Patent ID: 8274724

Claim:
An actuator device, comprising: a support base; a first flexure including a first flexure base that is fixed to the support base and first flexure extensions that flex with respect to the fixed first flexure base and the support base; a second flexure including a second flexure base that is fixed to the support base and one or more second flexure extensions that flex with respect to the fixed second flexure base and the support base, the second flexure positioned and oriented to have the first and second flexure extensions to cross; an actuator engaged to distal ends of the first and second flexure extensions to rotate around a single rotation axis as the first and second flexure extensions deform when the actuator is actuated to rotate, the actuator being electrically coupled to the first flexure extension to receive an electrical actuator drive signal through the first flexure extension to cause the actuator to rotate and to maintain at a position; a mirror engaged to the actuator to move with the actuator and stay with the actuator; a conductive sensing plate fixed to the mirror or the actuator; a capacitor sensing device fixed in position relative to the support base and including two electrically conductive plates separated from each other to form a gap into which the conductive sensing plate is partially inserted; a third flexure comprising a third flexure base that is fixed to the support base and a third flexure extension connected to the third flexure base at one end and connected to the conductive sensing plate on the other end, the third flexure forming an electrically conductive path that is electrically isolated from the first flexure and the electrical actuator drive signal therein; a position sensing circuit coupled to the third flexure to apply an electrical sensor signal which is conducted to the conductive sensing plate, the position sensing circuit including a processing circuit that receives first and second electrical signals from the electrically conductive plates and produces a position signal from the received first and second electrical signals indicating a relative position of the conductive sensing plate relative one of the electrically conductive plates; and a servo control circuit coupled to the position sensing circuit and the actuator, the servo control circuit operable to produce a servo control signal based on the position signal and operable to control the actuator based on the position signal.