US Patent 9479875 Multi-mode microphones

In some embodiments, a sensor system may include a deformable structure and a sensing element. The deformable structure may include at least one layer of piezoelectric material and at least one actuator port disposed on the at least one layer of piezoelectric material. The deformable structure may deform in response to external phenomenon. The at least one actuator port may be configured to actuate the at least one layer of piezoelectric material via application of an electrical signal to the at least one layer of piezoelectric material. The at least one layer of piezoelectric material may be configured to apply a force to the deformable structure when actuated. The sensing element may be configured to sense deformation of the deformable structure capacitively, optically, or via a sensing port according to embodiments.