Can LEDs generate electricity from light?

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Jon's picture
Jon
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A story on HackADay today is http://abrij.org/~bri/hw/sunflop.html where he uses LEDs as photo sensors. The questions on HackADay wonder if LEDs can sense light. I'm guessing that if you shine photons on the doped silicon you might cause it to emit an electron, opposite of how LEDs work, right? Basically they might work as a really weak solar cell?

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herrhanz's picture
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It's possible...

It's possible... only it would be a very very very weak solar cell.

Hans

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I dunno, I find this cause fo

I dunno, I find this cause for extreme skepticism. I have some pretty sensitive instruments. I'll try it out and get back to you.

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Eudimorphodon's picture
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Not enough of an engineer to know, but...

From my vague understanding of the subject I have this feeling a diode would behave more like a single-element CCD then a solar cell. In which case you would get a "charge" you could read off it, but no useful current flow. But then, that's a wild guess based entirely off of the descriptions in the manuals of the "Science Fair 200 in 1" electronic kits I had as a kid.

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It will generate a small curr

It will generate a small current as one very simple transmitter and reciever you can build consits of 2 IR leds, one as a transmitter and the other as a reciever.

Also, if you saw the top off a metal cylinder type transistor, that will act in a simular way...

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DrBunsen's picture
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well...

Funny you should mention that... links in this forum thread lead to much info and hackage on this subject

A solar cell is a diode - the light excites electrons to wander about and a p-n layer makes them wander one direction and not the other. Viola, useable current.

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simon_C's picture
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does this answer your questio

does this answer your question?

thats a green laser

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coius's picture
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Welp,

Guess that solves that....

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Jon's picture
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Sweet! Did you hook up a DVM

Sweet! Did you hook up a DVM to get a reading of the output?

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not my pic.... http://safeco

not my pic....
http://safeco2.home.att.net/laser.htm got it there

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