(EN)
A user input system ( 1 ), comprising a coil ( 44 ) for generating an alternating magnetic field, a cordless pen ( 9 ), and a capacitive current measuring arrangement or an electric field sensing arrangement. The cordless pen ( 9 ) comprises a resonant circuit ( 34 ), a conductive housing ( 28 ) and a conducting tip ( 36 ). The alternating magnetic field induces an alternating voltage in the resonant circuit ( 34 ), which is coupled to the conducting tip ( 36 ). The capacitive current measuring arrangement comprises a resistive sheet ( 40 ) and current measuring means ( 42 ) arranged to measure a capacitive current flowing from the conducting tip ( 36 ) to the resistive sheet ( 40 ). The electric field sensing arrangement comprises an electric field sensing reception electrode ( 47 ) and current sensing circuitry ( 48 ) for determining a current excited in the electric field sensing reception electrode ( 47 ) by an electric field generated by the conducting tip ( 36 ). In each case the currents are sensed at plural locations and the differing magnitudes compared to determine a position of the conducting tip ( 36 ) relative to the plural locations. The system may also be adapted to sense a user's finger ( 8 ). The user input system ( 1 ) may be incorporated in a display device, for example an active matrix liquid crystal display device ( 4 ).
(ZH) 用户输入系统(1),包括用于生成交变磁场的线圈(44)、无绳笔(9)以及电容电流测量装置或电场感测装置。无绳笔(9)包括共振电路(34)、导电壳体(28)以及导电尖端(36)。交变磁场在共振电路(34)中感生交变电压,该共振电路(34)与导电尖端(36)耦合。电容电流测量装置包括电阻薄层(40)和电流测量装置(42),该电流测量装置用于测量从导电尖端(36)流到电阻薄层(40)的电容电流。电场感测装置包括电场感测接收电极(47)和电流感测电路(48),用于测定电场感测接收电极(47)中由导电尖端(36)产生的电场所激发的电流。在每种情况下,在多个位置上感测电流并且比较不同的大小以测定导电尖端(36)相对于该多个位置的位置。系统也可以适于感测用户的手指(8)。用户输入系统(1)可以合并到显示设备、例如有源矩阵液晶显示设备(4)中。