Abstract: An apparatus for light spot servo signal detection for reading an optical recording medium having a plurality of non-writable areas between writable data areas containing address information. An optical pickup provides a light spot to the non-writable areas of the optical recording medium with a predetermined state according to a control signal, and detects optical reflecting signals from the optical recording medium to generate a detection signal. A signal adjusting module offsets signal levels of the detection signal to an operating range to generate an offset shifted detection signal. An analog to digital converter digitizes the offset shifted detection signal to generate a digital signal. A detection circuit detects the servo detection signal according to the digital signal.

Abstract: A laser power control system and related method for reducing a settling time in a target laser power transition are disclosed. The laser power control system includes a state decision circuit, for generating a state decision signal according to a selected operational state of a target circuit; a plurality of buffers, for storing a plurality of control data corresponding to a plurality of candidate operational states of the target circuit respectively; and a multiplexer, coupled between the state decision circuit and the buffers, for coupling a selected buffer of the buffers and the target circuit according to the state decision signal for outputting a control datum stored in the selected buffer to the target circuit.

Abstract: A signal processing apparatus includes sample and hold units for holding a plurality of analog photo diode signals. A signal holding controller generates control signals to the sample and hold units for holding the analog photo diode signals. Analog adjusting modules adjust the held analog photo diode signals. A multiplexer selectively couples one input end of the multiplexer to the output end of the multiplexer for outputting the adjusted analog photo diode signals. An analog to digital converter converts the adjusted analog photo diode signals into digital photo diode signals.

Abstract: A method for controlling a specific output power level emitted from a laser diode (LD) in an optical pick-up head unit (OPU) is disclosed. The LD is configured to provide a plurality of output power levels for accessing/recording an optical disc. The method includes: determining a specific power control value according to a first output power level, a second output power level, a first power control value of the first output power level, and the specific output power level, wherein the first output power level is less than the specific output power level and greater than the second output power level; and driving the LD to emit the specific output power level according to the specific power control value, the first power control value, and a second power control value of the second output power level.

Abstract: The invention provides a wobble detection circuit. An exemplary embodiment of the wobble detection circuit comprises an automatic gain control module, an analog to digital converter, a digital band pass filter, and a digital band pass filter. The automatic gain control module amplifies a first input signal and a second input signal detected by a pickup head to the same magnitude to obtain a first amplified signal and a second amplified signal. The adder then subtracts the second amplified signal from the first amplified signal to obtain an analog wobble signal. The analog to digital converter then converts the analog wobble signal to a first digital wobble signal. Finally, the digital band pass filter accepts frequency components of the first digital wobble signal within a pass band and rejects frequency components of the first digital wobble signal outside the pass band to obtain a second digital wobble signal.

Abstract: The present invention discloses a servo system of an optical storage device, the optical storage device includes a pick-up unit for detecting signals reflected from an optical disc to generate a plurality of detecting signals, the servo system includes: a focus error signal generating module coupled to the pick-up unit for generating a plurality of focus error signals according to the detecting signals; a focus servo control module coupled to the focus error signal generating module for generating a focus control signal according to the focus error signals; and a focus actuator coupled to the focus servo control module and the pick-up unit for controlling the pick-up unit to adjust a focus position on the optical disc according to the focus control signal.

Abstract: The invention relates to a track-jump control device, and in particular, to a track-jump control device for determining track-jump timing in an optical disc drive. A track-jump control device of a PUH comprises an L/G position indicator, a header alignment controller, and a jump controller. The L/G position indicator calculates an amount of sectors between the current position and an upcoming L/G switch point to generate a distance value. The header alignment controller controls the destination position locating in a safe area between two headers, and then generating a jump enabling signal. The jump controller coupled to the L/G position indicator and the header alignment controller determines track-jump timing according to the distance value and the jump enabling signal.

Abstract: A recording method for an optical disk drive is implemented as follows. First, at least one of the level of the focusing error signal, the level of the tracking error signal, a wobble synchronization pattern loss, the error rate of demodulating a wobble signal, the frequency of buffer under-run occurrence, the temperature of the drive, the wobble jitter and the level of write power is detected. If at least one detected value exceeds the preset value, the recording will be ceased. Then, the rotation speed of the optical disk drive is decreased, and the recording is resumed with the decreased rotation speed. If at least one of the temperature of the drive, the wobble jitter and the estimated write power exceeds the reset value before recording starts, the rotation speed of the optical disk drive is decreased before recording.

Abstract: A method for calibrating an initial driving signal for driving an optical pick-up head of an optical disk drive is provided. On one embodiment, said optical disk drive is utilized for reading or writing data on an optical disk, the optical disk comprises a plurality of auto power control areas (APC areas) and a plurality of data areas, and the APC areas and the data areas are interleaved in between. First, in the APC areas, an initial driving signal is used to drive the optical pick-up head to emit laserbeam. A detected level of the laserbeam is then obtained. An update initial driving signal is then calibrated according to the detected level and a target level.

Abstract: A method for controlling a position of a laser spot of a laser beam on an optical storage medium of a land and groove recording/reproduction type is provided. The method includes: detecting a pulse occurring in a reference signal while the laser spot is passing through a boundary between a groove track and a land track, wherein the reference signal is generated according to a reflected laser beam from the optical storage medium; determining a compensation value of the reference signal according to the pulse; utilizing the compensation value to adjust the reference signal for generating an adjusted reference signal; and utilizing the adjusted reference signal to control the position of the laser spot.

Abstract: A track-jump control system and method are provided. The track-jump control system applied in an optical disc drive comprises a signal generator, a protection device, a velocity estimator, and a controller. The signal generator receives the signal from the PUH and generates a tracking signal and a position signal. The protection device receives the position signal and when the position signal represents the PUH pass a predetermined position of the optical disc, the protection device generates a protection signal. The velocity estimator estimates the velocity of the PUH according to the tracking signal, and then generates a velocity signal. The controller receives the velocity signal and the protection signal, protects the velocity signal according to the protection signal, and generates a control signal to control the track-jump according to the protected velocity signal.

Abstract: An automatic power control system, a down sampling circuit and a down sampling method. The automatic power control system is incorporated in an optical disc drive comprising a laser diode for receiving a control signal to generate a laser beam; and a photodetector for detecting the laser beam to generate an analog input signal. The automatic power control system comprises an analog-to-digital converter, a down sampling circuit, a comparator, and a digital-to-analog converter. The analog-to-digital converter converts the analog input signal to digital data. The down sampling circuit, coupled to the analog-to-digital converter, comprises a down sampler, a counter, and a controller. The down sampler receives a predetermined amount of digital data to generate representation data. The counter, coupled to the down sampler, calculates the amount of digital data, and resets the down sampler when the amount equals or exceeds the predetermined count.

Abstract: An automatic power control system, a down sampling circuit and a down sampling method. The automatic power control system is incorporated in an optical disc drive comprising a laser diode for receiving a control signal to generate a laser beam; and a photodetector for detecting the laser beam to generate an analog input signal. The automatic power control system comprises an analog-to-digital converter, a down sampling circuit, a comparator, and a digital-to-analog converter. The analog-to-digital converter converts the analog input signal to digital data. The down sampling circuit, coupled to the analog-to-digital converter, comprises a down sampler, a counter, and a controller. The down sampler receives a predetermined amount of digital data to generate representation data. The counter, coupled to the down sampler, calculates the amount of digital data, and resets the down sampler when the amount equals or exceeds the predetermined count.

Abstract: A recording method for an optical disk drive is implemented as follows. First, at least one of the level of the focusing error signal, the level of the tracking error signal, a wobble synchronization pattern loss, the error rate of demodulating a wobble signal, the frequency of buffer under-run occurrence, the temperature of the drive, the wobble jitter and the level of write power is detected. If at least one detected value exceeds the preset value, the recording will be ceased. Then, the rotation speed of the optical disk drive is decreased, and the recording is resumed with the decreased rotation speed. If at least one of the temperature of the drive, the wobble jitter and the estimated write power exceeds the reset value before recording starts, the rotation speed of the optical disk drive is decreased before recording.

Abstract: A recording method for an optical disk drive is implemented as follows. First, at least one of the level of the focusing error signal, the level of the tracking error signal, a wobble synchronization pattern loss, the error rate of demodulating a wobble signal, the frequency of buffer under-run occurrence, the temperature of the drive, the wobble jitter and the level of write power is detected. If at least one detected value exceeds the preset value, the recording will be ceased. Then, the rotation speed of the optical disk drive is decreased, and the recording is resumed with the decreased rotation speed. If at least one of the temperature of the drive, the wobble jitter and the estimated write power exceeds the reset value before recording starts, the rotation speed of the optical disk drive is decreased before recording.

Abstract: The present invention sets forth a power saving method and a power saving system applied in an optical disk drive. The power saving system comprises a central processing unit, a spindle motor, an optical pick-up unit, an analog portion of control circuits and a digital portion of control circuits. Each of the analog or digital portions of control circuits can be divided into several sets of circuits. Each set of circuits is coupled to an associated operation mode of the optical disk drive. The power saving system further comprises a power controlling unit for differentiating the specific sets of circuits not being used in the specific operation mode and powering them down. The sets of circuits not being used will be powered up while the associated operation mode in which they are required to operate is nearly started. The present invention also provides a power saving method of powering down the sets of circuits not being used relative to a specific operation mode of the optical disk drive.

Abstract: An apparatus and a method for compensating periodic signal in an optical disc drive are described. The control apparatus includes an amplitude processing unit, a phase processing unit, and a wave generator. The amplitude processing unit processes the amplitude of the input signal (Sin) based on a reference signal (Sref) for generating an amplitude signal (Sad) wherein the amplitude signal (Sad) has at least one amplitude value (Vad). The phase processing unit processes the phase of the input signal (Sin) based on the reference signal (Sref) for generating a phase signal (Spd) wherein the phase signal (Spd) has at least one phase value (Vpd) during the cycle of the reference signal (Sref). The wave generator generates a compensated wave signal (Scom) based on the amplitude value (Vad) and the phase value (Vpd) during the cycle of the reference signal (Sref), and the wave generator outputs the compensated wave signal (Scom) for compensating the periodic signal of the input signal (Sin).

Abstract: A recording method for an optical disk drive is implemented as follows. First, at least one of the level of the focusing error signal, the level of the tracking error signal, a wobble synchronization pattern loss, the error rate of demodulating a wobble signal, the frequency of buffer under-run occurrence, the temperature of the drive, the wobble jitter and the level of write power is detected. If at least one detected value exceeds the preset value, the recording will be ceased. Then, the rotation speed of the optical disk drive is decreased, and the recording is resumed with the decreased rotation speed. If at least one of the temperature of the drive, the wobble jitter and the estimated write power exceeds the reset value before recording starts, the rotation speed of the optical disk drive is decreased before recording.

Abstract: A high pass filtering device for an optical disc drive comprises a first low pass filter (LPF) of a first sampling rate, filtering a digital input signal; a down-sampler receiving a first filtered signal form the first LPF to down-sample the first filtered signal by an integer factor N; a second LPF of a second sampling rate, filtering a first down-sampled signal from the down-sampler, wherein the second LPF has a corner frequency corresponding to a desired frequency of the high pass filtering device, and the second sampling rate is equal to 1/N times the first sampling rate; an up-sampler receiving a second filtered signal from the second LPF to up-sample the second filtered signal by the factor N; and a subtractor subtracting an up-sampled signal output by the up-sampler from the digital input signal when the filter frequency is below a threshold frequency.

Abstract: A method for controlling a specific output power level emitted from a laser diode (LD) in an optical pick-up head unit (OPU) is disclosed. The LD is configured to provide a plurality of output power levels for accessing/recording an optical disc. The method includes: determining a specific power control value according to a first output power level, a second output power level, a first power control value of the first output power level, and the specific output power level, wherein the first output power level is less than the specific output power level and greater than the second output power level; and driving the LD to emit the specific output power level according to the specific power control value, the first power control value, and a second power control value of the second output power level.