Feature extraction as a tool for computer input

This paper describes a versatile human-machine interface designed to achieve an important balance between human factors and flexibility. It incorporates attributes of keypads, tablets and ´mice´ and possesses freedom of keyshape, size and function. The system uses a TV camera focused on a ´keyboard´ area to generate electrical signals in response to optical inputs. Additional optical and electronic feature extraction result in an input device capable of processing discrete and continuous input simultaneously.