The traditional form of the bifocal consists of two glass pieces, each with a separate index of refraction.
The top of the glasses still function as a typical far-focusing prescription lens, but the bottom half has an electro-active liquid crystal in it. When an electrical current is applied, the lens will change its refraction index, allowing near-focus objects to be easily seen while simultaneously using the properties of science by “freezing”the lens into a particular curve.
The glasses come with three settings – active on, manual on, and manual off, all flipped through easily by the press of a switch located on the side of the glasses. The manual off setting will leave the bottom layer free of current, and it will act like a low-power progressive lens which is useful for activities of daily life.
The true proof of concept comes with the active on mode. When the glasses are turned on, an electrical current is supplied to the business end on an intermittent basis. The glasses will be powered by a rechargeable battery that will regain energy when the bifocals are placed in aspecial cradle. This charging process should take two to three hours and the charge will last for up to five days.
The emPower! is scheduled for a 2010 release in the United States and 2011 in Europe.
With my lagging eyesight, I would get a pair :o)
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