Ostrager, Chong & Flaherty
Wireless input system for computer using elevated four-division photodetector
 A wireless input system for a computer includes a pen-type input device and an input device body. The pen-type input device comprises a light emitting element for emitting a pulse of light. The input device body comprises at least one optical system unit including a light receiving element for receiving the pulse of light emitted from the light emitting element of the pen-type input device and a circuit for calculating the outputs from the light receiving element to obtain the position abscissa of the pen-type input device. 
Data Stream Corporation
G G
G06F G06F
inventional inventional
Hideo Manabu
Goto Fujita