摘要 |
<p>Two surface electrodes are applied to an insulating substrate. The surface electrodes are totally surrounded by a metallic shield which is electrically floating, one of the electrodes being an emitter electrode emitting ac radiation and the other a receiving electrode. A portion of the emitted field is conducted by the shield. Upon approach, or touching of the shield by a grounded body, for example by the hand of a user, the field distribution within the shield will change and the radiation received by the receiving electrode will likewise change. In accordance with the present invention, an integrated circuit (IC) evaluation circuit is located beneath the metallic shield on the insulating substrate, the surface electrodes as well as external terminals passing through the insulated substrate being connected to the IC. Preferably, the shield is a plastic cap which is metallized, formed with snap tongs to snap over the insulated substrate.</p> |