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OLEDs May Generate Electricity
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...'"
How well do these work when compared to traditional Solar Cell based components? With the addition of a few capacitors, it would be nice to have OLED lighting which would recharge during the day.
The solar-powered flashlight is finally a reality.
Karma: Good (despite my invention of the Karma: sig)
--Mike--
LED's have supposedly 100,000 hours of use in them. of course, that's at about half intensity, and they still dim over time, and it's not been fully proved (LED's haven't been mainstream for 10 years really)....
OLED's supposedly have somthing like a maximum of 30,000 hours of life.... would using them as primitive "solar cells" decrease their lifespan considerably? or is this a possible reason as to why they have such a short lifespan?
on a somewhat completely unrelated topic, if increasing battery life is so damn important, why haven't they started including $3 radio shack 3v solar panels on everything in existance? or does the voltage/amperage have to be >= standard voltage of the battery? we have a 200mA trickle charger for our 12v deep cycle boat battery...
would i be able to run/charge my m100 off a $3 3v solar cell? if i underclocked it? yes, i realize it's usually in my pocket....but it does sit underneath a hallogen light when i'm @ the computer...
moox. for a new generation.
So not only will we get better displays for out PDAs and laptops, but then they can be charged a bit while off.
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Never underestimate the power of stupid people in large groups.
could the generated voltage damage the display parts?
ex: you turn off you oled monitor and the sunlight
overtime kills the powersupply for the monitor
Now it becomes really easy to implement some sort of light pen device. Also, how about a screen/scanner combination?
Free, as in your money being freed from the confines of your account.
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
Read the article
It says that to generate electricity it needs to be formulated differently.
So you get a display or a solar cell, not both.
But, maybe they can work on an new proccess that does both.
It was Big News earlier this year when an organic solar cell broke the 2% efficiency barrier (though it's still below 2% for sunlight.) And that's with a material specifically engineered to be an efficient solar cell.
This stuff, optimized to shine light rather than absorb it, is probably considerably less efficient. Maybe by an order of magnitude even. Combine that with the impracticality of charging your laptop even with commercial solar cells, and you've got a non-starter. Perhaps after several more generations of research this will have some use, but not now.
has anyone considered coating the laptop case with this, it would not produce enough electricity to run a lap top, but you do not use a lap top 24 hours a day, surely this would help to increase the length of time needed between recharging.
Douglas-Martin sunscreen's from Heinlein's stories?
IIRC, their functionality was based upon the firefly's light reaction.
"'Tis great confidence in a friend to tell him your faults, greater to tell him his." --Poor Richard's Almanac
Take a yellow or green LED and shine your handy-dandy green laser pointer ($150 @ thinkgeek, support your sponsors!) directly into the lens. You get a little over 1VDC output from the LED, but only a few milliamps of current.
I learned this trick from this page at the LED Museum. Theres a picture of this stunt there as well.
This story seems newsworthy because it's nifty new OLED properties, but it's not really news that you can get an LED to rectify some electrons out of a light source.
In the same way that a speaker will work as a microphone?
Just because it's possible doesn't make it a good idea or even news...
I am a Karma Library.
Hopefully they don't work too well. Otherwise a flash photograph could fry the display chip on OLED using pdas. I guess they might need to start surge supressing the display.
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--
Efficiency is only part of the issue. The other is expense and difficulty of manufacturing. If it's less efficient but cheaper, it's still viable.
"According to Stewart Hough, vice president of Business Development, the polymer materials need to be formulated differently than for displays"
In the event of an emergency, your screen will not act as a flotation device.
Does anybody know how expensive OLEDs are? If they can be sprayed on using inkjet printing procedures, could I just paint my whole house (or at least my roof) with them? Probably wouldn't power much, but it couldn't hurt...
LED's will too, it's just a Diode. Just like Solar Cells. They are made differently though cuz the solar cell needs to have a large surface area to be efficient, the [O]LED is designed as an emitter, it doesn't. (They also use different materials for different bandgaps & hence color.)
OLEDS and Organic Photovoltaics are obviously based on similar designs, but there are optimized differently. This is clear since OLEDS are meant to emit one wavelength only, where the ideal solar cell absorbs as many wavelengths as possible. The highest solar efficiency reached with organic solar cells are 3 and 4.5 for polymer based and organic crystal based, respectively. In the end, the overall efficiency is NOT the point... although the best single crystal inorganic solar cells have efficiencies of over 20% (yes, check... GaAs thin films, used in space), they are extremely expensive. What makes Organic solar cells attractive are the fact that they don't need elaborate fabrication (theoretically), and thus will cost more than 4 times less... so for large scale applications one can just install more than 4X the solar cells for less money. Obviously this doesn't help those who want to power their laptops out in the middle of the desert, but when it comes to scaled economic viability, they are still relevent. Hence why so many people are working on them.
you can also use your kitchen sink as a toilet... This is basic electronics, perhaps an article should be run that the earth really isnt flat...Boring Why is the quality reporting going down the 'kitchen sink'?
This could be very useful for creating optically isolated bi-directional interfaces. Right now, when designing a circuit you would use one optoisolator per signal and it would be one direction only.
This also could be really cool for fiber optics. Instead of having to run one fiber for tx and one for rx you could just run one fiber and switch the led between a tranmitter and a reciever. Do OLED laser diodes exist?
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