Patent ID: 7326894

Claim:
A heating element for an inside surface of a polymeric front-end module/bumper for a motor vehicle, the heating element being operatively connected to a radar transmitting/receiving unit, the heating element comprising: a heating film formed of at least one of the polymers selected from the group consisting of polycarbonate, polybutylene terephthalate, and cross-linked polyethylene, the heating film having a thickness in the range of about 0.1 to about 0.3 mm; an array of conductor strips integrated into the polymer heating film, the conductor strips having widths in the range of about 0.4 to about 2 mm, the array of conductor strips being divided into an inner region through which a radar beam from the radar transmitting/receiving unit is transmitted, and an outer region through which the radar beam is not transmitted; an electronic control element that controls when the conductor strips heat up the heating film; and connecting pads and an electric circuit adapted to connect the conductor strips and the electronic control element to a power supply of the motor vehicle; wherein the conductor strips in the inner region are uniformly spaced apart at distances ranging from about 2.8 to about 6 mm and are inclined by angles of about 45° to about 90° relative to a polarization plane of the radar beam, and the conductor strips in the outer region are arranged in a meandering pattern and are spaced apart at distances ranging from about 1 to about 6 mm; further wherein a heating output in the range of about 10 to about 150 watts is supplied from the vehicle power supply to the conductor strips, the heating output being electronically controlled by the electronic control element.