Patent ID: 8079262

Claim:
A pendulous accelerometer comprising: a) a substrate having a substantially planar upper surface; b) a sensing plate having a central anchor portion supported on the upper surface of the substrate to define a hinge axis, the sensing plate including a solid proof mass on a first side of the central anchor portion and a substantially hollow proof mass on a second side of the central anchor portion, the solid proof mass having a first lower surface with a first electrode element thereon, and the substantially hollow proof mass having a second lower surface with a second electrode element thereon, wherein the sensing plate is mounted to rotate about the hinge axis relative to the upper surface of the substrate in response to an acceleration of the proof masses, wherein the substantially hollow proof mass and the solid proof mass are connected to the central anchor portion by torsion bars, wherein the lower surface of the solid proof mass and the lower surface of the substantially hollow proof mass are coplanar with respective lower surfaces of the torsion bars, and wherein respective upper surfaces of the central anchor portion, the torsion bars, the hollow proof mass side and the solid proof mass side of the sensing plate are coplanar with one another; c) a first electrode section positioned on the upper surface of the substrate beneath the solid proof mass to interact with the electrode element on the lower surface of the solid proof mass; and d) a second electrode section positioned on the upper surface of the substrate beneath the hollow proof mass to interact with the electrode element on the lower surface of the hollow proof mass.