| 摘要 |
A proximity sensor 300 comprises a transmit electrode 320 disposed on a first major face of a substrate 310, the opposite major face having spaced apart first and second receive electrodes 330A,B and a ground shield portion 340 disposed between the receive electrodes having at least first and second elongate electrode portions defining a first region. A radio frequency signal is applied to the transmit electrode to generate an electric field 350 and cause an RF signal to be induced in each receive electrode, the strength of which being dependent on the relative distance of a conducting object. The ground shield portion may encompass the first region, which may comprise an aperture 315. The sensor may comprise a first axis L passing through the receive electrodes and a second orthogonal axis W passing through a further pair of receive electrodes 330C,D arranged on opposite sides of the first region. An optical communications transmitter and/or receiver 380 may be disposed through the aperture 315. A controller 300C may apply an RF signal to the transmit electrode and provide an output signal indicating the relative RF signal strength in the receive electrodes. The sensor may be provided in a vehicle (figure 5). |
