The shape of a three-dimensional object is determined from uncalibrated stereo images by first determining the projection of the point on a reference plane. Herein the first electrode includes: a first layer including a material having a work function of about 4. This invention teaches the use of miniature electrical stimulators that can be implanted alongside the injured nerve at the time of surgical repair and that can be powered and controlled by transmission of radiofrequency energy from outside the body so as to provide a variety of electrical stimuli at different times during the recovery process. For example, one transducer device may be used for both two-dimensional imaging and three-dimensional imaging in response to the one-dimensional array and multi-dimensional array electrode configurations. Characterization data is input for each configuration control module specifying a first ordered set of address output pins and a second ordered set of data output pins.