Patent ID: 6975108

Claim:
A high resolution transducer for non-contact electromagnetic testing, comprising: a. an insulator body; b. a ferrite core inserted in said insulator body and having a tapered end, said core characterized by a magnetic permeability and operative to provide a focused magnetic field flux; c. a high frequency (HF) coil disposed around said core operative to induce multi-frequency, multi-amplitude electromagnetic (EM) field excitations in said core, said excitations further inducing corresponding eddy currents in a tested element; and d. a direct current (DC) mechanism operative to optimize said magnetic permeability of said core, correlated with a transducer operating regime, whereby the transducer enables non-contact multi-frequency, multi-amplitude testing of single-layered and multi-layered printed circuit boards that reveals layer defects with high three-dimensional resolution.