Capacitative sensor assembly

The array (1) has a sensor electrode (2) surrounded by insulating materials arrayed between the electrode and a detection zone. The materials include a plastic layer (10) of a thickness that directly surrounds the electrode and an outer plastic layer (9) of different thickness arrayed at a specified distance. The materials are arranged such that a relative dielectricity constant initially assumes a relatively high value of the surrounding plastic layer, where the constant drops to a value of 1, and again rises to a relatively high value of the outer plastic layer.