| 摘要 |
PURPOSE:To detect every defective minor loop in a short time, by varying a bias magnetic field repeatedly and gently between the upper limit value and the lower limit value of the operating range. CONSTITUTION:The bias magnetic field is set to an upper limit value HU during the period from a time t1 to a time t2 and is set to a lower limit value HL during the period from a time t3 to a time t4 and is set continuously to values between the upper limit value HU and the lower limit value HL during the period from the time t2 to the time t3 and the period from the time t4 to a time t5. By this applying method of the bias magnetic field, the bias magnetic field is set to the upper limit value HU and the lower limit value HL of a required operating range in one test, and the bias magnetic field changing continuously to values between them is applied, and thus, every defective minor loop is detected in a short time. |
