Capacitive touch entry apparatus having high degree of personal safety

Claim 1

A touch entry panel activatible upon contact by a user member, comprising: a relatively thick insulative substrate having a first surface contactable by user personnel, and a second surface opposite said first surface, with both said surfaces being devoid of operational elements of said panel; a single member having a single insulative layer with a first surface and a second surface opposite said insulative layer first surface, and having all electrodes of at least one capacitive touch sensor formed completely thereon; each capacitive touch sensor comprising a touch electrode fabricated on said insulative layer first surface and a pair of spaced-apart electrodes fabricated upon the second surface of said insulative layer and in registration with the touch electrode of that sensor; a terminal associated with each of said spaced-apart electrodes; lead means fabricated upon said insulative layer second surface for interconnecting each of said spaced-apart electrodes and its associated terminal; conductive guard means disposed upon said insulative layer first surface and positioned for shielding the lead means of at least one of said at least one capacitive touch sensor from capacitive effects when said substrate first surface is contacted by said user member; and means for fastening said member first surface adjacent to said substrate second surface; said substrate being formed of a material having a dielectric constant sufficiently high enough to cause one of said at least one capacitance touch sensor to be activitated when the user member contacts a portion of the substrate first surface opposite the touch electrode of the capacitive touch sensor to be activated.