Eddy current sensor arrays having drive windings with extended portions

A test circuit comprising:

• a primary winding loop of conducting segments having an extended portion and a return portion to impose a magnetic field in a test material when driven by an electric current;
• and
• a first plurality of sense elements for sensing a response of the test material to the imposed magnetic field, said sense elements being positioned inside the primary loop near said extended portion and farther from the return portion, the sense elements being aligned with one another to sense the response at incremental areas along a path parallel to the extended portion of the primary winding and having separate output connections.

A test circuit comprising:

• a primary winding loop of conducting segments having a pair of parallel extended portions to impose a magnetic field in a test material when driven by an electric current;
• a first plurality of sense elements positioned closer to one extended portion of the pair of extended portions, each having separate output connections, for sensing a response of the test material to the imposed magnetic field, the sense elements being aligned with one another to sense the response at incremental areas along a path parallel to the extended portions of the primary winding, and a width of a sense element being smaller than a spacing between the parallel extended portions.