Patent ID: 7617729

Claim:
An accelerometer comprising: a) a planar substrate having an upper surface and a lower surface, b) a proof mass having at least a portion disposed within a principle plane parallel to the plane of the substrate, and further comprising; i) at least one support beam disposed parallel to the upper surface of said planar substrate, ii) a first plurality of branched electrodes, which comprise; (1) a plurality of support arms extending laterally from the at least one support beam, (2) a plurality of movable electrode plates distributed along each of the plurality of support arms, the plates being disposed perpendicular to the upper surface of said planar substrate, c) a plurality of folded springs coupling said proof mass to said substrate for confining the movement of said proof mass in a plane parallel with the plane of the substrate and in the direction parallel to the plane of the movable electrode plates, d) a second and third plurality of branched electrodes coupled to said substrate, each branched electrode comprising; i) a plurality of static electrode plates distributed along the branched electrodes, the static electrode plates being disposed parallel and interlaced in capacitive communication with the movable electrode plates and perpendicular to said substrate, e) wherein at least two pairs of capacitors are defined by the electrical communication between the static electrode plates on the second and third plurality of branched electrodes and at least a portion of the first plurality of electrodes on said proof mass wherein alternating adjacent branched electrodes on the proof mass are electrically isolated to form a first and second subset.