful too, the first ones had an emerald like color.

[@volvo09]

I like the early green ones with a clear top that look like they have a glowing "cube" of green inside them. I recall seeing these in the late 80's as a kid and staring inside them. The modern ones don't look like that.

[@jul1440]

"Things that produce light" are called _lamps._

[@therealchayd]

I had a couple of these SiC LEDS back in the '80s and they had the nicest color ever, but they cost £9 (the equivalent of £33.05, or $41.78 in today's money) EACH. I'd love to get another one just for novelty value🙂

[@jagmarc]

A colleague in the 80s/90s probably made one of very first industrial applications using a blue LED for narrowband fixed wavelength absorption spectrometry.

[@luizmarxsenjr]

I remember when I bought my very firsts blue LEDs in 1997, I spent U$D5.00 for each one, were a 5mm diffused LEDs that weak glows, the seller told that they are from some South Korean maker, sure these are based on the silicon carbide technology... Greetings from Brazil!!!

[@MCPicoli]

I have a Philips 9W LED bulb from mid 2009. It was very expensive for the time. It is still installed and used several hours per day. Almost the same brightness as new.

[@MrXenon1977]

Just due to its oddity: Here in Germany a company sold little incadescent bulbs molded into a blue housing with the same geometry as a standard 5mm-LED. This must have been in the end of the 80ghties or beginning of the 90ghties. They have been quite bright and cheap compared with the authentic SiC-LEDs. The major disadvantage was their limited lifetime. Rumors say that the High-Beam-indicator of VW-dashboards of this time have used this "fake"-LED. Everytime I have seen the blue light from the LED-shaped surface of these cars I was heavily wondering where VW finds blue LEDs. But maybe they even had an early source of "good" SiC-devices.

[@emmettturner9452]

I have a couple of these that I believe came in assortments. Velleman sold assortments with various sizes and colors just tossed loose into a paper-backed plastic package.

[@tvelektron]

In the late 80s i got my hands on some "fake" blue LEDs. Just tiny bulbs inside a 5mm LED housing. Worked reasonably well in terms of color and brightness but comparatively quite a lot of power, i think it was 50mA at 5V...

[@TheNiteinjail]

I have alwaya been a fan of LEDs .. "TechnoSprinkles" 😂 i can remember very quickly after encountering the Nichia blue LEDs ... "These things are going to change like everyday lighting. Stage lights, automotive lightning.. street lights. I very quickly could foresee a whole range of things we now have.

[@AnnaVannieuwenhuyse]

$3.5 in 1990 would be approximately between $8 and $8.5 today. That's an expensive LED.

[@matthiasmartin1975]

I have one of those SiC LEDs in my stash too. A product manager for the Swiss distributor of Stanley LEDs gave it to me, they were 5 Swiss francs a pop.

[@GreenAppelPie]

I used these on small professional products, but I purchased them from Tech America for $7. I was stunned by the brightness of first white CREE LED I saw running, I knew at that second the LED light was soon to be a thing.

[@soumikdas5857]

Hey john i designed an amplifier....and its running quite good...but due to lack of instruments i really cant check its stability and response....it will be really helpful if you test it

[@hellhound-si5oz]

I don't know how far west norvac Electronics went but I know where I lived we had one and they had blue LEDs and they were hella expensive

[@pedrova8058]

and as a way to compensate, now everything is full of ULTRA bright blue LEDs... I hate those lol

[@pault6533]

Eyes are less sensitive to blue light, increasing the challenge of producing an adequately bright blue LED. It would have been interesting to learn about the development of the UV LED too, I suppose it was easier to develop once the modern blue LED was released?

[@burgersnchips]

Such a nice colour, shame they didn't continue the development. Modern blues have such a harsh colour and generally too bright (IMO) for use as indicators too.

[@paulmcgrath2175]

Bought some from digikey back then, still have one in use today. I might still have 1 or 2 floating around as well. Was made by Cree as I recall.

[@watchmakerful]

I had a similar LED in late 90s. A strange "feature" of that LED was its forward voltage drop of around 4 V at 10 mA.

[@boardernut]

I thought exactly the same while watching that Veritasium video, he mentioned it very briefly at the end, but god that guy put videos together talks like he has a doctorate on everything.

[@xenoxaos1]

And here I am looking at my Monsanto red and green LEDs and quite a few of the MAN 10A 7 segment displays

[@ohmbug10]

I can remember the exact spot I was standing in the mill I worked at when a salesman informed me that true blue LEDs were finally going to be available. I was stunned. I told him white ones will soon follow.

[@kakurerud7516]

I made so much money modding the playstation power led with the earlier blue ones. they were just enough to look cool. each led was just under 5$ at radio shack and I did the mod for 20$

[@peterjameson321]

I have one of these early silicon carbide LEDs. I suspect that most of them were purchased by curious enthusiasts.

[@mkepler5861]

yeah, I saw that video too, very interesting. I had not idea it was that difficult to make the blue LED. and then he pretty much got screwed out of what he did.

[@lezbriddon]

I had a few, never knew they would be a part of history/collectable

[@HighTreason610]

LED technology certainly is fascinating and this was a nice little demonstration. I can't recall if these were the type that went pinkish as they aged and dimmed. Both the older blue and red were definitely more pleasant to look at, especially a particular red from around the start of the 90s that had a rosy tint (which I'd like to find a supply of) and a blue I have from the 70s... that's a strange one. The LED is encapsulated in a metal tube and runs hot. It produces what I can only describe as a dim but beautiful 'turquoise sea blue' (around 495-505nm) and the device it is in only ever lights it momentarily. I once read a paper from the time that spoke of overdriving green/amber. My suspicion has always been that something is going on in the tube, maybe polarization like you see on VFDs where they turn the green/blue to a yellow, but in this case they'd somehow be doing the opposite. I was convinced for years that it was a grain bulb, but no. Of course I've never dared cut it open to figure out what's actually going on and I've never found another one, even in other examples of that same device. Strange how as technology 'improved' the blues got bluer, but the reds got less red, with most now being in the ghastly 625-635nm range, versus the former 640-660nm. It has gotten so bad that I know of at least one supplier which refuses to call the new ones 'red' and lists them as an alternate amber.

[@zinckensteel]

Sounds like you need to find a dentistry college student willing to take a few images of your LED!

[@1marcelfilms]

Can you do a video with the first generation of led lamps for homes.

[@nsfeliz7825]

nakamuras led was the first ec9nomically viable leds.

[@VioletGiraffe]

I like those a whole lot more than the obnoxious modern deep blue LEDs.

[@devicemodder]

Where can i find SiC blue LEDS today?

[@gothesouthway]

Like comparing the wagon wheel to the modern pneumatic rubber tire.

[@SLAPDOORS]

Nakamura basically reinvented the light and got a high five for it lol Man is a legend.

[@FoulOwl2112]

Am l the only one here who kept thinking to himself, "Well as long as we're here. Let's see you light up the other two in the upper right".

[@bside9235]

Just as they did to produce white with the blue one, Why they couldn't do the same to a green led to produce blue ?

[@sjm4306]

I have one or two SiC blue leds somewhere in my collection and they really do have a unique, beautiful color.

[@JohannSwart_JWS]

I far prefer old style LED's for indicator lamps. Most designers run their super-bright LED's way too bright just because they can, even SMD versions. With the exception of lighting applications, this is totally unnecessary. Fortunately I have a good stock of older 80's/90's tech in various colours, which I prefer.

[@Bob-1802]

I use super-bright LED's as indicators because they need a hundred times less current (like 100uA instead of 10mA) to light up decently. On portable equipments, this is a battery saver.

[@glynnetolar4423]

And now...they're TOO bright!

[@smvwees]

In the 80's me and my brother played around with red and yellowgreen leds. They were not super bright. There were also some amber leds and infrared leds. That was basically it at least what we could get in electronic shops then. In the 90's i liked to build a rainbow all with leds from infrared to uv. I found out that i could now buy those babyblue ones you showed as well as newer primary blue leds that were also very bright and cost fl.15,- (like 8 dollars or something). But still no UV. Then a few decades later i also found various UV leds and i am happy now. I only miss out some frequencies like real turquoise colour. Like there are places where there are longer gaps in between readily available wavelenths than that you for instance could buy every led 10 nm apart or even 5 nm apart. But i guess that is to do with the chemical makeup. I hope that one day they also equip computer screens with multiprimary colours of leds, so also yellow orange cyan and violet leds to make an even better Gamut.

[@gorak9000]

Heh, not too many people seem to know about orange LEDs - we had them in high school electronics - just a different color choice on the shelf in our room, but it seems they were pretty rare or something. I know you could run an orange LED by hooking it up directly to a phone line - in a dark room, it gave quite a bit of light. I always though "if you hooked enough of these together, you could make a lightbulb from them - but it would be orange"

[@morgan0]

finally a blue led that doesn’t burn your eyes out by default 😌

[@andymouse]

Here in the UK we had them around the same time and you never forget your first Blue LED ! and yes, they weren't a cheap date ! more than my hourly rate or close ! Awesome side by side....cheers.

[@sdgelectronics]

Those blue and white LEDs were revolutionary. I've got an Nichia white LED that's been running 24 hours a day since 1999 - it's still glowing, but mostly a yellow light now!

[@Graham_Langley]

@@sdgelectronics We bought some 5mm Nichia white ones from RS for something commercial back in 2000 for a fiver each. One ended up as a house number illuminator here, lit 24/7 at around 10mA and was noticeably down on output after a couple of years. Its replacement lasted a lot longer and the current one is still fine after 10-12 years at 20mA although only lit dusk to dawn.

[@AlexanderGee]

I used to be the weird kid who waited for new LEDs to come out. White LEDs blew my mind I don't know how i convinced my mum to spend $20 on one.

[@kapteinsuperskoot6986]

I spent waaaaay too much on the first 2-color/3-color 3-leg LEDs, and on the 2-leg 2-colour ones (polarity dependant). I gave everything in my room lights, and made circuits that *needed* bi-colour LEDs. These new-fangled addressable RGB things just don't grab me like those three-legged wonders. Aah, the nineties...

[@Sonny_McMacsson]

Veritasium: It's seems a bit sciencey.

[@midinotes]

I am sure I can remember buying some of the first 'blue' LEDs, as well as 'white' LEDs. As you say they had a coating over the chip that fluoresced to give white with a hint of blue. They cost several pounds here in the UK, but it was so unique... just as when I bought my first LED torch in the early 90s and still have the silicone PP3 powered PALlight I think it's called.

[@KarlAdamsAudio]

They're absolutely charming, especially when compared to a modern "retina burner".

[@1pcfred]

My computer has a blue LED as a power on indicator and I have two layers of red packing tape over it to reduce the intensity. One layer and it was still too bright. Was actually distracting and annoying. If it hit me it'd give me that star pattern lens flare effect. Like whoah, I'm seeing spots before my eyes! Thing could double as a nite light.

[@gorak9000]

@@1pcfred Or you could just put a resistor in series and knock it back electrically without using packing tape

[@1pcfred]

@@gorak9000 I know that. Two pieces of packing tape was a lot easier for me to do. I like the effect too. I don't like blue LEDs. If I was going to alter the case more I'd have changed out the LED. I'd have probably gone with green. The HDD activity light is red. That'd have been my first choice but it's already taken. Blue indicator lights suck. But it was a trend. One of those bad ideas that many thought was good. Posh blue LED indicator lights.

[@Blank-n7c]

Amazing sky blue leds 💡

[@steveswan5714]

Short but very interesting 👍

[@gamiwv]

Hi John. For more than a week I was seeking for your MUTE/STAN-BY circuit for a stereo amplifier chip and finally yesterday night I discovered it in your video about the TDA7264 . (I'm in the design of a small stereo amplifier with the LM1876 as I have some of them and TDA7379 - not bad at all - but doesn't have "high enough specs" for an close listening amplifier). Thanks for that tiny little board for TDA7264. What is your opinion about p2p (no bred board) realizations ?

[@ericwazhung]

I paged through the Mouser catalog every time it came out, for years, looking for blue LEDs, $6 apiece, as I recall... I bought several on a middleschooler's budget. Was kinda sad they were so dim... but, yes, that color was amazing! I used two, recently, at 30mA each, into a lightpipe on a power button, and it's barely visible in daylight. But oooh that soft color!

[@leon545b]

I remembered getting a sample of the Cree SiC blue LED in 1989 (I don't think I even still have it). I put a comment to that effect on Veritasium's video the other day but got no reply from him or others... Thanks for proving I wasn't crazy!

[@brendajanes4139]

Hi John! Loved your video on these old blue LEDs! I have a fascination with LEDs alone with fluorescent lamps. I still have an early 1940's preheat fixture that still has the original ballast and to this day, still runs just fine. However, getting back to the topic of these blue LEDs, I remember getting some from Digikey myself when these were available. I was surprised that at 20mA, they were not bright. But unfortunately, these did not last very long. I used one in a power supply that I built as a power on indicator, and after a year, I noticed that the light output was reduced significantly. And then a few more years later, the output dropped so much, I could barely see it lighting in total darkness.

[@Muonium1]

These kids today will never know the wondrous glory of seeing your first blue light emitting diode in the 90s. Magical is the only word to capture it! If you want to know today's equivalent of the once coveted blue LED, it's deep ultraviolet UVC LEDs. We can go as low as 250nm now in AlN emitters. They're still horribly inefficient, but they do produce significant amounts of sweet dangerous near vacuum-uv radiation. I just paid about $200 for one in flashlight form for using with fluorescent minerals. Ridiculous and amazing at the same time, just like 450nm blue was 30 years ago...

[@mikafoxx2717]

Wow, 200, and in a flashlight? I'm surprised you need UVC for mineral fluorescence, though I'm impressed you can get them now. I want to see UVA pumped broad phosphors come into normal lighting applications, they have a much better blue spectrum especially for cooler white high CRI lamps.

[@Muonium1]

@@mikafoxx2717 yingfeng sells the UVC leds. I think the next big thing will be 400nm violet laser diode excited phosphor lighting. No current droop like with LEDs and extremely high irradiance.

[@mikafoxx2717]

@@Muonium1 That's my hope! Seoul Semiconductor makes a few violet pumped LED's with virtually perfect CRI. Something like 99 and a 98 R9, and R11 was really good too.