Multilayer eddy current probe array for complete coverage of an

Abstract

An eddy current surface measurement array structure for complete coverage of an underlying inspection surface without requiring mechanical scanning is disclosed. A three-dimensional array of eddy current sense elements is organized as a plurality of layers of two-dimensional sub-arrays. The sub-arrays, although in different layers, are essentially identical in configuration, and are staggered such that the sense elements of one layer provide at least partial coverage of portions of the inspection surface not covered by the sense elements of another layer. As many staggered layers are included as are necessary to ensure that no 'blind spots' remain, for complete coverage of the underlying inspection surface. The sense elements are disposed in a layered flexible structure fabricated employing high density interconnect fabrication techniques or other photolithographic techniques. Static (electronic) scanning is employed, by individual layer and by row and column within each layer, to form a two-dimensional image of the inspection surface.