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OLEDs May Generate Electricity

Posted by timothy on from the another-step-toward-off-grid-computing dept.

NewmansDaddy writes: "According to a PCMag article, 'When the OLEDs are working as a display, you apply electricity to the materials and they emit light. It turns out, however, that if you apply light to these devices, you can get them to produce electricity; in other words, they will run backward...'"

3 of 43 comments (clear)

  1. So??? by ka9dgx · · Score: 4, Informative
    LEDs are also photoelectric. I built a sensor with two of them, one as a photodiode. I did this 8 years ago, for fun while visiting my friend in Florida.

    --Mike--

  2. Ah, photonics by Yarn · · Score: 5, Informative

    A friend of mine has been working on organic solar cells for the last 4 months (MSc Project), he's hoping to reach 4% efficiency. Last time I spoke to him he was just about to put the ITO transparent contacts on, then test it with different wavelengths of light.

    The possibilities of making organic solar cells have been considered almost as long as organic LEDs have been known (one of my professors was in the Cambridge group who discovered the effect) but the efficiency will probably never be near that of good polycrystaline silica.

    To power my laptop I'd need half a metre square of high grade solar cell, about £500...

    --
    -Yarn - Rio Karma: Excellent
  3. photoelectric LEDs by ka9dgx · · Score: 4, Informative
    LEDs are clearly PhotoElectric. They do generate measureable (but only slightly useful) amounts of current in response to incident light.

    They are also spectrum sensitive, picking up only equal or higher energy photos. This can be verified with a microAmp meter, and a set of various high-brightness LEDs. You'll observe that a red LED will pick up red or shorter wavelengths, green only detects green and shorter wavelengths, etc.

    (Red has the longest wavelength (and smallest energy per photon) of visible light, violet is the shortest wavelength, and highest energy photon.) The high energy of blue is why it's been so hard to make a blue LED for years.

    Put them face to face, run the source LED at its rated current, and expect a few microAmps out of the other LED..

    --Mike--