Track jump method for a recording medium
View Patent ↗A track jump method for an optical recording/reproducing medium is provided. In the track jump method, once a track jump command is input, a track jump operation is held until a falling edge of a header mask signal is detected. The track jump starts at the falling edge of the header mask signal and ends before a rising edge of the header mask signal so that a TZC signal is not influenced by a header during the track jump. Therefore, the track jump can be exactly and stably performed. In particular, when the track jump command is input, a PLL of a wobble signal is inhibited, and a PLL-wobble signal is held to a previous value obtained before the track jump is performed, during the track jump, or a header mask signal is generated using a read channel signal which is not influenced by a wobble period, until a wobble signal becomes stable after a track jump. During a normal servo, a header mask signal is generated using a PLL-wobble signal to mask a header area. Therefore, a header area coming first after the track jump is completed can be stably masked, thereby preventing a system from being unstable due to a header during the track jump.
1. A track jump method performed on a disc on which a plurality of header areas having different phases are disposed between recordable data areas, in which information for recognition of reference frequency is provided in wobbling shape on a track, to separate the data areas, the track jump method comprising the steps of:
receiving a track jump command;
checking whether a current location of a pickup head is the end of a header area when the track jump command is received;
standing by without performing a track jump when the current location of the pickup head is not the end of the header area, and performing the track jump with inhibition of a phase locked loop (PLL) of a wobble signal and with a generation of a previously generated PLLed-wobble signal when the current location of the pickup head is the end of the header area; and
resuming the PLL of the wobble signal when the track jump is completed.
2. The track jump method of claim 1 , wherein the checking step determines an off-point of a header mask signal indicating a header area as the end point of header area.
3. The track jump method of claim 1 , wherein the PLL inhibiting step inhibits the PLL of the wobble signal and continuously generates the previously generated PLLed-wobble signal obtained before the track jump is performed.
4. The track jump method of claim 1 , wherein the PLL inhibition step slices a sum of optical reflected signals from the optical recording medium at certain level to generate a header mask signal indicating a header area.
5. The track jump method of claim 1 , wherein the PLL inhibiting step slices a difference between optical reflected signals, which area divided in a track direction from the optical recording medium, at a certain level to generate a header mask signal indicating a header area.
6. The track jump method of claim 1 , wherein the PLL inhibiting step counts wobble signals subjected to the PLL to generate a header mask signal indicating a header area.
7. The track jump method of claim 1 , wherein the PLL resuming step counts wobble signals subjected to the PLL to generate a header mask signal indicating a header area when the track jump is completed.
8. The track jump method of claim 1 , wherein the PLL inhibiting step inhibits the PLL of the wobble signal in a section in which a header mask signal is on.
9. The track jump method of claim 1 , wherein the PLL resuming step terminates the track jump before a point at which a header mask signal indicating a header area is turned on.
10. A track jump method performed on a disc on which a plurality of header areas having different phases are disposed between recordable data areas to separate the data areas, the track jump method comprising the steps of:
receiving a track jump command;
checking whether a current location of a pickup head is a header area when the track jump command is received; and
performing the track jump when the header area ends as a result of the checking step while inhibiting a phase locked loop (PLL) of a wobble signal and while generating a previously generated PLLed-wobble signal and standing by without performing a track jump until the header area ends if the current location of the pickup head is the header area as a result of the checking step.
11. The track jump method of claim 10 , wherein the checking step determines a falling point of a header mask signal indicating an end point of the header area.
12. The track jump method of claim 10 , wherein the track jump performing step ends before a rising point of a header mask signal indicating a header area.
13. The track jump method of claim 10 , wherein when an N-time consecutive track jump command is received, a procedure of starting the track jump at a falling edge of a header mask signal, ending the track jump before a rising edge of the header mask signal, and turning on a servo is repeated N times.
14. A track jump method performed on a disc on which a plurality of header areas having different phases are disposed between recordable data areas, in which information for recognition of reference frequency is provided in wobbling shape on a track, to separate the data areas, the track jump method comprising the steps of:
performing a track jump while generating a previously generated PLLed-wobble signal and inhibiting a phase locked loop (PLL) of a wobble signal when a track jump command is received, wherein the track jump is started at a point where a header areas ends; and
resuming the PLL of the wobble signal when the track jump is completed.
15. The track jump method of claim 14 , wherein the PLL inhibiting step inhibits the PLL of the wobble signal and continuously generates the previously generated PLLed-wobble signal obtained before the track jump is performed, during the track jump.
16. The track jump method of claim 14 , wherein the PLL inhibiting step starts the track jump at a point where a header area ends when the track jump command is input.
17. The track jump method of claim 14 , wherein the PLL inhibiting step inhibits the PLL of the wobble signal in a section in which a header mask signal is on.
18. A track jump method for an optical recording medium on which a plurality of header areas having different phases are disposed between data areas, the method comprising the steps of:
(a) checking whether a current location of a pickup head is the end of a header area when a track jump command is received; and
(b) starting the track jump when the current location of the pickup head is the end of the header while a phase locked loop (PLL) of a wobble signal is inhibited and while generating a previously generated PLLed-wobble signal.
19. The method of claim 18 , wherein the step (a) determines an off-point of a header mask signal indicating a header area as the end point of the header area.
20. The method of claim 18 , further comprising:
(c) resuming a PLL of the wobble signal when the track jump is completed.
21. The method of claim 20 , wherein the step (c) maintains the track jump until a point at which a header mask signal indicating a header area is turned on.
22. The method of claim 18 , wherein the step (b) inhibits the PLL of the wobble signal and continuously generates the previously generated PLLed-wobble signal obtained before starting of the track jump.
23. The method of claim 18 , wherein the step (b) counts wobble signals subjected to the PLL to generate a header mask signal indicating a header area.
24. The method of claim 18 , wherein the step (b) inhibits the PLL of the wobble signal in a section in which a header mask signal is on.
25. A track jump method for an optical recording medium on which a plurality of header areas having different phases are disposed between data areas, the method comprising the steps of:
(a) checking whether a current location of a pickup head is a header area when a track jump command is received; and
(b) determining whether to start the track jump based on the checking step (a), wherein the track jump is started when the header area ends, and a phase locked loop (PLL) of a wobble signal is inhibited and a previously generated PLLed-wobble signal is generated during the track jump.
26. The method of claim 25 , wherein the track jump is started when the current location is the end of the header as a result of the step (a).
27. The method of claim 25 , wherein the step (a) determines an off-point of a header mask signal indicating a header area as the end point of the header area.
28. The method of claim 25 , further comprising:
(c) resuming a PLL of the wobble signal when the track jump is completed.
29. A device for controlling a track jump for an optical recording medium, the device comprising:
a pickup head;
a controller to check whether a current location of the pickup head is a header area on the optical recording medium when a track jump command is received and to determine whether to start the track jump based on the checking result; and
a phase locked loop (PLL) unit to continuously generate and output a previously generated PLLed-wobble signal during the track jump being started when the header area ends.
30. The device of claim 29 , wherein the controller inhibits the PLL unit from performing a PLL operation during the track jump.