Why all solar panels are secretly LEDs (and all LEDs are secretly solar panels)

Part 2 – explainer video is here:

LEDs and solar panels are both made of diodes. A diode is just designed to allow electricity to flow in one direction but because we make them out of semiconductors they can do all these other things.

Video produced in cooperation with Merck ( Merck is known as Merck KGaA, Darmstadt, Germany in the United States.

Here’s the link to the curiosity report (interactive):

And here it is as a PDF:

Animations by Dom Burgess. His brilliant channel, Every Think, is here:

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  1. same as i know from a 40 years ago, where you could remove the top of a metal cased transistor with a file
    and then use it as a solar cell as for example, the principle is similar , also as a Opto-coupler , optec , the optical input etc.

  2. I didn´t know this! I would have been exited to find light emitting solar panels and sound receiving speakers myself

  3. Everyone thought I was crazy when I started speaking on my apple earphone (the right speaker specifically), rather than the microphone part itself.

  4. I'm an electrical engineer. You can use many kinds of microphones as speakers, but not all. Condenser microphones, which use capacitance, won't function as a speaker. Virtually all speakers can be used as microphones.

    Speakers usually use magnetism. Some crude speakers use the piezo-electric effect. Both of those will work in reverse as microphones.

  5. Et tu brute ?
    You too brutus ?

    Some youtubers are real
    some youtubers are good
    Some youtubers are fake

    Some youtubers are real good at beibg fake


  6. This reminded me of when a friend and I accidentally plugged the headphones into the mic jack and learned it worked as a mic.

  7. So how long will it take to Charge a small aa battery if you used LED lights set as an array to charge the battery from the sun ?

  8. Seems science often works transversely. I have seen that when you put two full glasses of water side by side and put a positive electrode in one glass and a negative in the other, a bridge of water is formed between the glasses and wondered if there is a way this could work transversely?

  9. This somewhat explains a phenomenon I experienced with my led flashlights. When I take the lens off of my Emisar D4S and get in close on the chips with an olight uv flashlight, the other chips on the emisar begin to glow on their own. No battery in the flashlight. Very cool

  10. Me as a photography student watching this guy film dust enter his sensor on a digital camera: AAAAAAAAAAAAAHHHHHHH

  11. Conclusion:
    Solar panels takes more energy so not used as LED
    LED gives very low voltage so not used as solar panel

  12. Would you please speak faster, and stop assuming we're all Obama sycophants? ie: we don't need tiny phrases to understand a concept.

  13. I do this every day at work – load up a module into the (pitch black) EL chamber and run a current through it, and use a camera with special aperture and exposure/ISO settings to capture the pattern and check for any cracks. They become very obvious under these conditions. Oddly enough, some of the extremely cracked modules sometime still produce an OK amount of power. Depends on how the damage happens.

    If you have solar panels, clean any leaves that fall on them. If they shade the exact percentage of a cell needed to cause a 'kink' in the electrical flow, heat builds up and it can literally catch fire. We do a test called the "hot spot" test that puts various sizes of square tape over a section to find the magical % of a cell that causes the "kink" so the manufacturer can put it in their specs/manual.

  14. And why LED lights suck as nd why saving energy is over rated when fixture blinks signaling the end of it's useful life cycle.

  15. I never understood why microphones and speakers were like that, but I came across it on accident, finding that a mic works as a really crappy speaker.

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