Application Number | 00128872 | Application Date | 2000.09.22 |
Publication Number | 1289116 | Publication Date | 2001.03.28 |
Priority Information | 1999/9/22 JP 268184/99 | ||
International Classification |
G11B7/09;G11B21/10 | ||
Applicant(s) Name | Nippon Pioneer Co. | ||
Address | |||
Inventor(s) Name | Tanagisawa Takuma;Kurihayashi Sukemoto | ||
Patent Agency Code | 72001 | Patent Agent | wang yue |
AbstractA disc has a physical factor changing a shape or a reflection coefficient in a tangential direction of a record track. A tracking control apparatus for the disc is provided with: a detecting device, a second detector, a third detector and a fourth detector; a first amplifying device, a second amplifying device; a first adding device for calculating a first sum signal; a second adding device for calculating a second sum signal; and a first subtracting device for calculating a difference between the first an second sum signals and outputting the difference as a tracking error signal. The tracking control apparatus is also provided with an amplitude comparing device for determining the first gain and the second gain on the basis of differences between the output signals. |