Abstract: A steering angle sensor comprising an annular drive gear, which rotates in accompaniment with rotation of a steering wheel, and further comprising a first driven gear and a second driven gear, which have magnets disposed therein and rotate in a driven manner in accordance with rotation of the annular drive gear, the steering angle sensor generating angle-of-rotation information of the steering wheel utilizing changes in magnetic fields based on rotation of the first driven gear and the second driven gear, wherein an intermediate gear that meshes with the annular drive gear, the first driven gear, and the second driven gear is interposed between the annular drive gear and the first driven gear and the second driven gear.

Abstract: There is provided a steering angle sensor in which the effect of errors in angles of rotation arising in a first driven gear and a second driven gear because of the roundness of an annular drive gear is reduced and which can generate angle-of-rotation information of a steering wheel with good precision.