US Patent 9329720 Digitizer

A system for receiving, storing, and displaying biometric input has a case, a touchpad, and a digitizer. The case has an open position and a closed position, wherein the case protects the touchpad in the closed position, the case including a digitizer comprising a substantially transparent touch activatable overlay placed over the touchscreen, and a plurality of sensors supported by the overlay to detect input to the overlay. The digitizer includes a data outlet for transferring the detected input as overlay data so the touchpad can visually display the detected input on its touchscreen. The digitizer has sufficient sensors that the overlay data contains more information than the touchpad data would if the touchscreen were contacted directly without the digitizer present.