Shielded eddy current coils and methods for forming same on printed circuit boards
First Claim
1. An eddy current probe, comprising:
- a printed circuit board; and
a first coil component comprising a test coil formed on the printed circuit board and a second coil component comprising an active shielding coil formed on the printed circuit board, wherein the test coil and the active shielding coil are concentrically arranged and wherein the coil windings in the active shielding coil are set to limit a field induced within a test object against which the eddy current probe is placed or limit detection of eddy current fields in the test object to an area substantially coextensive with an area over which the test coil extends on the test object, wherein the test coil and the shielding coil are constituted of a single winding, and wherein a winding direction of the shielding coil is opposite to a winding direction of the test coil.
4 Assignments
0 Petitions
Accused Products
Abstract
A shielded eddy current coil probe is formed on a printed circuit board and comprises a first coil component forming a test coil and a second coil component forming an active shielding coil. The test coil and the active shielding coil are concentrically arranged and the number of coil windings in the active shielding coil and the field direction thereof are configured to limit the induced field or the sensed field in the test object to the footprint area of the test coil on the test object. Multiple sets of test coils with active shielding coils can be provided on the same or different layers of the printed circuit board to realize different driver, receiver and combined driver/receiver coil configurations.
-
Citations
19 Claims
-
1. An eddy current probe, comprising:
-
a printed circuit board; and a first coil component comprising a test coil formed on the printed circuit board and a second coil component comprising an active shielding coil formed on the printed circuit board, wherein the test coil and the active shielding coil are concentrically arranged and wherein the coil windings in the active shielding coil are set to limit a field induced within a test object against which the eddy current probe is placed or limit detection of eddy current fields in the test object to an area substantially coextensive with an area over which the test coil extends on the test object, wherein the test coil and the shielding coil are constituted of a single winding, and wherein a winding direction of the shielding coil is opposite to a winding direction of the test coil. - View Dependent Claims (2, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 17, 18, 19)
-
-
4. An eddy current probe, comprising:
-
a printed circuit board; and a first coil set and a second coil set wherein the first coil set and the second coil set located at a different layer of the printed circuit board and overlapping one another at a particular area of the printed circuit board, and wherein the first coil set and the second coil set each respectively further comprising, a respective first coil component comprising a test coil formed on the printed circuit board and a respective second coil component comprising an active shielding coil formed on the printed circuit board, wherein the test coil and the active shielding coil are concentrically arranged and wherein the coil windings in the active shielding coil are set to limit a field induced within a test object against which the eddy current probe is placed or limit detection of eddy current fields in the test object to an area substantially coextensive with an area over which the test coil extends on the test object, wherein the test coil and the shielding coil are constituted of a single winding, and wherein a winding direction of the shielding coil is opposite to a winding direction of the test coil. - View Dependent Claims (16)
-
Specification