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Solar-Charged Phones Without A 93-Million-Mile Cord

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Solar-Charged Phones Without A 93-Million-Mile Cord


Solar-Charged Phones Without A 93-Million-Mile Cord

Solar-Charged Phones Without A 93-Million-Mile Cord

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  • <iframe src="" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
  • Transcript

Researchers have found a way for LCD screens to charge using solar power, indoor light and the devices' own backlight. That means in a few years, you may be able to recharge your phone by pointing it toward the sun instead of plugging it into the wall. Guest host John Ydstie talks to the lead UCLA researcher, Yang Yang.

JOHN YDSTIE, host: It's probably happened to you. Your phone, laptop or iPad is running out of power and you've left your charger at home or you're too far from an outlet and the screen goes black until you can plug it in again. But what if you could power up just by turning the screen toward the sun or an indoor light? That day may not be far off, thanks to a team of researchers at UCLA, led by Professor Yang Yang. He joins me now from UCLA. Welcome to the program, professor.

YANG YANG: Thank you.

YDSTIE: So, explain to me how this technology that you've developed would work.

YANG: All these electronic gauges have display, and a display typically we call LCD or liquid crystal display. It works like there are two pieces of polarizers that filter the light and then the liquid crystal molecule work as a switch to turn the light on and off. And the polarizer is unfortunate a very energy-inefficient device. They automatically filter or cut off 50 percent of the light - that's how it works. So, our invention is to recycle that light has been wasted during the process.

YDSTIE: So, you're actually going to recycle the light that's been given off by the screen but wasted.

YANG: That's part of the function, yes. But in the meantime, as you described earlier, we can actually position the device under the sunlight or room light. So, it behaves as a solar cell, which can generate electricity from the light externally.

YDSTIE: And charge the battery in that way.

YANG: Exactly.

YDSTIE: What kind of consumer device would be best suited for this technology?

YANG: Any device that requires a display. For example, the iPhone or even the desktop monitor or LCD TV. So, those devices or displays requires polarizers can actually utilize our invention.

YDSTIE: How close is this technology to making its way to the market?

YANG: I hope that technology can reach the market in the next five years, but it's very challenging because of the technology's successful in the laboratory compared to commercialization is a complete different approach.

YDSTIE: What are the major obstacles that you need to overcome before it comes to market?

YANG: If you look at the TV or your cell phone image, they are pretty high quality today. And some of them, even 3-D quality. We don't want to downgrade the image quality. So, that's the major challenge that I can imagine.

YDSTIE: Professor Yang Yang teaches material science at UCLA. Thanks for being with us.

YANG: Oh, you are very welcome.


YDSTIE: This is NPR News.

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