| 摘要 |
PROBLEM TO BE SOLVED: To provide a position detection device and a magnetometric sensor output signal detection method capable of setting a reference value (threshold) to be compared with an output from a magnetometric sensor at an accurate value by an easy method. SOLUTION: A magnetic tape 8 is polarized repeatedly at a pitchλ, and the magnetometric sensor 7 can be moved relatively to the magnetic tape 8, and outputs a signal changing repeatedly corresponding to repeated polarization following movement. Comparators 32, 34 input an output signal of the magnetometric sensor 7, compare it with the reference value Ref, and output a comparison result as a pulse signal. A controller 35 counts the pulse signals from the comparators 32, 34, operates a relative moving quantity between the magnetometric sensor 7 and the magnetic tape 8, and detects the position of a lens 4 based on the operated relative moving quantity. In this case, the reference value Ref is set by acquiring an output value outputted from a non-polarized part 22a by the magnetometric sensor 7. COPYRIGHT: (C)2006,JPO&NCIPI
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