To get the technology to work a user has to have a built in camera in their glasses so that when they look down at their hands the device responds due to their hands being mapped as a virtual keyboard they would then use their thumbs to select the keys.
According to the patent that was filed in 2013 to the World Intellectual Property Organisation numbers could be assigned to a forefinger, while symbols could be assigned to a middle finger.
Alternatively, letters could be plotted at various points across the fingers and palm from top to bottom.
Users would then use their thumb to 'press' the various keys on both hands.
The camera would capture the movement of the thumb, or identify the force pressed onto each finger to establish which key had been pressed and type the message accordingly.
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