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Why It Was Almost Impossible to Make the Blue LED (youtu.be)

submitted 9 months ago by [email protected] to c/[email protected]

208 comments fedilink hide all child comments

The blue LED was supposed to be impossible—until a young engineer proposed a moonshot idea.

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[–] [email protected] 10 points 9 months ago (3 children)

I freaking hate blue LEDs.

I actively avoid buying anything with a blue LED because they are so obnoxious. So bright. Why do I want to read by the light of my HDD? Does this video explain why they have to be like that?

Maybe if you have a separate wing of the mansion to do computing stuff it is not annoying. But if like a lot of people you have electronics in your living space, these lights are extremely disruptive.

It seems that can't really be dimmed.. I had to give up on a couple of blue backlit alarm clocks because there is no way that the time can be visible without illuminating the whole area around them.

For whatever reason, red is the best one. I would prefer another color aesthetically. For whatever reason, red is the only color that does what it has to do and nothing more.

[–] [email protected] 21 points 9 months ago (1 children)

If you own anything with "white" LEDs, I have some bad news for you...

[–] [email protected] 9 points 9 months ago* (last edited 9 months ago) (1 children)

Or reading this on anything except an e-reader or if someone else printed it out on a printer without blue leds first.

[–] [email protected] 1 points 9 months ago

Luckily my device screens can all be turned off, closed, put face down and otherwise turned off when not in use. Unlike indicator lights on the routers, APs, HDDs, PCs, mice, powerbars, extension cords, radios, headphones, USB cables, ACs, microwaves etc etc etc. Either totally unnecessary to have a light in the first place, or a subtle light could do the job just as well.

[–] [email protected] 17 points 9 months ago

This is actually a biological phenomenon that most humans experience! Our eyes are more attuned to greens and blues rather than reds, so green and blue light appear brighter as the cones in our eyes are more sensitive to those colors. Similarly, our cones are less sensitive to red so it appears darker.

There's also a physics component to this as well since red light has about half the energy (twice the wavelength) as blue light. However, since there's a difference in energy, the engineer must take that into account when designing multicolor LED applications so as to keep a level light intensity when changing or blending colors.

Here's an eli5 question with some more info: https://www.reddit.com/r/explainlikeimfive/comments/ghx9g6/eli5_why_does_red_light_seem_darker/?rdt=58820

[–] [email protected] 3 points 9 months ago

I'm the guy that takes an awl and literally shatters them, or I will just place tape over top if they are recessed too far.

Front facing LEDs are a menace.