| 摘要 |
<p>PURPOSE:To perform stable tracking control by changing the detection gain of the tracking error signal between the levels of this signal are higher and lower than the reference value based on the integration value of the tracking error signal. CONSTITUTION:The tracking error signal voltage es produced by adding a fixed level of voltage corresponding to the offset value to the difference of levels between the pilot side read signals received from right and left adjacent tracks is applied to an operational amplifier 10 together with the reference voltage -er set by a variable resistor VR1. In this case, the gain of the amplifier 10 is changed by the difference between the tracking error signal es and the reference voltage -er. Thus it is possible to correct the S-curve characteristics obtained in an offset tracking state or a tracking state where the steady deviation is secured into the satisfactory characteristics. Then the stable tracking control is carried out.</p> |
