Abstract: An information storage system is described which comprises a reading device (6) and an optical record carrier (5) having at least two information planes (1, 2, 3). The radiation from the record carrier is converted in a detection system (15) into a detection signal (16) which is applied to a detection circuit (17). In order that this circuit can derive the read information from the detection signal in a reliable manner, the interference signals generated by the information planes which are not to be read should comply with a requirement, referred to as the interference requirement, which is characteristic of the detection circuit. Values for the parameters of the record carrier, such as the thickness of the layers between the information planes and the reflection and transmission coefficients of the information planes then follow from this interference requirement.

Abstract: The data structure includes a navigation area of a computer readable medium storing navigation data associated with a data stream representing a portion of at least one reproduction path. The navigation data includes indication information, and the indication information indicates whether the data stream represents multiple reproduction paths or the data stream represents a single reproduction path. If the indication information indicates the data stream represents multiple reproduction paths, the navigation data includes path number information and an indicator associated with each reproduction path. The path number information identifies a number of the multiple reproduction paths, and each indicator indicates a file associated with the associated one of the multiple reproduction paths.

Abstract: An apparatus for recording and reproducing an information signal on and from an optical disc includes a memory. The information signal is written into the memory. The information signal is read out from the memory. An optical head generates a laser beam in response to the readout information signal, and applies the laser beam to the optical disc to record the readout information signal on the optical disc. A test signal is recorded on a position of the optical disc near a recording position thereof via the optical head during the writing of the information signal into the memory. The test signal is reproduced from the optical disc. The reproduced test signal is evaluated to generate an evaluation result. An intensity of the laser beam is optimized in response to the evaluation result.

Abstract: The present invention provides a method for detecting disk defects of a blank optical disk in a recording and reproducing system when a data-recording operation is performed. In the embodiment, an ATIP and the carrier signal of the ATIP signal, ATFM signals, are compared to obtain a difference between these two signals. A wobble defect flag signal is set if the difference keeps higher than a predetermined threshold for a predetermined time interval. On the contrary, the wobble defect flag signal is cleared if the difference keeps lower than the predetermined threshold for the predetermined time interval.

Abstract: An optical recording method and apparatus with different recording rates are provided for effectively increasing the average recording rate. The optical recording method includes the steps of: controlling a recording rate with a constant linear velocity (CLV) control mode; recording data; judging whether the recording rate has to be increased according to a rotating speed of a spindle motor or a recording position; and performing a process for changing the rotating speed if the recording rate is increased, and continuing recording data at the same recording rate if the recording rate is not increased. The step for changing the rotating speed includes the steps of: pausing recording data; registering a paused zone of a disc; determining a new rotating speed of the spindle motor, and driving the spindle motor at the new rotating speed; and linking recording zones to continue recording data at a new recording rate from the paused zone, when the rotating speed of the spindle motor is stable.

Abstract: A temporary defect management area 14 is placed between a control information recording area 12 and a data area 11. Before a recording medium 10 is finalized, defect management information is temporarily recorded into the temporary defect management area. Upon finalizing, the defect management information is recorded into a definite defect management area 13 placed in the control information recording area.

Abstract: An actuator of an optical pick-up device includes two fixing frames, a lens holder disposed between the fixing frames and provided with a focusing lens, coils, and a reflection mirror having a central portion thinner than other portions where the coils are located, springs supporting the lens holder, the springs connecting two points of each fixing frame to the lens holder, each spring having one or more bends, a permanent magnet disposed facing the coils to generate magnetic field, and a yoke forming a path of the magnetic field generated by the permanent magnet.

Abstract: The present invention discloses a system and method to telephonically access information related with items printed on a physical document, simply by touching with a finger items marked on the physical document or on any other physical surface. The system includes a touch foil placed over (or under) the document, for reading the coordinates of selected marked items, a telephone set for receiving the coordinates of the items selected by the user and for dialing to an interactive voice response (IVR) service used for accessing and retrieving selected hyperlinked documents from the web through a documents proxy server, for converting retrieved documents to synthesized speech, and for providing to the user through the telephone network, the selected documents that have been converted into speech.

Abstract: A system for page-based optical data storage includes a sensor array positioned to track a data page when the data page is optically read from or recorded to a storage medium. A servo mechanism is used to position the sensor array. A plurality of alignment points are defined relative to the photodetector pixel array. An alignment arrangement is located at each alignment point. The sensor array further includes servo-feedback signal generation logic operative to drive the servo mechanism based on error signals from the alignment arrangements, thereby aligning the two-dimensional photodetector array with respect to the two-dimensional data page.

Abstract: A disk recorder/player (1) including a skew adjusting means of a thin design is provided which includes a base (101), a disk rotation driving mechanism (102) for an optical disk (4), an optical pickup (103), first and second guide shafts (105, 106) to support the optical pickup (103) at opposite ends of the latter, an optical pickup moving means (104) guided by the first and second guide shafts (105, 106) in moving the optical pickup (103) radially of the optical disk (4), an elastic member (126) put in contact with the first and second guide shafts (105, 106) to force the first and second guide shafts (105, 106) in a direction generally perpendicular to the main side of the optical disk (4), an adjusting screw (127) put into contact with the first and second guide shafts (105, 106) from the opposite side of the elastic member (126) to move the first and second guide shafts (105, 106) in a direction opposite to the direction of forcing by the elastic member (126), and a skew adjusting means (109) which adjust

Abstract: A method of reproducing an audio file includes: applying a reproducing mode established based on an attribute information; obtaining at least a part of the audio file under the established reproducing mode; and determining whether the audio file is reproducible under the established reproducing mode by checking whether the part of the audio file constructs a specific format stream corresponding to the applied reproducing mode.

Abstract: Disclosed is an apparatus which includes a tracking error detection circuit, for detecting tracking error signal from outputs of a photodetector, a peak/bottom detection circuit for detecting peak and bottom values of the tracking error signal, a difference circuit for finding the difference between a peak value and a bottom value, and a comparator for comparing an output of the difference circuit with a preset reference voltage VR to output a tracking-off signal based on the result of comparison. The comparator outputs the tracking-off signal, indicating the tracking-off of the light beam spot with respect to a track.

Abstract: In a write-once recording medium, an optimum updating of the management information and a simple matching processing are to be achieved. To this end, in a system of a write-once medium, rendered accessible at random by employing the write/non-write indicating information, the management information, including a space bitmap and the last recording position information (LRA) indicating the last position of the recorded user data, is updated on the disc responsive to the generation or extinction of a gap (unrecorded area) in a region ahead of the LRA. The state of matching between the management information on the disc and the recording state of the user data is confirmed, responsive to the updating of the management information on the disc by the generation or extinction of the gap in the management information, by detecting whether or not the gap in the management information (gap indicated by the space bitmap) or the LRA is coincident with the gap or the LRA on the actual disc.

Abstract: An optical information recording method records information with respect to an optical information recording medium having a multi-layer structure recording layer formed by a plurality of recording layers each capable of recording information, and carries out an Optimum Power Control (OPC) prior to carrying out the recording. Recording conditions that are used when carrying out the OPC are read from one of the recording layers of the optical information recording medium to which the recording is to be made, where each of the recording layers is recorded with the recording conditions therefor, and the OPC is carried out using the read recording conditions.

Abstract: An extracting circuit for extracting meta information from information forming contents is provided. The meta information extracted by the extracting circuit is recorded in a recording medium together with the contents and is used as management information. With this configuration, an object can be searched for based on the contents of the object in a recording device for recording contents, such as moving and still pictures, voices, graphics, and text, in a recording medium.

Abstract: A spherical aberration compensation actuator and an optical pickup system are provided. The spherical aberration compensation actuator mounts an element for compensating a spherical aberration and operates to a single-axis direction on an optical path using electromagnetic force. The optical pickup system includes a laser diode, an object lens, a spherical aberration compensation actuator, an optical path changer, and an optical detector. The spherical aberration compensation actuator is installed on an optical path between the laser diode and the object lens and includes a lens holder having a spherical aberration compensation element for compensating a spherical aberration generated due to light passing through the object lens and operating in an optical-axis direction using electromagnetic force.

Abstract: A laser diode drive circuit for an optical disc recording and/or reproducing apparatus includes a plurality of laser diodes to output laser beams having different wavelengths, a switch circuit for selectively connecting a required laser diode from a plurality of laser diodes, a laser diode drive power supply circuit for driving the laser diode selectively connected by the switch circuit, a photodiode for detecting at least part of laser beams emitted from the laser diode to convert a detected part of laser beams into an electrical signal, a plurality of current-to-voltage conversion amplifiers connected to an output of the photodiode and whose conversion resistance values can be adjusted and having differently designed center conversion resistance values and an automatic power control circuit connected to outputs of the current-to-voltage conversion amplifiers to output a feedback signal to the laser diode drive power supply circuit.

Abstract: An optical disc recording/reproduction apparatus for recording and/or reproducing a data by applying a beam from an optical head unit through a substrate onto/from a recording layer of the optical disc through, wherein the substrate of the optical disc is 0.3 mm or below; the optical head unit comprises: an objective lens for converging an incident beam and emitting the beam toward the optical disc; a forward lens for converging the beam introduced through the objective lens and applying the beam to the optical disc; a lens holder where the objective lens and the forward lens are fixed; and an actuator for driving the objective lens and the forward lens as a unitary block and controlling at least focusing, the objective lens and the forward lens having a total numerical aperture of 0.8 or above.

Abstract: An optical disc having marks for dispersed addresses that can be easily detected with high precision. A dispersed address comprises synchronization marks, positive marks, and negative marks. Synchronization marks, positive marks, and negative marks are formed along a groove as partial discontinuities or partial modifications in the wobbled groove.

Abstract: In a optical head, a beam is emitted from a light emitting element in which a plurality of light sources are integrally formed, the light sources being able to emit beams having different wave lengths from one another. An optical system converges the beam coming from any one of the light sources onto an optical information storage medium. An optical separator separates a reflected beam coming from the optical information storage medium from the beam coming from the light source. A light receiving element detects light quantities of the reflected beam separated by the optical separator.