Patent ID: 8340781

Claim:
A sensor element configured to be insertable into a human body, comprising: a cylinder having an outer surface, two ends, a longitudinal axis, an inner space with a diameter, an opening at at least one end of the cylinder, a slit of a predetermined width formed along the longitudinal axis of the cylinder, wherein the width of said slit is less than the diameter of an inner space of the cylinder; a coil element group having at least two coil elements, each of the coil elements is an electrical coil having a wound wire portion with two lead portions respectively formed at both ends of each of the coil elements, said wound wire portion is formed on the outer surface of said cylinder, and said two lead portions of each of the coil elements are led into said inner space of said cylinder by passing through said slit, and at least two pairs of electrically conductive wire set in said inner space, and each of the at least two pairs of electrically conductive wire is electrically connected to each of said two lead portions and is externally led out from said opening at one end of said cylinder.