Abstract: In a method for adjusting a write strategy, data is written into the optical disc according to a first write strategy in forms of a first type of data storage structures with variable lengths and a second type of data storage structures with variable lengths. A plurality of the first type of data storage structures corresponding to a specified reference length are located, and the recording lengths thereof are operated with the specified reference length to obtain a first averaged deviation. A plurality of the second type of data storage structures formed next to the first type of data storage structures are located, and the recording lengths thereof are operated with respective reference lengths to obtain a second averaged deviation. A parameter of the first write strategy is adjusted so as to generate a second write strategy for subsequently writing data into the optical disc.

Abstract: An adaptively learning method and apparatus is used for improving a write strategy for discs of the same type produced by the same manufacturer. When a write action is completed, the previous written data is reproduced for checking the write quality of the written data. If the write quality does not comply with requirements, the write strategy will be tuned and the new write strategy will be recorded into a memory for the use of next write action. In this way, the write quality of the present write action will be better than that of the previous write action so as to maintain the write quality.

Abstract: A write strategy directory is stored in an optical recorder to provide optimum write strategies for the optical recorder to write optical discs according to characteristic values of the optical discs, respectively. The write strategy directory includes a fixed write strategy table recording therein first characteristic values of a first group of optical discs and first write strategies corresponding to the first characteristic values, respectively; and a modifiable strategy table independent from the fixed write strategy table, recording therein second characteristic values of a second group of optical discs and second write strategies corresponding to the second characteristic values, respectively.

Abstract: In a method for adjusting a write strategy, data is written into the optical disc according to a first write strategy in forms of a first type of data storage structures with variable lengths and a second type of data storage structures with variable lengths. A plurality of the first type of data storage structures corresponding to a specified reference length are located, and the recording lengths thereof are operated with the specified reference length to obtain a first averaged deviation. A plurality of the second type of data storage structures formed next to the first type of data storage structures are located, and the recording lengths thereof are operated with respective reference lengths to obtain a second averaged deviation. A parameter of the first write strategy is adjusted so as to generate a second write strategy for subsequently writing data into the optical disc.

Abstract: In a method of detecting defects during a write operation for an optical disk recording device, during a period of time immediately after writing begins, a sub-beam added (SBAD) signal is compared with a reference signal having a second threshold frequency. A defect is identified when a difference between the SBAD signal and the reference signal exceeds either a second upper limit or a second lower limit. Then, after the short period of time has elapsed, a SBAD signal is compared with and a reference signal having a first threshold frequency that is less than the second threshold frequency. A defect is identified when a difference between the SBAD signal and the reference signal exceeds either a first upper limit that is less than the second upper limit, or a first lower limit that is greater than the second lower limit.

Abstract: A down-speed recording method for a recordable optical drive with good recording quality. When the recordable optical drive is recording an optical disk and if an output power of a laser diode reaches a predetermined power, the recording speed or the rotating speed of a spindle motor is decreased in order to prevent the output power of the laser diode from exceeding the predetermined power, ensure the recording quality of the optical disk, and lengthen the lifetime of the laser diode accordingly.

Abstract: This present invention discloses a method for determining existence of a disk in an optical disk drive. Instead of using an optical pick-up head with a single laser wavelength, an optical pick-up head equipped with two different laser wavelengths is utilized to complete the determination of existence of a disk in an optical disk drive. Among the determining procedures, the formation of an S-curve containing the focus error signals is one basis for deciding the existence of a disk in the tray of the optical disk drive.

Abstract: The invention uses a thermistor to detect the ambient temperature of a pickup head. When the temperature is higher than a first predetermined temperature, the speed of the spindle motor of the optical disk drive is decreased for eliminating the heat produced from the power driver and actuator. In this way, the pickup head can be protected from burning out or suffering heat-related damage.

Abstract: A method is provided for determining whether a disk is positioned upside down inside an optical disk player. According to this method, a disk is loaded into an optical disk player, and then a laser beam is emitted that travels via a focusing device in the optical disk player to the loaded disk. Then, the focusing device is moved from a first position to a second position. While the focusing device is being moved from the first position to the second position, the variation in the intensity of the laser beam that is reflected by the disk is continuously recorded to produce a distribution curve of the intensity of the reflected laser beam. Thereafter, the method determines whether the disk is upside down based on the obtained distribution curve.

Abstract: A method of detecting a type of optical disc according to the rotation speed of a spindle motor loading the optical disc. First, the spindle motor is driven with a signal having a predetermined waveform. Next, the rotation speed of the spindle motor is detected by a Hall sensor and compared with a first predetermined rotation speed and a second predetermined rotation speed. When the detected rotation speed is faster than the first predetermined rotation speed, it is determined that there is no optical disc on the spindle motor, and it is determined that there is a mini-type optical disc on the spindle motor when the detected rotation speed is between the first predetermined rotation speed and the second predetermined rotation speed, and a normal-type optical disc is determined when the detected rotation speed is slower than the second predetermined rotation speed.

Abstract: In a method of detecting defects during a write operation for an optical disk recording device, during a period of time immediately after writing begins, a sub-beam added (SBAD) signal is compared with a reference signal having a second threshold frequency. A defect is identified when a difference between the SBAD signal and the reference signal exceeds either a second upper limit or a second lower limit. Then, after the short period of time has elapsed, a SBAD signal is compared with and a reference signal having a first threshold frequency that is less than the second threshold frequency. A defect is identified when a difference between the SBAD signal and the reference signal exceeds either a first upper limit that is less than the second upper limit, or a first lower limit that is greater than the second lower limit.

Abstract: A method of adjusting the write speed of a CD drive includes writing data from a CD drive to a disk at a first speed. Then, if the absolute time in pregroove (ATIP) error rate of the compact disk at the first speed is larger than a corresponding first preset error allowance upper limit for the first speed, then the first speed is reduced. On the other hand, if the ATIP error rate of the compact disk at the first speed is smaller than the first preset error allowance upper limit, then data continues to be written from the CD drive to the disk at the same first speed. Thus, write failures can be avoided and the quality of the written data can be improved.

Abstract: The present invention discloses a method of rapidly adjusting optical drive focus error signal level. First, select a referral focus error level. Then, sink the object lens to the bottom, and start moving the object lens in a direction of the disk.

Abstract: A track-number seeking algorithm and a seeking means for the dynamic modification of the computation of track numbers in an optical storage device employs a down counter, an up counter and a microprocessor. First, a rotation number of an optical storage disk in the microprocessor, a track error zero crossing signal of the down counter and the up counter are reset, a static track seeking number of the down counter is set, and a seeking operation is performed. The seeking operation reads the rotation number and the track error zero crossing signal, computes a residual track number, and judges whether an overflow flag is to be sent. If the overflow flag is sent, then, the rotation number is added, a pulse number of a feedback signal is reset, and the next step is to judge whether the seeking operation is outward or not. If the overflow flag is not sent, the next step is to judge directly whether the seeking operation is outward or not.