| 摘要 |
<p>[PROBLEMS] To provide a position sensing device employing a magnetoresistive element arranged to perform position sensing accurately using a magnet and a sensor moving while opposing the magnet. [MEANS FOR SOLVING PROBLEMS] Circular surface (2a) of a magnet (2) is magnetized to N pole and the back (2b) is magnetized to S pole. A sensor (10) moves in the X-Y plane at a position separated from the surface (2a) of the magnet (2). A pair of X direction sensing elements (20X1, 20X2) and a pair of Y direction sensing elements (20Y1, 20Y2) are provided in the sensor (10). In the X direction sensing elements (20X1, 20X2), directions (B) of a bias magnetic field applied to a free magnetic layer are reversed, and, when the sensor moves in the Y direction, a fall in sensitivity of one of the X direction sensing elements (20X1, 20X2) is compensated for by enhancing sensitivity of the other. This is also true with the Y direction sensing elements (20Y1, 20Y2). Consequently, position sensing outputs in the X direction and the Y direction can be obtained accurately from the sensor (10).</p> |
