Coordinate input device with display.

摘要

A coordinate input device with display comprises a tablet (100) having a plurality of X-direction magnetostrictive transmission mediums arranged in parallel, a plurality of Y-direction magnetostrictive transmission mediums arranged in parallel and superposed on the X-direction transmission mediums substantially orthogonally thereto, and first and second coils arranged over substantial regions of the magnetostrictive transmission mediums. The device further comprises a plurality of biasing magnetic bodies adapted apply a biasing magnetic field to the portions of the magnetostrictive transmission mediums surrounded by the first and second coils, and a tabular display (300) superposed on the tablet (100) and having a display area substantially equal to the position detection area on the tablet (100). A position appointing magnetism generator (200) such as a magnetic pen is capable of producing a magnetism just enough for causing a local increase of electro-mechanical coupling coefficient in the magnetostrictive transmission mediums in the tablet(100). The device further comprises a position detecting circuit (400) adapted to supply a pulse current to one of the first and second coils such as to generate magnetostrictive vibration wave in a reference position on each magnetostrictive transmission medium or a position appointed by the position appointing magnetism generator (200. The position detecting circuit (400) being further adapted to measure the time duration between the moment at which the magnetostrictive vibration wave is generated and a moment atwhich the magnetostrictive vibration wave has reached the appointed position or the reference position, thereby detecting the coordinate values of the position appointed by the position appointing magnetism generator (200). A display control circuit (500) drives the display (300) in such a manner that the position corresponding to the coordinate values is displayed on the display (300). A modulating/demodulating circuit (700) is adapted for converting the position data expressed by the coordinate values into a signal suitable for transmission through a transmission line, and vice versa. The operation of these circuits is controlled by a processing circuit (600). Appointment of coordinate position is made by the position appointing magnetism generator (200) from a position above the display (300), through the display (300) which is superposed on the tablet (100), and the position thus appointed is displayed on the display for visual check. The coordinate position information thus obtained is transmitted to a remote station through, for example, a telephone circuit (900) and is displayed on the display of theremote station. Since the position appointing magnetism generator (200) is not connected by cord to stationary part of the device, the position appointing operation and the visual check of the display (300) can be made easily without being hindered by the cord.