Phones can recharge while left in the sun

Apr 23, 2007 10:46 GMT  ·  By

Mobile phone manufacturer Motorola has been granted a new patent regarding the use of a mobile phone's LCD as a solar cell. The 'Display and Solar Cell Device' patent would allow mobile phones to come equipped with a solar cell screen that would power and recharge an internal battery while left in the sun.

Now, this wouldn't be the first time manufacturers aimed to solar-power cell phones, but as said before, using sunbeams as the only source for powering the device would be completely inefficient.

In order for the sunbeams to actually reach the device, the user would have to hold it out pointing to the sun. It's even more difficult in this case, as the LCD of the phone would serve as a solar cell, so basically if we're talking about a flip phone (since most of the manufacturer's products come in a clamshell form factor), it would have to be opened as well.

While innovating is always appreciated, just ask yourselves how many times your phone is actually in contact with the sun and not in a pocket or bag.

However, for the time being it's not clear whether Motorola would be using this as the only way to power a phone, or just a spare recharging method that people can use when away from home. Another down side of it would be that the cost of such a dual-purpose display would be quite high. According to Motorola, black-only LCDs would work better in this case, achieving up to a 75 percent light let-through rate.

This is what the abstract includes: Displays such as liquid crystal displays, organic light emitting diode displays and touch sensitive displays are stacked with one or more solar cells such that light passing through the displays will illuminate the light receiving active surface of the solar cells. No reflector or polarizer need be used when the liquid crystal display uses cholesteric or polymer dispersed liquid crystals.