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Comment Re:Somewhat off-topic: why not uncut LED panels? (Score 2) 93

They would be too bright, and too expensive. Those 5mm LEDs (outdated crap) have LED dies of a less than 1/20th of a mm^2 inside.

High-end power LEDs that put out the equivalent of a 100W incan bulb are 2-4mm^2.

A disk the size of a traffic light would be able to draw 10000s of Amps, and be bright enough to illuminate a stadium (if you could drain the waste-heat away). Driving it with lower currents would be a collosal waste of dies.

So the wavers are cut into conveniently sized pices that have reasonable power draw and thermal conductivity and then later are put together according to the requirements.

Comment 25 year old technology (Score 1) 93

Not just the production way is low-tech, this type of LED is depricated for everything but the cheapest crap available.

Modern LEDs are basically all SMD, the high power ones typically mounted on a solid metal core PCB. And those are acutally manufactured in a more modern type of way.

Comment Re:volume (Score 1) 193

There isn't that much to gain from economy of scale, as those types of cells are already produced in 100s of millions per year. So we are realistically looking at something like halfing the price at most, not cutting it down by an order of magnitude or something.

Comment Re:Impressive. (Score 1) 410

Wrong. Per default, Autobahn has not speed limits.

Unless indicated otherwise, if you enter the autobahn, NO LIMIT.

Yes, there are speed limits quite commonly, but if you discount Stadtautobahn stuff and the Ruhrpott, 2/3rds of it are unlimited. Case in point: You can drive Stuttgart/Berlin and have all but 50km or so of the distance unlimited.

Comment Re:Great... (Score 1) 297

In theory. In practice, helium will interact with, for example, iron alloys (steel), ending up with de-electonized protons migrating through the bulk metal, and at the other end snatching up some of the fermi-gas and going their merry way.

The same way, in vacuum systems, getting rid out of the stupid hydrogen magically appearing out of nice stainless steel enclosures that have been ultrasonic cleaned and baked under vacuum is a real problem. I have seen suggestions of burning the whole chambers under vacuum at 650C to get the protons out, and even that isn't really the end of things.

Comment Re:Uses of Java applets (Score 1, Insightful) 362

Are you posting in Bizarro land?

Your own link tells us that over 91% of the users of chrome didn't even encounter a SINGLE java applet in a whole MONTH.

Thats an absolutely overwhelming sign that java is almost extinction-level rare in the web. Hell, I would bet that the rate of people encountering embedded MIDI files was much higher.

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