Abstract: A method and apparatus for writing data to an optical storage medium are disclosed. A write signal indicating power levels of a laser diode is generated by encoding and decoding codewords. The codewords are generated and decoded according to a specific requirement proposed by the present invention. By doing so, toggling (i.e. state changing) times occurring in channels transferring the codewords can be significantly reduced to avoid the problems of pulse distortion and disappearance in high frequency transmission. Alternatively, toggles appearing in the respective channels can be spread to avoid interference between the channels. Further, a phase adjustment device for adjusting a phase of each codeword is disclosed.

Abstract: A method and an apparatus for deciding a spherical aberration compensation (SAC) value for an optical storage medium are provided. The optical storage medium comprises at least one recording layer and a cover layer. The SAC value is suitable for a selected one of the at least one recording layer. First, a focus search on the optical storage medium is performed to derive a focus error (FE) signal in response to a testing SAC value. Then, a center level and a center basis corresponding to the testing SAC value according to the FE signal is determined. The SAC value according to the center level, the center basis, and the testing SAC value is also determined. When the center level and the center basis are equal, the SAC value is determined to be the testing SAC value.

Abstract: A method and apparatus for writing data to an optical storage medium are disclosed. A write signal indicating power levels of a laser diode is generated by encoding and decoding codewords. The codewords are generated and decoded according to a Successive State Change Criterion (SSCC) or SSCC II proposed by the present invention. By doing so, toggling (i.e. state changing) times occurring in channels transferring the codewords can be significantly reduced to avoid the problems of pulse distortion and disappearance in high frequency transmission. Alternatively, toggles appearing in the respective channels can be spread to avoid interference between the channels. Further, a phase adjustment device for adjusting a phase of each codeword is disclosed.

Abstract: A recording apparatus for optical data includes a photo detection IC for producing a plurality of phase signals; a plurality of sample/hold (S/H) circuits electrically connected to the photo detection IC; a plurality of limiter circuits electrically connected to the photo detection IC; a channel signal generator connected to the S/H circuits; and a level shift circuit connected to an output of the channel signal generator. The recording apparatus for optical data prevents the interference of servo signal during high speed operation and ensures normal operation of S/H circuits thereof.

Abstract: The invention provides a servo calibration mark detection circuit for use in an optical disk drive. In one embodiment, the servo calibration mark detection circuit comprises a summing processor, a slicing level generator, and a comparator. The summing processor sums an intensity of a light beam reflected from both an inner groove and an outer groove to obtain a first signal. The slicing level generator generates a slicing level. The comparator then compares the first signal with the slicing level to obtain a second signal, wherein the second signal indicates a first location of a first servo calibration mark recorded on the inner groove and a second location of a second servo calibration mark recorded on the outer groove.

Abstract: A method and an apparatus for deciding a spherical aberration compensation (SAC) value for an optical storage medium are provided. The optical storage medium comprises at least one recording layer and a cover layer. The SAC value is suitable for a selected one of the at least one recording layer. First, a focus search on the optical storage medium is performed to derive a focus error (FE) signal in response to a testing SAC value. Then, a center level and a center basis corresponding to the testing SAC value according to the FE signal is determined. The SAC value according to the center level, the center basis, and the testing SAC value is also determined. When the center level and the center basis are equal, the SAC value is determined to be the testing SAC value.

Abstract: An optical data accessing apparatus and method for changing the access from a first data layer to a second data layer of an optical storage medium are provided. The first data layer corresponds to a first SAC value, while the second data layer corresponds to a second SAC value. A processor of the optical data accessing apparatus is adapted for: (1) generating and sending a focus off signal to a pickup control unit to disable focus control; (2) generating a target value for an SAC to adjust an SAC value from the first SAC value to the target value, wherein the target value is between the first SAC value and the second SAC value; and (3) generating and sending a focus activation signal to the pickup control unit to re-enable the focus control to focus on the second data layer while the SAC value reaches the target value.

Abstract: An optical disc drive includes a servo system and a system behavior detection module. The system behavior detection module includes a controller and a signal feeding unit coupled to the controller and the servo system. The controller is operable in a detection mode and in a normal operation mode. In the detection mode, the controller enables the signal feeding unit so as to introduce an exciting signal into the servo system. In the normal operation mode, the controller disables the signal feeding unit so as to inhibit introduction of the exciting signal into the servo system.

Abstract: The invention provides a servo calibration mark detection circuit for use in an optical disk drive. In one embodiment, the servo calibration mark detection circuit comprises a summing processor, a slicing level generator, and a comparator. The summing processor sums an intensity of a light beam reflected from both an inner groove and an outer groove to obtain a first signal. The slicing level generator generates a slicing level. The comparator then compares the first signal with the slicing level to obtain a second signal, wherein the second signal indicates a first location of a first servo calibration mark recorded on the inner groove and a second location of a second servo calibration mark recorded on the outer groove.

Abstract: A recording apparatus for optical data includes a photo detection IC for producing a plurality of phase signals; a plurality of sample/hold (S/H) circuits electrically connected to the photo detection IC; a plurality of limiter circuits electrically connected to the photo detection IC; a channel signal generator connected to the S/H circuits; and a level shift circuit connected to an output of the channel signal generator. The recording apparatus for optical data prevents the interference of servo signal during high speed operation and ensures normal operation of S/H circuits thereof.

Abstract: A phase locked loop capable of compensating for errors caused by cycle slips. The phase locked loop includes a phase detection unit for generating a phase error signal; a loop filter for filtering the phase error signal and generating a first control signal; a cycle slip detector for detecting whether a cycle slip has occurred according to the phase error signal and generating a slip indication signal; a toggling unit for toggling the selection between a first value and a second value as a compensation signal according to the slip indication signal; an accumulator for accumulating the compensation signal and generating a second control signal; an adder for adding the first control signal and the second control signal and generating a third control signal; and a controllable oscillator for generating the output clock at a frequency based on the third control signal.

Abstract: A phase locked loop capable of compensating for errors caused by cycle slips. The phase locked loop includes a phase detection unit for generating a phase error signal; a loop filter for filtering the phase error signal and generating a first control signal; a cycle slip detector for detecting whether a cycle slip has occurred according to the phase error signal and generating a slip indication signal; a toggling unit for toggling the selection between a first value and a second value as a compensation signal according to the slip indication signal; an accumulator for accumulating the compensation signal and generating a second control signal; an adder for adding the first control signal and the second control signal and generating a third control signal; and a controllable oscillator for generating the output clock at a frequency based on the third control signal.

Abstract: A method for controlling an optical drive to record data onto a disc. The optical recorder has a pick up head for emitting laser onto the disc to record data onto the disc. The method includes adjusting a write power and a write strategy of the optical drive according to a linear velocity of the disc when passing by the pick up head.

Abstract: A wobbling signal reproduction device has a first low-pass filter, a second low-pass filter, a first auto gain control circuit, a second auto gain control circuit, a subtraction circuit unit and a band-pass filter. The band-pass filter is connected to an output terminal of the subtraction circuit unit to eliminate noise of reflected light beams due to a recording signal during the recording process. Thus, a satisfactory wobbling signal is available.

Abstract: The present invention provides a method and a related device for determining a slicing level of a track-crossing signal. The method includes reading a Track Error Zero Crossing (TEZC) signal of an optical storage device, reading the track-crossing signal such as a Radio Frequency Ripple (RFRP) signal of the optical storage device, sampling a peak level and a bottom level from the track-crossing signal according to the track-crossing signal and the TEZC signal, and determining a level between the peak level and the bottom level as the slicing level.

Abstract: An optical disc drive includes a servo system and a system behavior detection module. The system behavior detection module includes a controller and a signal feeding unit coupled to the controller and the servo system. The controller is operable in a detection mode and in a normal operation mode. In the detection mode, the controller enables the signal feeding unit so as to introduce an exciting signal into the servo system. In the normal operation mode, the controller disables the signal feeding unit so as to inhibit introduction of the exciting signal into the servo system.

Abstract: A method for controlling an optical drive to record data onto a disc. The optical recorder has a pick up head for emitting laser onto the disc to record data onto the disc. The method includes adjusting a write power and a write strategy of the optical drive according to a linear velocity of the disc when passing by the pick up head.