Rotation angle detecting device

A rotation angle detecting device for detecting a rotation angle of a rotating shaft, comprising:

• a rotating part rotating integrally with the rotating shaft and including a detected portion used for detecting the rotation angle;
• a first detector arranged to oppose the detected portion and configured to detect change of a physical quantity caused by rotation of the rotating part, inside a first detection field over the detected portion and output a first detection signal representing the rotation angle of the rotating part;
• and
• a second detector arranged to oppose the detected portion and configured to detect change of the physical quantity caused by rotation of the rotating part, inside a second detection field located over the detected portion at a position different from the first detection field with respect to the rotating direction of the rotating part and output a second detection signal that is out of phase with the first detection signal but represents the rotation angle of the rotating part,
• wherein the second detection field is shorter than the first detection field with respect to a direction perpendicular to the rotating direction of the rotating part.