The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 10, 2007
Filed:
Sep. 05, 2006
Mark B Johnson, Springfield, VA (US);
Michael M Miller, Alexandria, VA (US);
Mark B Johnson, Springfield, VA (US);
Michael M Miller, Alexandria, VA (US);
The United States of America as represented by the Secretary of the Navy, Washington, DC (US);
Abstract
Magnetic field sensors, each generating an electrical output signal in proportion to the local magnetic field, are lithographically fabricated on a semiconductor substrate with a small spatial separation. The lateral dimension of the sensors and the separation length are the order of the minimum lithographic feature size. Comparing the electrical signals to the sensors results in a measurement of the local magnetic field gradient. Large field gradients, that vary on a small spatial scale, may be associated small magnetic structures such as microscopic magnetic particles. Detection of a field gradient can be used to infer the presence of a magnetic particle.