Digitising table with projected keyboard or screen

The digitising table is produced from a surface plate of wood or plastic and beneath it is a layer containing the coils and wires of the position detection system. The table surface plate is of a thickness so a hand held probe can be detected by the sensors. A keyboard or computer monitor screen is projected onto the surface of the table and a cursor moved by the probe. Pressure sensors on the position probe sense further parameters, e.g. the x, y and z coordinates of the probe position for input to the computer screen.