Abstract: A link writing method for a recordable or rewritable compact disk includes recording a writing interruption address and enabling a succeeding writing process after the writing interruption. Enabling a succeeding writing process includes searching the linking area and enabling a start writing signal and activating a laser power. The method can link a succeeding writing area with a previously written interrupted area with sufficient accuracy to allow the data frame to be successfully processed by error correction within the host drive. The linking area may be positioned by counting the values of the interrupted block, the interrupted data frame, and the interrupted bit count or by detecting a blank area. Other techniques for positioning the linking area include detecting an unwritten area having a length greater than a maximum or writing a characteristic pattern after an interruption.

Abstract: An information recording device comprising at least a recording pulse generating means and a recording pulse selecting means capable of generating various multi-pulses each of which is a combination of a leading heating pulse and a succeeding heating pulse, and rectangular pulses each of which is a single pulse, as a recording pulse, is disclosed. The recording pulse selecting means switches and selects among the multi-pulses and the rectangular pulses according to a recording condition, and then causes a light emission of a laser light source through a light source driving means. Even though in a high recording linear velocity recording condition that is insufficient in power for the recommended multi-pulse recording, a very low recording power can still be used by switching to the rectangular pulse recording, so as to achieve a recording with a much higher recording speed. In addition, good recording marks can be formed without exceeding a maximum allowable recording power.

Abstract: In the optical disc apparatus according to the present invention, the CPU 113 is operated to execute a control program stored in the ROM 112 to calculate a reproduction time at the time point when the power supply was turned off based on parameters after reading out from the DRAM 111 the parameters at the time point when the power supply was turned off. The CPU 113 is then operated to execute the control program stored in the ROM 112 to produce a control signal to have a display unit, not shown, display the reproduction time thus calculated, and calculate a reproduction position at the time point when the power supply was turned off based on parameters indicative of the address number and produce a control signal to have the reproduction of the reproduction information such as, for example, audio data and image data resumed.

Abstract: After the initiation of writing, an output signal from an LPF is sampled in correspondence with a portion with a predetermined pulse width of recording data, so as to obtain a pit level. In the resultant signal, its varying portions which correspond to the multi-pulse trains of the write signal are smoothed. A controller modifies a level of a target level signal to be supplied to an APC circuit in such a manner that the pit level becomes an optimum pit level which has been obtained prior to the initiation of writing.

Abstract: A compatible optical pickup compatibly using a high density recording medium and at least one low density recording medium, includes an objective lens to form a light spot suitable for use on a recording surface of the high density recording medium by focusing a corresponding incident light beam with a high NA suitable for the high density recording medium and a light spot suitable for use on another recording surface of the low density recording medium by focusing another corresponding incident light beam, and an actuator provided to apply tilt to the objective lens. The light beam for the low density recording medium is incident on the objective lens as a divergent beam. When the objective lens is shifted in a radial direction, a tilt is applied to the objective lens corresponding to the shift.

Abstract: A method of recording data optically to an optical disk having a plurality of sectors, in which each sector has a region to be recorded with data, the data is recorded in units of blocks, and the block includes a predetermined number of sectors and is a data unit including error correction codes. In recording data related to a content by dividing and recording the data in a plurality of sectors continuously, dummy data to be used for extracting a clock in PLL for data reproduction is recorded on a region adjacent before a sector from which data recording is started. The data related to the contents is recorded on sectors following the region recorded with the dummy data.

Abstract: A pickup drive unit is provided including at least a rack portion provided thereon with gear teeth to be engaged with grooves of a lead screw; a plate-shaped connecting portion made of a flexible material for connecting the rack portion to a fixing portion tightened to a pickup and for supporting the rack portion in a cantilever fashion to be deformable in a direction of either bringing close to, or removing from, the lead screw; and a compressed coil spring for applying a force pressing the rack portion against the lead screw; in which the distance on the plate-shaped connecting portion from an end on the side of the fixing portion to the contact portion between the gear teeth and the lead screw is made smaller than the distance from an end on the side of said fixing portion to another end on the side of the rack portion.

Abstract: In order to protect copyrighted data on a disk, a method and apparatus for generating a burst cutting area (BCA) on a disk to prevent unauthorized copy, and an information storage medium having a BCA are provided. The information storage medium comprises: a user data recording area; and a burst cutting area (BCA) on which control information is modulated by using on-off keying (OOK) modulation and recorded. According to the method and apparatus, channel bits after BCA data modulation are generated by inserting a start pattern to data bits before modulation such that a separate modulation table is not needed. Accordingly, the recording density in the BCA increases and by using the start pattern, a sync pattern distinguishable from data is generated and can be used as a signal for a phase locked loop (PLL) when data is restored.

Abstract: A method of recording data optically to an optical disk having a plurality of sectors, in which each sector has a region to be recorded with data, the data is recorded in units of blocks, and the block includes a predetermined number of sectors and is a data unit including error correction codes. In recording data related to a content by dividing and recording the data in a plurality of sectors continuously, dummy data to be used for extracting a clock in PLL for data reproduction is recorded on a region adjacent before a sector from which data recording is started. The data related to the contents is recorded on sectors following the region recorded with the dummy data.

Abstract: An optical head device including a lens holder which holds an objective lens, six wires for supporting the lens holder and a holder support member which movably supports the lens holder by the six wires in a tracking, focusing and tilt direction. The six wires comprise two pairs, each of the pairs comprising a composite wire composed of two wires and a single wire composed of one wire which are respectively disposed on an upper side and a lower side of the lens holder in the focusing direction. The spring constant of the composite wire is set to be approximately equal to a spring constant of the single wire. Alternatively, the six wires may be disposed on the same circumference with respect to a drive center in the tilt direction or the spring constant of one wire of the pair may be set to be smaller than spring constants of the other two wires of the pair.

Abstract: A method and apparatus for realizing a stable focus jump operation even in a case where a waveform of an S-curve of a focus error signal fluctuates due to aberration due to fluctuation of a multilayer optical disk substrate thickness or the level of the S-curve fluctuates due to reflectance fluctuation are provided.

Abstract: An objective lens of an optical pickup apparatus converges a divergent light flux onto an information recording surface. The following conditional formula is satisfied: |?SA1/?U|·|?U|+|?SA2/?T|·|?T|?0.07 ?rms where ? represents a wavelength of a light source, ?SA1/?U represents a change of a spherical aberration for an object-to-image distance change ?U (|?U|?0.5 mm) and ?SA2/?T represents a change of spherical aberration for a temperature change ?T (|?T|?30° C.), the object-to-image distance is a distance between the light source (a light emitting point) and the information recording surface.

Abstract: On a disc master DS, a record mark is formed at a displaced position to which the record mark is displaced, in a direction crossing the reading direction thereof, according to a wobble signal. The wobble signal is obtained by modulating the second data including an irregularly patterned bit row in a predetermined modulating method.

Abstract: A link writing method for a recordable or rewritable compact disk includes recording a writing interruption address and enabling a succeeding writing process after the writing interruption. Enabling a succeeding writing process includes searching the linking area and enabling a start writing signal and activating a laser power. The method can link a succeeding writing area with a previously written interrupted area with sufficient accuracy to allow the data frame to be successfully processed by error correction within the host drive. The linking area may be positioned by counting the values of the interrupted block, the interrupted data frame, and the interrupted bit count or by detecting a blank area. Other techniques for positioning the linking area include detecting an unwritten area having a length greater than a maximum or writing a characteristic pattern after an interruption.

Abstract: On a disc master DS, a record mark having a variable length according to the first data is formed at a displaced position to which the record mark is displaced, in a direction crossing the reading direction thereof, according to a wobble signal obtained by modulating the second data in a predetermined modulating method. The original data is recorded in such a manner that the original data is divided into the first data and the second data.

Abstract: An information recording method records information in an information recording medium by acquiring driving power supply information related to a driving power supply of an information recording apparatus which records the information in the information recording medium, in response to a request for a process which accompanies recording of dummy data in the information recording medium, and determining whether to permit or prohibit the process which accompanies recording of the dummy data, based on the driving power supply information.

Abstract: In an optical disk apparatus for focusing a light beam on a track of an optical disk by using a tracking control loop to perform at least one of recording and reproducing operations upon the optical disk, a loop level calculating unit calculates loop levels of the tracking control loop. A control unit calculates a loop gain of the tracking control loop in accordance with the loop levels of the tracking control loop and compensates for a radial tilt of the optical disk in accordance with the calculated loop gain of the tracking control loop.

Abstract: A hybrid head to record and reproduce high density data. The hybrid head to record and reproduce data includes an element to record and reproduce data which is formed at the back side of a slider. The element to record and reproduce data includes an energy source to supply energy required to heat a predetermined region of a recording medium to be data-recorded, a magnetic field applier to apply a magnetic field to the predetermined region of the recording medium heated by the energy supplied from the energy source, a data reproducer to reproduce data from the recording medium, a channel to allow the magnetic field supplier to transmit the energy supplied from the energy source to the predetermined region of the recording medium, a heat shield element to prevent heat from being transmitted from the channel to other elements around the channel, a write pole covering the heat shield element, and a magnetic field generator to generate a magnetic field to the write pole.

Abstract: An optical disc drive includes a light source, a lens, a focusing section, a spherical aberration corrector, a focus signal generator, a gain calculator and a processor. The focusing section forms a beam spot in a focusing state on the information storage layer of an optical disc by controlling the position of the lens. The spherical aberration corrector changes a spherical aberration with the beam spot in a focusing state according to a drive value of a driving signal supplied to the spherical aberration corrector. The focus signal generator generates a focus signal representing the focusing state of the beam spot. The gain calculator calculates a loop gain of a focus control system in response to the focus signal. The processor determines the drive value for the spherical aberration corrector by the loop gain.

Abstract: An optical disk device in which the laser beam emitted from a laser light source and deflected by a movable mirror is focused on an optical recording medium by an optical head section. Tracking control is carried out by a drive control section based on the laser beam reflected from the optical recording medium. A micro electrical mechanical system incorporating the movable mirror is housed in a package accommodating the laser light source. The movable mirror is driven by electrostatic force at a frequency of 0.5 KHz or higher.