| 摘要 |
<P>PROBLEM TO BE SOLVED: To propose a magnetic pattern detection apparatus in which reduction in detection accuracy of a magnetic pattern can be avoided even if an output level of a sensor output signal of a magnetic sensor device varies due to an individual difference or a temperature. <P>SOLUTION: A magnetic pattern detection apparatus 1 includes a first offset adjusting circuit 831 which produces a correction output signal by adding an addition signal to a rectification signal from a magnetic sensor device 20, a magnetic pattern detection section 100 which detects a magnetic pattern of a medium 2 on the basis of the correction output signal which is produced when the medium 2 passes through the magnetic sensor device 20, and an addition signal adjusting section 97 which performs offset adjustment processing for turning an output level of the correction output signal to a target output level by adjusting an output level of the addition signal each time the magnetic pattern of the medium 2 is detected. Variation in an output level of a sensor output signal caused by an individual difference or heating of a magnetic sensor element 40 is corrected by the offset adjustment processing, thereby avoiding or suppressing reduction in detection accuracy of the magnetic pattern. <P>COPYRIGHT: (C)2012,JPO&INPIT |
