Abstract: An optical positioning circuit includes an electro-optic positioner which positions an optical beam on an optical medium to read/write patterns of data on the optical medium, and a driver circuit, such as an inductive capacitive circuit, which drives the electro-optic positioner. The optical medium has a dimension along which the optical medium is moved, and each of the micropatterns extends along less than (e.g., {fraction (1/10)}th of) that dimension.

Abstract: The present invention relates to an apparatus for reading from and/or writing to optical recording media having a scanner for scanning the recording medium, a coarse drive for moving the scanner relative to the recording medium and a measuring device for determining the travel of the scanner. The object of the present invention is to propose an apparatus of this type in which it is possible to determine the position of the scanner as exactly as possible, the intention being for this to be ensured even in the event of a high movement speed or acceleration. This is achieved according to the invention by virtue of the fact that the measuring device has an optical interference generating means and an optical interference detection means. The invention is particularly advantageous for apparatuses which require rapid access to extremely diverse locations on the recording medium, as is the case with apparatuses appertaining to optical data storage, for example CD-ROM or DVD-ROM apparatuses.

Abstract: In a method for optical data storage, a write/read device is employed with a first optical lens system consisting of an array of lenslets which are associated with one or more areas on a data-carrying medium which forms part of the optical data memory. During writing/reading of data in the data-carrying medium the optical data medium is positioned on one or more reference surfaces. When localizing or reading data which are stored in an optical data memory in this fashion, the data-carrying medium is brought in register with the first optical lens system in the write/read device, whereupon light from the write/read device passes through a set of angular coordinates, the optical response from the data-carrying medium being detected simultaneously and in parallel by means of the write/read device.

Abstract: A recording apparatus of a master disc of optical discs which can irradiate a recording beam to a preferable position on the master disc even when a vibration occurs in a rotary shaft to hold the master disc or when a rotational fluctuation occurs in a spindle motor. An angle position in the rotating direction of the rotary shaft and a displacement of the rotary shaft in a radial direction of the master disc are detected. Based on the angle position and the displacement, the present deviation at the present angle position from the reference position of the rotary shaft is calculated. Based on the present deviation, the irradiating spot position is adjusted.

Abstract: An optical pickup device includes a light source for generating light, a light path changing means for changing the traveling path of incident light, an objective lens for focusing incident light to form a light spot on a recording medium and having an incidence region of a predetermined size, a tracking mirror disposed on the light path between the light path changing means and the objective lens, for reflecting incident light emitted from the light source so that the light spot traces proper track positions of the recording medium, a lens unit consisting of at least two lenses which allow the light reflected from the tracking mirror to be incident on the incidence region of the objective lens, and a photo detecting unit for receiving light reflected from the recording medium and having passed through the objective lens and the light path changing means.

Abstract: At a step S4 of a flowchart representing the operation of a disk drive, a recording or playback operation requested by the user is carried out. Then, the flow of the operation goes on to a step S5 to form a judgment as to whether or not to correct focus precision. If the focus precision is to be corrected, the flow of the operations goes on to a step S6 at which a command is issued to move an optical pickup from the current position to a location preceding the current position by 1 track. At the next step S7, the focus precision is corrected by playing back data already recorded on the location preceding the current position by 1 track.

Abstract: A pickup apparatus 1 is directed to an apparatus for optically reading-out information on a disk 3 arranged in a disk player, and comprises a pickup 11, an LD 13, a half mirror 15, a photo detector 17, and a pickup frame 19. The 11 is for irradiating a light on the 3 and for receiving the light reflected from the 3. The 13 is for transmitting the light to the 11. The 15 is a plate shape member for reflecting the light outputted from the 13 and for transmitting the light to the 11, that the light from the 11 permeate. The light permeating through the 15 incidents on the 17. The 11, the 13, and the 17 are fixed on the 19 at predetermined positions. A side part of the 15 is fixed to the 19 at three points by using an adhesive agent.

Abstract: An objective lens driving apparatus having a focusing coil and a tracking coil arranged in a parallel relationship with a thin, flat shape so that both the focusing coil and the tracking coil can be moved by a single flat magnet. An objective lens supporting member supports the objective lens, and is movably supported on a stationary member. A drive motor is provided at least one side of the objective lens supporting member. A yoke is fixed to the stationary member, and a drive magnet is mounted to the yoke. The drive magnet has a flat surface parallel to both the focusing direction and the tracking direction, the flat surface having four single-pole areas each of which is magnetized in a direction perpendicular to the flat surface. A drive coil assembly including the focusing coil and the tracking coil is mounted on the objective lens supporting member.

Abstract: An optical pick-up device 1 comprises a laser diode 2 for recording which acts as a fixation side light source attached to an attachment portion 5 of a device frame 4 and has a great calorific value, and a laser diode 3 for reproduction which acts as an adjustment side light source held in a holder 6 fixed with an adhesive 7 in a clearance 46 provided on a side surface 45 of the device frame. Heat generated from the laser diode 2 for recording is radiated efficiently through the device frame 4, and heat generated from the laser diode 3 is also radiated efficiently through the holder 6 fixed with the adhesive 7 which is partially filled for the device frame 4 with the clearance 46 formed.

Abstract: A first pair of light-receiving cells and a second pair of light-receiving cells are diagonally arranged to constitute a quadrifid light-receiving cells. A pair of first wiring patterns are respectively connected to the first pair of light-receiving cells for leading out output signals therefrom. A pair of second wiring patterns are respectively connected to the second pair of light-receiving cells for leading out output signals therefrom. The first wiring patterns are arranged adjacent to each other, and the second wiring patterns are arranged adjacent to each other. A third wiring pattern is arranged between the first and second wiring patterns, in which a signal having a different nature from those of the output signals from the light-receiving cells.

Abstract: An optical pickup for an optical storage device includes a stem, a substrate mounted on the stem, and a laser diode mounted on the substrate. The substrate is integrally formed with an optical signal detector and an error signal detector for focusing error detection and tracking error detection. A cap is mounted on the stem so as to accommodate the substrate and the laser diode. A beam splitter unit including a polarization beam splitter and a beam splitting element is mounted on the cap. A hologram for diffracting a reflected beam toward the error signal detector is interposed between the cap and the beam splitter unit. The substrate is biased at a given potential, and has an insulating film opposed to the stem.

Abstract: A reproduction power test method for setting an optimal power of a reproduction light beam for reproducing an information from a domain wall displacement type magneto-optical medium comprises the steps of detecting a domain wall displacement start reproduction power Prwd at which the domain wall starts to be displaced, and a maximum reproduction power Prmax allowing the domain wall displacement, and setting an optimal reproduction power Pr based on the obtained domain wall displacement start reproduction power Prdwd and maximum reproduction power Prmax.

Abstract: A bias voltage controlling apparatus controls a bias voltage for a focus servo control to control a position of a focal point of a light beam, which is irradiated onto an information record surface of an information record medium, in a direction perpendicular to the information record surface. The bias voltage controlling apparatus is provided with: a distinguishing device for distinguishing a type of the information record medium; and a controlling device for optimally controlling the bias voltage on the basis of the type of the information record medium distinguished by the distinguishing device.

Abstract: An optical disk drive for reading and/or writing information from/on an optical disk includes an auxiliary lens to compensate for optical aberrations and a servo loop for positioning the auxiliary lens relative to a main lens. The servo loop includes an actuator for driving the auxiliary lens and a controller to feed the actuator coil with a drive current dependent on a position signal which is derived from the actual inductance of the actuator coil and a reference signal which indicates a desired position of the scan element. The disk drive also includes an inductance influencing device to vary the inductance of the actuator coil as a function of the position of the scan element.

Abstract: A magneto-optical disk drive incorporates: a structure to mount a front panel to a frame using a cartridge loading system, using a set of linearly movable control cam plates, to draw a cartridge into a cartridge holder and then to move the cartridge holder to an operating position; a timing control system for the cartridge loading system, which includes a unitary encoder cam gear including a drive gear portion to move the cam plates to lift and lower the cartridge holder, a cam groove portion to draw a cartridge into the cartridge holder, and timing encoders portions to interrupt photo sensors; a shutter mechanism to fully close a cartridge slot with a shutter, both when the drive holds a cartridge and when empty; a magnetic head vertical positioning system to position a magnetic head base against fixed reference surfaces below and a set of resilient members above; a magnetic head horizontal positioning system to first fix the magnetic head base to rotate horizontally about a point, and then to resiliently ho

Abstract: An optical drive system includes an optical assembly, a light source, a lens positioned to direct light between the optical assembly and an information storage medium or disc, and an actuator suspending the lens. A photodetector is disposed in a path of returning light to measure light received from the medium. A monitoring circuit is provided to monitor a Quad Sum signal associated with return light. A first servomotor is employed to move the lens in a tracking direction and to move the lens during focus capture while system circuitry searches for a maximum Quad Sum signal. A second servomotor is employed to move the lens in a focusing direction. A first electronic circuit is provided to control the first and second servomotors.

Abstract: A method is proposed which serves to control the focusing of a light beam, aimed at a rotating recording medium (25) for reading data, of a scanner (15, 20) onto the recording medium (25) and the guidance of the light beam along the data tracks of the recording medium (25), each by means of a respective control circuit. The scanner (15, 20) and the recording medium (25) are mounted on a fundamental substrate (10) in at least one housing (1), and the at least one housing (1), together with the fundamental substrate (10), the scanner (15, 20) and the recording medium (25), forms a coupled mechanical oscillator, which is vibrated as a function of a vibration spectrum (75); the scanner (15, 20) is accelerated by the vibration and a relative motion of the recording medium (25) with respect to the scanner (15, 20) is effected, and the amplitudes of the relative motion and the accelerations have a frequency response.

Abstract: A tracking mechanism for an apparatus which records and/or reproduces data on and/or from a medium through a relative scan of the medium with probes, the medium being formed with a plurality of tracking bit trains disposed in parallel at a predetermined distance between trains, the tracking mechanism having: a plurality of probes disposed at a predetermined distance between probes; and a tracking controller for performing a tracking control in accordance with outputs from the plurality of probes, the outputs being obtained when the plurality of tracking bit trains are scanned with the plurality of probes. A tracking method for such an apparatus includes the steps of: scanning the plurality of tracking bit trains with a plurality of probes disposed at a predetermined distance between probes; and performing a tracking control in accordance with outputs from the plurality of probes, the outputs being obtained when the plurality of tracking bit trains are scanned with the plurality of probes.

Abstract: The present invention relates to a method and to a device for automatically correcting, in a single application, positioning errors of optical elements of an optical system, with respect to the optical axis of said system. According to the invention, said device (1) has means (A1, A2, Am) for taking measurements representative of image shifts with respect to said optical axis, a calculation unit (UC) for determining on the basis of said measurements, values representative of positioning errors of optical elements, and means (C1, C2, Cn) for automatically modifying the positioning of said optical elements on the basis of these values.

Abstract: An optical head device capable of stably positioning an information head device even if a distance between the object point and the image point is reduced so as to miniaturize the device can be realized. The optical head device comprises a semiconductor laser emitting a light beam, a lens converging the light beam emitted from the semiconductor laser to a disk and a holding means maintaining the disk at a constant distance from the lens. The optical head device satisfies the following equations 24 and 25: L2=f×L1/(L1−f)  (equation 24) h<L2  (equation 25) wherein f denotes a focal length of the lens, L1 denotes a distance between the semiconductor laser and a first principal point located on the semiconductor laser side of the lens and h denotes a distance between a second principal point located on the disk side of the lens and the disk that is held by the holding means.