Abstract: This invention improves the accuracy of wobble signal detection for disc discrimination and reduces discrimination errors due to noise. In an optical disc apparatus, a wobble signal generator creates a wobble signal from an electrical signal which has been obtained from conversion by a pickup. A bandpass filter (BPF) is set to change its central frequency to a wobble frequency f0 and to fn different from the wobble frequency, and the filter extracts the respective frequency components from the wobble signal. An amplitude-measuring section measures amplitude levels A0 and An of the extracted multiple signals. A disc discriminator compares the multiple amplitude levels and if the amplitude A0 is greater than the amplitude An by at least a threshold level Ath, judges that a wobble is present.

Abstract: There is provided an optical disc drive comprises an optical pick-up including a laser diode (LD) and a laser diode driver (LDD) for driving the laser diode, a digital signal processor (DSP) including a write strategy circuit and low voltage differential signaling (LVDS) drivers for transmitting a produced write strategy signal, a circuit board having the DSP mounted thereon and including a line for transmitting the write strategy signal, a transmission line connecting the circuit board and the LDD and transmitting a write strategy signal, and differential resistors connected between differential lines of outputs of the LVDS drivers. Especially, a resistor having a resistance value in a range of 80 to 500? is inserted between the differential lines of outputs of the LVDS driver inside the DSP.

Abstract: In a method for compensating recording power, being suitable for an optical disk apparatus, applying the WOPC therein, as a means for compensating recording power during recording operation, and also an optical disk apparatus applying the same therein, wherein the recording operation is interrupted, when a predetermined amount of data is recorded continuously, to determine the recording power for when recoding next, from the recoding condition onto the optical disk just before interruption thereof, and thereby starting the recording, with the recording power determined from that just after said interruption thereof, wherein an adjustment is made on a tilt angle of an optical pickup when the recording power, which is determined when interrupting the recording operation, exceeds a predetermined threshold value, and the recording is started just after said interruption, with the recording power onto the optical disk just before it is interrupted.

Abstract: A write power determining method for an optical disk drive determines optimum write power information of an optical disk during the high-speed rotation of the disk. A push-pull signal amplitude is obtained at two positions in a radial direction of an optical disk before writing. A linearization value of optimum write power associated with radial positions over the whole writing area of the disk is determined on the basis of the obtained push-pull signal amplitude. The determined result is adopted as optimum write power information associated with the radial positions of the disk.

Abstract: In a focus-servo control method within an optical disc recording/reproducing apparatus, for recording or reproducing information onto/from an optical information recording medium having a track with a land and a groove, which are formed in a spiral manner on an information recording surface thereof, with moving an optical spot from the land to the groove, or from the groove to the land via an exchange portion therebetween, a focus offset value is exchanged from an offset value for the land or the groove to the offset value for the groove or the land, gradually. within a region starting from a position advancing by a predetermined time period from appearance of the exchange portion exchanging from the land to the groove or from the groove to the land, thereby providing a technology for dissolving fall down of recording/reproducing quality, due to the L/G exchange portion when recording/reproducing the information onto/from the optical disc having the land and the groove on the recording surface thereof.

Abstract: The present invention shortens a time to be elapsed from a recording interruption to a recording restart, thereby realizing a reliable recording restart. In one embodiment, an optical disk apparatus comprises an optical pickup and a processor, which includes a reproduction system circuit, a speed information detection circuit, and a position detection circuit. The reproduction system circuit is configured to generate a reproduction signal used in restarting recording of the optical disk after an interruption, based on the electrical signal from the optical pickup and setting values. The speed information detection circuit is configured to detect speed information before or after an interruption of a recording on the optical disk based on the electrical signal from the optical pickup. The position detection unit is configured to detect a recording restart position and a current position of the optical disk.

Abstract: An optical disk read/write apparatus detects a shift in the tilt during a write operation and corrects it before resuming the write operation. Specifically, when the ROPC control signal detector of the optical disk read/write apparatus controlling the write power determines that the write power has exceeded a predetermined value after a control operation, the optical disk read/write apparatus suspends the write operation through control of the laser power and controls the shift in the tilt with the tilt controller before resuming the write operation.

Abstract: A write power determining method for an optical disk drive is provided which can determine optimum write power information of an optical disk during the high-speed rotation of the disk. The write power determining method comprises the steps of: obtaining push-pull signal amplitude at two positions in a radial direction of an optical disk before writing; on the basis of the obtained push-pull signal amplitude, determining a linearization value of optimum write power associated with radial positions over the whole writing area of the disk; and adopting the determined result as optimum write power information associated with the radial positions of the disk.

Abstract: An optical disk read/write apparatus detects a shift in the tilt during a write operation and corrects it before resuming the write operation. Specifically, when the ROPC control signal detector of the optical disk read/write apparatus controlling the write power determines that the write power has exceeded a predetermined value after a control operation, the optical disk read/write apparatus suspends the write operation through control of the laser power and controls the shift in the tilt with the tilt controller before resuming the write operation.

Abstract: The present invention shortens a time to be elapsed from a recording interruption to a recording restart, thereby realizing a reliable recording restart. In one embodiment, an optical disk apparatus comprises an optical pickup and a processor, which includes a reproduction system circuit, a speed information detection circuit, and a position detection circuit. The reproduction system circuit is configured to generate a reproduction signal used in restarting recording of the optical disk after an interruption, based on the electrical signal from the optical pickup and setting values. The speed information detection circuit is configured to detect speed information before or after an interruption of a recording on the optical disk based on the electrical signal from the optical pickup. The position detection unit is configured to detect a recording restart position and a current position of the optical disk.