Capacitive detection device and system for use in vehicle interior

A capacitive detection device for use with a component of a vehicle interior, comprising:

• at least one electrically conductive wire disposed beneath an outer surface of the component of the vehicle interior and arranged to extend in a direction substantially parallel to an outer surface of the component of the vehicle interior,
• a signal generating unit configured to generate and apply a time-varying output signal to the at least one electrically conductive wire,
• a signal evaluation unit configured to sense a change of an electrical quantity that is indicative of a change in capacitance of the at least one electrically conductive wire, and to generate an output signal that is representative of the sensed change of the electrical quantity,
• at least one electrically conductive layer arranged substantially parallel to at least a portion of the outer surface of the component of the vehicle interior and positioned with respect to a direction perpendicular to the outer surface of the component of the vehicle interior either above or below the at least one electrically conductive wire, and arranged to at least partially overlap the at least one electrically conductive wire in a direction perpendicular to a portion of an outer surface of the component of the vehicle interior that is closest to the at least one electrically conductive layer, wherein a galvanic connection between the at least one electrically conductive layer and the at least one electrically conductive wire is avoided,
• wherein at least a major portion of the at least one electrically conductive wire is arranged with respect to the at least one electrically conductive layer and the outer surface of the component of the vehicle interior such that a ratio R≥2, wherein R is given by:
• R
• =
• min
• ⁡
• (
• d
• ⁢
• ⁢
• 2
• ,
• d
• ⁢
• ⁢
• 3
• )
• d
• ⁢
• ⁢
• 1
• ≥
• 2
• wherein d1 is a minimum distance taken at a location where the at least one electrically conductive wire is closest to the at least one electrically conductive layer, d2 is a minimum distance taken at a location where the portion of the outer surface of the component of the vehicle interior is closest to the at least one electrically conductive layer, and d3 is a minimum distance taken at a location where the portion of the outer surface of the component of the vehicle interior is closest to the at least one electrically conductive wire.