Abstract: An optical disk playback device includes a control means (an LSI 5 for system control) for performing a track search according to contents information, comparing a current track start point position at the time after performing the track search with a target track start point position, when the comparison result shows that they differ from each other, setting up a new target track start point position by performing a predetermined arithmetic operation, then performing a track search again, and, when a new current track start point position at the time after performing the track search again matches the set-up new target track start point position, starting a playback from the new current track start point position.
Abstract: A recording medium for a disk drive has a plurality of tracks defined by servo wedges that are written using a first servo spiral set, a second servo spiral set, and a correction factor that accounts for the differences in the first set of spirals and the second set of spirals. The differences may be differences in position values decoded from the first set of spirals and position values decoded from the second set of spirals or differences in timing values decoded from the first set of spirals and timing values decoded from the second set of spirals. The first servo spiral set is used in writing components of the servo wedges that define a first set of tracks. The second servo spiral set and the correction factor are used in writing components of the servo wedges that define a second set of tracks.
Abstract: A data recording/reproducing system (1) reads a recording signal written on a recording track of a recording medium (3), by using light, which is modulated by a drive signal wherein a frequency signal is superposed for scanning the signal along the recording track at a prescribed scanning speed. Then, the system reproduces the read signal as data. The data recording/reproducing system is provided with a computer (13) for controlling the superposition frequency of the frequency signal for the drive signal corresponding to the scanning speed, and an LD driver (17).
Abstract: A method for controlling layer jump in an optical disc drive is provided. In one embodiment of the present invention, upon request of layer jump, a circumferential position of a rotating disc can be compared with predetermined circumferential position stored in a memory based on a signal generated at a spindle motor and layer jump operation can be performed at the predetermined circumferential position. The predetermined circumferential position can correspond to a position where displacement of a disc in up and down direction while the disc makes one rotation becomes largest and/or smallest. The predetermined circumferential position can be detected when an optical disc inserted is recognized to have two or more recording layers based on a driving signal applied to a focusing actuator at an outer circumference of the disc while a focusing servo is turned on.
Abstract: A backup device and a one-key data backup method for the same use a backup device having ability to retrieve a memory card and an optical disc. The backup device is connected to an external computer. A backup application is installed having backup conditions configured in the external computer. When an input unit of the backup device is triggered, the backup device sends a backup request instruction to the external computer. The external computer executes the backup application upon receiving the backup request instruction, and records data of the memory card to an optical disc, or saves the data of the optical disc in the memory card based on configured backup conditions.
Abstract: A recording/reproducing device includes: a data comparing section which compares, at the time of ejection of an optical disc, recorded information recorded on a ROM layer of the optical disc and relevant information (e.g., additional data) which is stored in the recording/reproducing device and which is related to registered information (e.g., content) recorded on an RE layer of the optical disc; and a data selecting section which selects, based on a result of the comparison by the data comparing section, relevant information for recording to be recorded on the ROM layer of the optical disc from among the relevant information.
Abstract: A tracking signal generating apparatus is provided with: a reading device for reading reflected light of a laser beam applied onto a recording medium, thereby obtaining a resulting read signal; an amplitude-limiting device for limiting an amplitude level of the read signal by a predetermined amplitude value, thereby obtaining an amplitude limit signal; a filtering device for performing a high-frequency emphasis filtering process on the amplitude limit signal, thereby obtaining an equalization-corrected signal; and a generating device for performing a phase comparison process on the equalization-corrected signal, thereby generating the tracking signal.
Abstract: An extreme ultraviolet light system includes a drive laser system that produces an amplified light beam; a target material delivery system configured to produce a target material at a target location; a beam delivery system configured to receive the amplified light beam emitted from the drive laser system and to direct the amplified light beam toward the target location; and a metrology system. The beam delivery system includes converging lens configured and arranged to focus the amplified light beam at the target location. The metrology system includes a light collection system configured to collect a portion of the amplified light beam reflected from the converging lens and a portion of a guide laser beam reflected from the converging lens. The light collection system includes a dichroic optical device configured to optically separate the portions.
Type:
Application
Filed:
December 15, 2009
Publication date:
June 16, 2011
Applicant:
CYMER INC.
Inventors:
Vahan Senekerimyan, Nam-Hyong Kim, Robert A. Bergstedt, Igor V. Fomenkov, William N. Partlo
Abstract: An optical media disk is treated with a light-sensitive material that impedes the ability of an optical media player from reading data stored on the disk. This light-sensitive material is a material that changes phase upon exposure to one or more wavelengths of light. During the initial phase, the light-sensitive material will render the disk unreadable. After activation, however, the disk becomes permanently readable by conventional optical media players. In this fashion, theft of yet-to-be-activated optical media is deterred.
Type:
Application
Filed:
February 7, 2011
Publication date:
June 9, 2011
Applicants:
Sony Corporation, Sony Pictures Entertainment Inc.
Abstract: A filter, including a direct-current (DC) tracking unit, a subtracter and a control unit, is provided. The DC tracking unit extracts a DC component of a radio-frequency (RF) signal and accordingly generates a level signal. The subtracter subtracts the level signal from the RF signal to generate a RF coupling signal. The control unit determines whether to transmit a setting signal to the DC tracking unit according to the level variation of the RF coupling signal, so as to adjust a characteristic parameter of the DC tracking unit.
Abstract: An optical information media, system, and method for providing ubiquitous reading and selective writing is disclosed. By placing data structures representing a nonstandard book type in byte “0” of the media, the media is made universally bootable and universally readable in substantially any DVD drive. On the other hand, data structure representing a version code or disc category is placed in byte “0” or another byte of the control data zone in order to identify the media and enable writing in select drives. The version code and/or disc category identifies the media and calls for one or more write strategies configured for writing to the particular media. When the media is a permanent storage media, loss of data can be avoided, ubiquitous read can be achieved, and selective write in predetermined drives can be achieved resulting in a robust system and method of storing and retrieving data.
Type:
Application
Filed:
October 29, 2010
Publication date:
May 12, 2011
Inventors:
Erik C. BARD, Douglas P. Hansen, Mark O. Worthington
Abstract: An information detection device includes an equalizer that equalizes the readout signal to a PR channel having equalization target levels of four or more values, and a Viterbi detector. The Viterbi detector generates branch metrics with the equalization target levels as reference levels to determine recording data from an output of the equalizer. The Viterbi detector has a mode of generating the branch metrics and determining the recording data by limiting at least one out of a maximum value and a minimum value of the equalization target levels.
Abstract: An optical system of an optical pick-up including a resin coupling lens and a resin objective lens with NA larger than 0.8, wherein, magnification ? satisfies a condition: ?0.13<?<?0.08, a focal length f of the objective lens satisfies a condition: 1.15<f<1.50, the objective lens has an annular zone structure on at least one surface of the objective lens, and the annular zone structure has a plurality of annular zones and has steps each of which extends in a direction of an optical axis of the objective lens and is formed at a boundary between adjacent ones of the plurality of annular zones to cause a predetermined optical path length difference between a light beam passing inside the boundary and a light beam passing outside the boundary, and the optical system of an optical pick-up satisfies a condition: 0.065 < ( ( ? ? 0.95 - 1.00 ) ( ? ? 0.00 - 1.00 ) × d 0 × n f 2 × ( NA 0.85 ) 4 ) P ave + 1 L < 0.
Abstract: Address information that has been error correction encoded is recorded on a second version of a recording medium after being transformed such that such that the address decoding cannot be performed by a playback device that is not compatible with the second version of the recording medium. The address decoding for the second version of the recording medium cannot be performed by the incompatible playback device (for example, a playback device that was manufactured to be compatible only with a first version of the recording medium). In other words, in the playback device that is not compatible with the second version of the recording medium, a state is created in which address errors cannot be corrected, so access is impossible (recording and playback are impossible).
Abstract: A computer readable medium, apparatus, and method for efficiently managing a space bitmap. A computer readable medium includes: a user data area on which user data is recorded; and a temporary disc management area on which a space bitmap indicating a recording status of recording and reproducing unit blocks of the user data area is recorded. The space bitmap includes header information for distinguishing an additional space bitmap from the space bitmap. The additional space bitmap is assigned when a space provided for the space bitmap is insufficient to represent the recording status of the recording and reproducing unit blocks of the user data area.
Abstract: An apparatus for generating Viterbi-processed data using an input signal obtained from reading an optical disc includes a Viterbi decoding unit and a control circuit. The Viterbi decoding unit is arranged to process the input signal and generate the Viterbi-processed data. In addition, the control circuit is arranged to control at least one component of the apparatus based upon at least one signal within the apparatus. Additionally, the component includes a phase locked loop (PLL) processing unit, an equalizer, and/or the Viterbi decoding unit. An associated apparatus including an equalizer and a Viterbi module is further provided. An associated apparatus including a Viterbi decoding unit and a control circuit is also provided. An associated apparatus including an equalizer, at least one offset/gain controller, and a Viterbi module is further provided. An associated apparatus including an equalizer, a Viterbi module, and a peak/bottom/central (PK/BM/DC) detector is also provided.
Abstract: An information storage medium according to the present invention has n information storage layers (where n is an integer and n?3), on which data can be written with a laser beam and which are stacked one upon the other. Each of the n storage layers has a test write zone for determining the recording power of the laser beam. When those n layers are counted from the one that is located most distant from the surface of the medium on which the laser beam is incident, there is a bigger radial location difference between the outer peripheral end of the inner one of the test write zones of ith and (i+1)th information storage layers (where i is an integer that satisfies 2?i?n?1) and the inner peripheral end of the other outer test write zone than between the outer peripheral end of the inner one of the test write zones of jth and (j+1)th information storage layers (where j is an integer that satisfies 1?j?i?1) and the inner peripheral end of the other outer test write zone.
Abstract: A drive apparatus of the present invention includes a recording/reproduction section and a drive control section. The drive control section at least performs a process including: receiving a recording instruction at least specifying a location at which data is to be recorded; determining whether a data recording which is performed in accordance with the recording instruction is an appending recording, a first time pseudo-overwrite recording or a second time or more pseudo-overwrite recording; generating data including location information before replacement having information set therein according to the result of the determination; and controlling the recording/reproduction section to record the data in one of the plurality of ECC clusters of the write-once recording medium.
Abstract: An object of the invention is to provide an optical recording medium and an optical information device that enable to improve the quality of a servo signal and a reproduction signal.
Abstract: A control apparatus is provided for controlling an access means for accessing a recording medium containing at least one area so that the access means accesses the at least one area. The apparatus comprises a means for determining whether or not at least one first recorded area storing data is included in the at least one area, and a means for controlling the access means. When it is determined that the at least one first recorded area is included in the at least one area, the control means controls the access means based on a result of accessing the at least one first recorded area.
Abstract: A loader module of an optical access apparatus is provided. The optical access apparatus has a main control printed circuit board (PCB). The loader module comprises an optical pick-up head, a drive unit, a first signal line, a second signal line and a non-volatile memory (NVM). The first signal line is configured to electrically connect the optical pick-up head, the drive unit and the main control PCB. The second signal line is configured to electrically connect the NVM and the main control PCB. The NVM is configured to store control information. The control information is transmitted to the main control PCB via the second signal line so that the main control PCB can control the loader module.
Abstract: An optical disc apparatus, being improved in a random access speed thereof and superior in a usability thereof, comprises: a virtual disc for memorizing data of at least one (1) pieces of an optical disc; a recording/reproducing means for executing reproduction of data from the optical disc and recording of data onto the optical disc; and a system controller means for controlling the virtual disc and the recording/reproducing means.
Abstract: A method of reproducing an audio file includes: identifying a type of audio data in the audio file based on an extension information of the audio file separated from but associated with the audio data of the audio file; and determining whether the audio file is reproducible by checking whether a part of the audio file constructs a specific format stream corresponding to the identified audio type.
Type:
Grant
Filed:
November 21, 2006
Date of Patent:
March 8, 2011
Assignee:
LG Electronics Inc.
Inventors:
Yong Hee Han, Jong In Shin, Myung Gu Lee, Han Sang Lee
Abstract: In an embodiment, an optical disk drive includes a land prepit detection circuit. With such circuit, if the optical disk drive reads a poor-quality disk on which, in terms of signals, LPP-like noises are caused by a defect of a land area, it is possible to increase the noise immunity and LPP detection accuracy of the optical disk drive so that the optical disk drive is capable of successfully detecting LPP without fail.
Abstract: A technique for investigating differences of composition and structural state of a recording layer of an optical disc along with other defects, such as scratches, contamination, warp and distortion, prior to video recording and for setting up appropriate recording conditions in compliance with this result to thereby perform recording is disclosed. In an optical disc recording device capable of recording information on an optical disc, a region to be investigated is defined based on the video recording reservation contents. Then, investigate and evaluate the disc state which can affect the recording quality in a target disc region to be recorded. Next, based on investigation/evaluation results, perform recording setup, recording speed setup, servo control setup and recording position setup to thereby perform the recording. By appropriately modifying the recording setup on a case-by-case basis, it is possible to achieve high-quality recording.
Type:
Application
Filed:
October 28, 2010
Publication date:
February 17, 2011
Applicants:
Hitachi, Ltd., Hitachi-LG Data Storage, Inc.
Abstract: An optical disc recording method for recording disc information to be used in recording/reproducing control on an optical disc, comprises the following steps of: providing a first disc information unit and a second disc information unit, each having a predetermined data size, in a predetermined management information area of the optical disc; the disc information includes write strategy information; separating the write strategy information into first write strategy information and second write strategy information; recording the first disc information into the first disc information unit; and recording the second disc information into the second disc information unit.
Abstract: An optical pickup device is provided. In an optical pickup device, a light receiving element has light receiving regions for focusing as part of the plurality of light receiving regions. A diffraction element has diffraction regions for focusing as part of the plurality of diffraction regions. A part of division lines which define the diffraction region for focusing is formed in a shape which is convex from the outer side toward the inner side with respect to the center of the incidence range on the diffraction element where a returning light beam enters. The part of the division lines formed in the shape which is convex from the outer side toward the inner side divides an incidence range on the diffraction element where a returning light beam enters, regardless of whether or not there is a focus error.
Abstract: An information recording/reproducing apparatus including an optical pickup unit for generating an RF signal performs signal processing to acquire, at a restart of recording after a halt of recording, a data ID to be used as a reference for specifying a recording restart position in the recording medium based on the RF signal. The signal processing includes reproduced signal generation processing to generate a reproduced signal based on the RF signal, and data ID acquisition determination processing to determine, at the restart of recording after the halt of recording, whether or not the data ID has been properly acquired, based on the reproduced signal. If it is determined in the data ID acquisition determination step that the data ID has not been properly acquired, a reproduction parameter to be used for generating the reproduced signal in the reproduced signal generation step is adjusted.
Abstract: The present invention aims to provide a reproduced signal evaluation method and a write adjustment method for offering a Blu-ray disc having a large storage capacity with excellent media compatibility. An evaluation index L-SEAT is calculated through signed addition using a Euclidean distance difference calculated from at least one of target signals in which a focused edge is shifted to the right and left, and the quality of the reproduced signal is evaluated based on the evaluation index. Write condition adjustment using the index enables write adjustment not depending on SNR and achieving high adjustment accuracy.
Abstract: An information recording apparatus for recording additional content on a medium on which a title including one or more files is already recorded, includes means for designating a title to be added on the medium; means for transmitting disc package information, the disc package information and unique IDs; means for receiving and additionally recording on the medium the title to be added generated in the content server, file names of files so as not to be the same as the file names of the files constituting the titles already recorded on the medium; means for receiving and additionally recording a new title for display of a menu screen on the medium, which is generated in the content server, so that the title to be added can be selected, on the basis of the disc package information; and means for receiving and additionally recording new disc package information on the medium.
Abstract: A DRM disk such as a Blu-ray stores content in a high resolution version for playing by a disk player. The disk also stores the same content in a lower resolution version for playing by a secondary device such as a Playstation Portable (PSP). The disk can be engaged with the disk player and the lower resolution format transferred to the secondary player through a mechanism such as a removable medium (e.g., a Sony Memory Stick®) or a USB connection or other means in accordance with DRM restrictions on the disk.
Abstract: A Spare Area kept unused on a disk is available for use other than spare processing, or Defect Management process, and compatibility of the disk is at least secured between different recording apparatuses. This is implemented by recording a SWP_PAC cluster defined as a new item and by recording address information of used addresses in a PAC or TDDS area.
Type:
Application
Filed:
June 14, 2010
Publication date:
January 27, 2011
Applicants:
Hitachi-LG Data Storage, Inc., Hitachi Consumer Electronics Co., Ltd.
Abstract: A method of managing data in an optical disc apparatus is provided. The type of a loaded disc is checked, and data corresponding to the checked disc type is read from a compressed file, decompressed and stored in a memory of the optical disc apparatus. Recording-related data respectively corresponding to disc types, manufacturers, and recording speeds are separately compressed in the compressed file. Identification information about the disc types, manufacturers, and recording speeds and information on positions at which the recording-related data about the disc types, manufacturers, and recording speeds are stored may be included in the head of the compressed file. The compressed file may include separately compressed servo data, and information on the position at which the servo data is stored may be included in the head of the compressed file. Accordingly, the optical disc manufacturing cost can be decreased and a data loading time can be reduced.
Abstract: A driver circuit for use with a variety of OPU circuits has both a single-ended input and a differential input. The single-ended input is coupled to a single-ended signal path having a variable gain stage and a variable level shifter. The differential input is coupled to a differential signal path having a variable gain stage and a variable level shifter. The single-ended signal path and the differential signal path may be selectively coupled to an output. The respective variable gain stages and variable level shifters can be adjusted so that an output signal at the output has a desired dynamic range.
Abstract: Target levels in the PRML method are adaptively set under conditions of simplicity and a low cost. A method of setting a target level for reproduction of an optical information recording medium includes: a step of producing a reproduction signal from reflected light of laser light irradiated to an optical information recording medium; a step of performing waveform equalization processing, which depends on a predetermined partial response characteristic, on the reproduction signal to produce a waveform-equalized reproduction signal; a step of detecting peak levels for marks and spaces of a predetermined number of symbols from the waveform-equalized reproduction signal irrespective of a condition for a symbol adjoining each symbol; and a setting step of determining and setting values of a plurality of target levels, which is employed in Viterbi decoding and is arrayed with non-equal intervals among them, on the basis of a relative relationship among the detected peak levels.
Abstract: An optical disc drive, and a method of driving the optical disc drive are provided. Where the optical disc drive has a connectivity or a compatibility with a host that is incompatible with the optical disc drive, a file system and device information accepted by the host are provided. The host may have a compatibility with limited external medium devices and a specific command set for data exchange. The optical disc drive and the method of driving the optical disc drive may transmit compatible information to the host and select the specific command set accepted by the host, so that the optical disc drive is compatible with the host.
Type:
Application
Filed:
June 24, 2010
Publication date:
December 30, 2010
Applicant:
Toshiba Samsung Storage Technology Korea Corporation
Inventors:
Soon-gyu Jeong, Dong-hwan Lim, Hyung-kyoon Kim, Dong-jin Lee, Chang-heon Kim, Won Kim
Abstract: The present invention allows usable information to be selected by comparing information regarding encoding with conditions regarding encoding processing. When delay modes, picture structures, and pulldown modes do not match each other between previous encoding time and re-encoding time, parameters are not reused. When they match and image frames do not match, a picture type is reused. When a bit rate in the previous encoding is smaller than that in the current encoding and a chroma format is larger than the current chroma format, a picture type and a motion vector are reused. When the conditions are not satisfied, parameters are supplied and received and a determination is made as to whether or not chroma formats match each other. When the chroma formats do not match each other, picture-type information, motion-vector information, and quantization-value information are reused. When the chroma formats match each other, stream data input to a decoding unit is output.
Abstract: Various embodiments of the present invention provide systems and methods for data processing. For example, a data processing circuit is disclosed that includes an increased iteration enable signal, a first detector circuit, a second detector circuit, and a data decoding circuit. The first detector circuit receives a data set and performs a data detection on the data set to provide a detected data set. The data decoding circuit receives a derivative of the detected data set and performs a decoding process to provide a decoded data set. The decoded data set is provided to the second detector circuit based at least in part on an assertion level of the increased iteration enable signal.
Abstract: A plurality of drive units are divided into two groups and controlled. While almost a half of the drive units perform recording on or reproducing from a recording layer in a first format, remaining almost half of drive units perform recording on or reproducing from a recording layer in a second format.
Abstract: An optical disk drive system associated with a laser diode is described. The optical disk drive system comprises a current generator for receiving input signals; a current switch coupled to receive timing signals; a current driver coupled to receive output signals from the current switch and the current generator, the current driver further comprising a driver with wave shape control selected from the group consisting of a laser diode read driver and a laser diode write driver, wherein the driver with shape control is operative for transmitting at least one output signal that is a scaled version of at least one of the output signals received from the current generator, wherein the current driver is operative for transmitting at least one output signal driving the laser diode.
Type:
Application
Filed:
April 12, 2010
Publication date:
December 16, 2010
Inventors:
Douglas Warren Dean, Shengyuan Li, Indumini W. Ranmuthu
Abstract: An input current channel device is described. This device comprises a first terminal for receiving a reference signal; a second terminal for receiving a first target signal; a pass through device coupled to the first terminal, the pass through device operative for transmitting a delayed reference signal in response to receiving the reference signal; a first combination logic device coupled to the first terminal and the second terminal, the first combination logic device operative for transmitting a first combination logic signal in response to receiving the reference signal and the first target signal; a selection device coupled for receiving the delayed reference signal, the first combination logic signal, and a first synchronization signal, the selection device operative for selectively transmitting a second synchronization signal, and wherein selectively transmitting the second synchronization signal reduces skew between the reference channel and the first target channel.
Type:
Application
Filed:
November 20, 2009
Publication date:
December 16, 2010
Inventors:
Shengyuan Li, Indumini W. Ranmuthu, Marius V. Dina
Abstract: An optical disc medium comprises a track groove, along which main information is recorded. The track groove is divided into a plurality of blocks. The plurality of blocks each include a plurality of frames. The plurality of frames each include one shape of wobbles indicating sub information, among a plurality of prescribed shapes of wobbles. The plurality of blocks each have address information. The address information is represented by a string of at least one piece of sub information represented by the shape of wobbles of at least one of the plurality of frames.
Abstract: A recording apparatus includes a write unit to write information data read from a memory by irradiating a disk medium with a beam in accordance with the information data, and a control unit to, upon the amount of information data stored in the memory reaching a threshold, instruct the write unit to start writing of the information data. In response to the write instruction, the write unit reads the information data stored in the memory and writes the read information data onto the disk medium while it is rotating. Upon the amount of information data in the memory decreasing to a predetermined value, the write unit stops reading and writing of the information data from the memory and onto the disk medium. The control unit sets a value of the threshold in accordance with the number of times the write unit has performed writing of the information data.
Abstract: In a case where free space of a local storage becomes smaller than a predetermined threshold while additional contents are downloaded by executing a “BD-Live” function, a screen for deleting old contents is displayed on a display. When a user deletes the old contents and the free space of the local storage becomes equal to or larger than the threshold, the screen displayed on a display is automatically erased. By repeating the deletion of old contents until download of the additional contents is completed, the entire additional contents are completely acquired.
Abstract: According to one embodiment, a write-once type information storage medium comprises an organic dye based recording material having sensitivity at a wavelength of 405 nm and at a recording wavelength in the range of 600 nm to 700 nm, wherein, when absorbance of a maximum absorption wavelength in the vicinity of 405 nm is defined as 1, the absorbance is 5% or more at any wavelength in the range of 600 nm to 700 nm.
Abstract: The present invention provides a measure for getting read/write control information stored within a space of a predetermined size in a format that ensures compatibility with media of a lower order or an older generation even if the size of the read/write control information increases significantly as the storage densities of information storage media rise in the near future. On an information storage medium, a data sequence is writable as a combination of marks and spaces. The medium has at least one information storage layer, which has an information storage area to store information and a control information area for use to perform a read/write operation on the at least one information storage layer. The control information area stores at least one set of control information, which includes a first kind of write pulse information including information to be used as a reference value and a second kind of write pulse information including information to be used as an offset value.
Abstract: A system controller of an optical disk recording and reproducing device makes a display portion display a precaution message for recommending a user to back up data recorded on the optical disk when it is determined that one or more values including a jitter value, a variation quantity of the jitter value, a block error rate and a block error rate at a particular position have exceeded precaution reference values. In addition, it makes a display portion display an urgent message for instructing a user to back up data recorded on the optical disk quickly when it is determined that one or more of the values have exceeded limit reference values.
Abstract: A method for improving readability of an optical disc includes: changing a first control parameter of an optical storage apparatus that accesses the optical disc and obtaining a plurality of associated values of an index corresponding to the readability of the optical disc for respective changed/unchanged values of the first control parameter; setting the first control parameter to be an optimal value out of the changed/unchanged values of the first control parameter according to the index; changing a second control parameter with the first parameter set to be the optimal value to obtaining a plurality of associated values of the index for respective changed/unchanged values of the second control parameter; and setting the second control parameter to be an optimal value according to the index. The control parameters having their individual optimal values are utilized for further control during decoding. In addition, an associated optical storage apparatus is further provided.
Abstract: An optical disk apparatus according to the present invention includes: a rotation driving section on which an optical disk is to be mounted and which drives the optical disk so as to be rotated; a light source; an objective lens for converging light from the light source onto an optical disk mounted on the rotation driving section; a photodetector having at least two detection sections for detecting reflected light, from the optical disk, of the light; and an error signal generation section for deriving a difference signal and a sum signal of respective outputs from the two detection sections of the photodetector, adjusting an offset in at least the sum signal among the difference signal and the sum signal, and thereafter dividing the difference signal by the sum signal whose offset has been adjusted to generate a position error signal of the objective lens.