Abstract: A micro-actuator, its manufacturing method, an optical pickup head of an optical recording/reproducing apparatus having the micro-actuator, and its manufacturing method are disclosed. A low voltage and low power bi-directional driving is accomplished so that a size and a weight of a system can be considerably reduced and a response speed can be improved. A uniformity and a production efficiency are heightened by reducing a alignment tolerance. In addition, a configuration tolerance caused due to an uneven thickness of a protection layer of the record layer on the disk and an uneven smoothness of the disk is corrected, so that a focal point of an objective lens can be optimally made on a record layer of the disk.

Abstract: The present invention discloses a method for erasing a re-writable disk. The method includes determining whether the write fail occurs in a program area of the re-writable disk when fully erasing the re-writable disk and a write fail occurs. If the write fail occurs in the program area of the re-writable disk, mode 0 data can be written on locations following a location where the write fail occurs continuously since the disk is determined to be a blank disk already. And if the write fail does not occur in the program area of the re-writable disk, the optical disk drive will issue a write fail message to a host.

Abstract: In an optical disk apparatus, when a focus deviation occurs, amplitude driving of a pickup is performed for focus pull-in immediately without a waiting time. The amplitude driving is performed with a first amplitude a given number of times, and when detection of a focusing point fails, amplitude driving with a second amplitude larger than the first amplitude is performed.

Abstract: An optical pickup records data in or reproduces data from optical recording media respectively having recording faces at different heights, and includes a semiconductor laser diode array having light emitting portions for respectively emitting laser beams of different wavelengths. A finite conjugate type object lens used in this optical pickup is designed so that the numerical aperture of the object lens can be controlled to be changed in accordance with switching between the different wavelengths for allowing a laser beam to be focused on each optical recording medium.

Abstract: A strategy process used for recording data on an optical disk is also used during DC erase is performed. Effects similar to those obtained in the case, in which a high frequency signal is superposed on a laser diode output current during the DC erase, can be obtained by performing the strategy process on the laser diode output current during the DC erase. This eliminates the necessity for generating high-level and high-frequency signals. Consequently, an apparatus can be constructed at low cost.

Abstract: With respect to the disk drives provided power from a single power source in a disk drive system, start up power is first supplied to a first start-up group of the disks, preferably comprising all of the master disks, with the size of the group being selected so that the required current does not exceed the capacity of the power source. When the disk drives of the first group have substantially reached steady state, start-up is conducted with respect to a second start-up group of the disk drives so that the current required during start-up for the second group and the current required for steady state drive of the first start-up group does not exceed the capacity of the power source. With respect to each start-up group, the number of disk drives is the maximum integer value and decreases or remains the same with respect to subsequent start-up groups.

Abstract: An example dielectric information apparatus is provided with a plurality of electrodes for recording information in a small area of a dielectric substance and an earthed electrode. The electrodes are placed such that the dielectric substance is sandwiched therebetween. The dielectric information apparatus reads out the information recorded in the small area of a dielectric thin film by applying alternating current signals to the first electrodes. The polarization direction of the small area and the direction of an applied electric field decide the dielectric constant of the small area, and the oscillation frequency of an oscillator is determined by a capacitance Cs corresponding to the dielectric constant. An oscillation signal of the oscillator is demodulated at an FM demodulator, and the information is detected from the demodulated signal at a signal detector. When recording, record signals are applied to the first electrodes, and the polarization direction is set to correspond to the record signals.

Abstract: A method and apparatus renders an optical disk unplayable on a customer's optical disc playback machine. A portion of the information bearing surface of the optical disc or the light reflected therefrom, is altered for data destruction from a predetermined area, i.e., a “Table of Contents” (TOC), in order to make the disc unplayable on the playback machine of the customer.

Abstract: An optical disc drive 1 of the present invention includes an electrically rewritable flash ROM 32 which stores firmware of the optical disc drive 1; means for judging whether or not the loaded optical disc 2 is a predetermined type of optical disc in which update data for updating the currently stored firmware is stored when the optical disc 2 is loaded into the optical disc drive 1; a buffer memory 31 for temporarily storing the update data recorded in the loaded optical disc 2 in the case where the judging means judges that the loaded optical disc 2 is the predetermined type of optical disc; and control means 9 for determining whether the currently stored firmware of the optical disc drive 1 should be updated with the update data based on the absence or presence of a predetermined signal (a signal outputted when an eject button is pushed), and updating the currently stored firmware with the update data stored in the buffer memory 31 in the case where it is determined that the currently stored firmware of th

Abstract: An optical disc recording apparatus can draw an image by radially vibrating a laser beam under stable focus control. A pickup radiates the laser beam onto the optical disc rotated by a spindle motor. A focus servo controller maintains a constant spot diameter of the laser beam on the optical disc by detecting a return light of the laser beam reflected back from the optical disc. An irradiation position controller operates when the pickup opposes a label face of the optical disc for controlling an irradiation trajectory of the laser beam to vibrate in a radial direction of the optical disc while the laser beam runs along circumferential zones defined on a coloring layer of the label face. A modulating section modulates an intensity of the laser beam for forming dots along the circumferential zones so as to draw the image.

Abstract: An optical disk device comprises position control portions which carry out position control of at least one of an optical head and an objective lens based on a detection signal from the optical head, and disturbance learning portions which reduce a compensation gain of the position control portion in a range in which servo control is not deviated, and detect disturbance information of the optical disk to store it as learning disturbance information. Fine disturbance information can be reliably learned because the information is not affected by the compensation gain.

Abstract: Because of the reduced track pitch of DVD compared to that of CD, the running-OPC procedures (ROPC) currently used in CD-RW systems do not function well in recordable and rewritable DVD systems. The present invention proposes to use the reflected signal from the writing spot itself instead of the satellite spots used in the CD-RW running-OPC procedure. This is realized by sampling the RF-signal reflected from the writing spot at the high-reflective crystalline level. This sampled signal (?) is fed into a power control loop (a so-called ?-loop) to keep it at a constant level.

Abstract: An optical system of an optical pick-up, which is provided with a light source that emits a light beam, and an objective lens that converges the light beam emitted by the light source onto a data recording layer of an optical disc. The optical system satisfies a condition: 0.75<d·(M?1)/(M·L)<1.0, where d (mm) represents a thickness of the objective lens, M represents magnification of the optical system, and L (mm) represents an O/I distance which is defined as a distance between an object and an image. A beam spot suitable for the optical disc is formed by the objective lens on the data recording layer of the objective lens without using a coupling lens.

Abstract: A method for minimizing spherical aberration in an optical read/write drive caused by variances in lens thickness and laser wavelength. The method provides an economic solution that pairs objective lenses with laser diodes such that the spherical aberration caused by the objective lens is offset by the spherical aberration caused by the laser wavelength, thereby minimizing or completely canceling the overall spherical aberration.

Abstract: A storage medium initializing method includes the steps of detecting a mode corresponding to a recording format to be loaded on a storage medium; and initializing the storage medium according to the mode detected in the detecting step. A recording and reproducing method and apparatus are configured to detect a type of storage medium loaded onto the apparatus and adjust the recording and reproducing processes accordingly.

Abstract: An optical recording medium and a recording system for the same are provided, which can dissipate heat produced by a laser beam during recording operations to thereby increase the erasing power margin of the laser beam which allows the playback jitter value to take on a certain value or less. A recording system 1 includes an optical recording medium 10 and an optical recording apparatus 30. The optical recording medium 10 has a reflective film 16, a second dielectric layer 18, a recording layer 20, a heat sink layer 24, and a light-transmitting layer 26, which are formed on a support substrate 12. The heat sink layer 24 is made of a material having a certain range of thermal conductivity, e.g., alumina. The optical recording apparatus 30 allows a laser beam of 450 nm or less in wavelength to be incident from the light-transmitting layer 26 via a lens system having an objective lens with a numerical aperture of 0.7 or more.

Abstract: A method for adjusting a reference level of an analog signal from a plurality of periodically sampled points includes the following steps. Firstly, a first level shift from an preliminary reference level to the last second sampled point within a specified period and a second level shift from the preliminary reference level to the last sampled point within the specified period is determined when one of a first level of the last second sampled point and a second level of the last sampled point is higher than the preliminary reference level and the other is lower than the preliminary reference level. Then, the preliminary reference level is moved toward the first level when an absolute value of the first level shift is greater than an absolute value of the second level shift, and the preliminary reference level is moved toward the second level when the absolute value of the first level shift is less than the absolute value of the second level shift, thereby defining an adjusted reference level.

Abstract: An environmental load information of an information recording medium is recorded on the information recording medium so as to recycle or dispose properly an information recording medium, which is not necessary any more. The information recording medium comprises a main information area (102) for recording or reproducing information and a recording area (101) for environmental load information, which is recorded with an environmental load information of the information recording medium.

Abstract: A method and a recording device for formatting arid recording on a multi-layer phase-change type optical disc include recording areas on first and second layers of the optical disc according to a predefined sequence, so that an area of the first layer where an incident radiation beam passes through is always fully written or fully empty when recording on the second layer.

Abstract: An optical pickup converts a laser beam from a semiconductor laser (1) into a parallel ray with a collimator lens (2), and divides it into a main beam (30), a sub-beam (+1st order component) (31), and a sub-beam (?1st order component) (32) with a gradient multiple-division type phase difference grating (3). After passing through a beam splitter (4), an objective lens (5) condenses the light beams on a track (61) of an optical disc (6), and the reflected light that has passed through the objective lens 5 is reflected at the beam splitter (4) and is guided into optical detectors (8A, 8B, and 8C) by a condensing lens (7). Accordingly, in a tracking error signal detecting method using the push-pull signals of the main beam and sub-beams, an offset produced by an objective lens shift or a disc tilt can be cancelled at low cost without lowering the efficiency of using light.