| 摘要 |
A controller (30) is capable of operating in two possible operative modes, each mode having a corresponding characteristic (11; 12). Said characteristics have an overlap in a range of error signal values [TLL-TN]. The controller is capable of switching from one mode to another, based on the value of the time-derivative (() of the input error signal (e), so that, for a certain input error signal within said range [TLL-TN], the controller can be in any of its modes. This controller can be used for focus or tracking control purposes in an optical disk drive. |
