Patent ID: 8299782

Claim:
A position sensor, comprising: a magnetic field generation portion having a pillar shape, and which generates a magnetic field, the magnetic field generation portion having a first side and a second side opposite the first side; a magnetic field detection portion for detecting a magnetic flux density of a magnetic field generated by the magnetic field generation portion, and facing the first side; and a yoke fixed to the magnetic field generation portion so as to cover at least a part of the second side along a longitudinal direction of the magnetic field generation portion, the yoke having a first end and a second end, wherein one of the magnetic field generation portion and the magnetic field detection portion is movable relative to the other in a predetermined moving direction, so as to define a range of relative movement, wherein the yoke has leg portions extending toward a plane parallel to and along the first side of the magnetic field generation portion, wherein within a part of the range of relative movement, the yoke is U-shaped in a plane that is normal to an axis parallel to and along the predetermined moving direction, and wherein a shape of the leg portions of the yoke adjacent the first end of the yoke is different from a shape of the leg portions of the yoke adjacent the second end of the yoke.