Abstract: The position of an optical pickup with respect to a disk is maintained accurately by preventing the free end portion of a cantilever movable member from being displaced lower than its proper position during the rotation of the disk even if the movable member is heavy to have improved vibration characteristics. There are provided a movable member 4, a chassis 1, a clamp mechanism 3, and a cam mechanism 5. The cam mechanism 5 includes a shift lever 51 connected to the free end portion of the movable member 4 via elastic bodies 42 and a cam main body 55. Positioning means 8 is composed of a protrusion 53 on the shift lever 51, a stepped engaging surface 15 for supporting the protrusion 53 thereon, and a guide mechanism 71. There is also provided anti-positioning means 9 for disengaging the protrusion 53 from the engaging surface 15.

Abstract: The present invention is directed to an optical disk drive in which laser beams are emitted to an optical disk in a state of not rotated, and simultaneously an objective lens which collects the laser beams is moved to a direction approaching the optical disk at a constant speed, a time length required for moving a focused position of the laser beams from a surface of the optical disk to a recording layer is measured by observing a reflected light from the optical disk, and a type of the optical disk is determined based on the time Tdet thus measured, includes a control means which executes, a calculating process which calculates an additional travel time Tadd, based on the Tdet and an in-periphery maximum surface wobbling amount Vd of the optical disk, a moving process which further moves the objective lens for the additional travel time Tadd at the constant speed after the laser beams are focused on the recording layer, a rotating process which rotates the optical disk, a move-away process which moves the ob

Abstract: An optical disc device includes: a light source; a condensing system including a solid immersion lens for emitting light from the light source onto an optical disc; a gap control circuit for setting a distance between the solid immersion lens and the optical disc to a constant value; a CPU for adjusting a condensing position of emission light from the solid immersion lens with respect to an information recording/reproducing surface of the optical disc by moving a concave lens in a direction of an optical axis; and a focus control circuit for setting the condensing position on the information recording/reproducing surface, while following plane displacement of the information recording/reproducing surface, using a focus error signal. The CPU is operable to correct coma aberration in focus position adjustment by moving the concave lens in a direction perpendicularly intersecting with the optical axis.

Abstract: An information reproducing method using PRML technology which provides asymmetry compensation and also assures media interchangeability. To compensate for asymmetry, target levels are basically adapted to readout signals and either restriction type (1) (time reversal and level reversal symmetry) or restriction type (2) (time reversal symmetry) is imposed between target levels. As a consequence, asymmetry compensation is made regardless of a readout signal distortion such as mark shift which might deteriorate media interchangeability.

Abstract: In order to ensure recording quality while suppressing the adverse effects due to performance variations among apparatuses and disc radial positions on an optical disc, an optical disc apparatus according to the present invention performs, at the time of data recording, the steps of: acquiring a jitter value and ? value from a reproduced signal based on laser light reflected from the optical disc in relation to a disc radial position; learning a ? value when the acquired jitter value is a minimum as a target ? value; and, if a jitter value acquired thereafter is larger than the minimum jitter value by a preset reference value or above, correcting recording power based on the magnitude relation and the difference between the ? value associated with the acquired jitter value and the target ? value or performing trial record processing.

Abstract: The invention concerns the field of holographic storage units. More particularly, the invention concerns the field of holographic storage units used for bit-by-bit storage of information. It concerns a method for reading data recorded in a holographic material in the form of a hologram obtained by interference of two beams of substantially the same wavelength, and using at least one reflecting layer. The invention is characterized in that it includes the following steps: emitting a light comprising at least said wavelength at said holographic material comprising said hologram; performing a homodyne detection between the signal resulting from the first light diffracted by said hologram and at least one signal selected between the reflected signal and the signal transmitted by said at least one reflecting layer.

Abstract: An optical information apparatus according to the present invention includes: an optical system that includes a solid immersion lens (SIL) 11 and that produces near-field light to be incident on an optical disc 10; a first actuator for displacing the SIL 11; a second actuator 29 for varying the distance between the optical disc 10 and the first actuator 12 by moving the first actuator 12; a gap detecting section 18 for outputting a gap signal 19 representing the magnitude of the gap 17 between the SIL 11 and the optical disc 10; and a gap control system for controlling the first actuator 12 in response to the gap signal 19 such that the gap is maintained at a predetermined setting. The gap control system works so as to control the second actuator 29 in accordance with a signal representing the magnitude of displacement of the SIL 11 caused by the first actuator 12.

Abstract: A method for dynamic spiral ISR scheduling determines a dynamic delay with spiral to spiral spacing information of a disk, so as to ensure that the sum of a primary ISR time and a secondary ISR time does not exceed the wedge to wedge time. The ISR time may be scheduled to start after a delay for the sum of a static delay and the dynamic delay from an edge. A system for dynamic spiral ISR scheduling uses a dynamic delay determining unit to determine a dynamic delay, and an ISR scheduling unit to schedule the start of a secondary spiral set ISR based on a sum of the dynamic delay and a static delay.

Abstract: An optical head includes an objective lens held by a lens holder that is driven by a coil. The optical head includes: a base, including a mounting face having an opening portion; a substrate, operable to supply an electric power to the coil, and including a first portion; and a supporter, mounted on the mounting face, and including a second portion which faces the first portion and which is formed with a recessed portion that is connected with the opening portion.

Abstract: In an optical pickup driving mechanism using a stepping motor, a feeding operation of an optical pickup can be stabilized even in a broad operating temperature environment. In executing an optical axis correction feeding operation in response to an amount of lens shift of an objective lens of an optical pickup, a stepping motor controlling portion drives a stepping motor in a microstep drive mode to move a base of the optical pickup in a radial direction of an optical disk.

Abstract: An optical disc apparatus, comprising a tray 2, attached to be insertable within housings 9 and 10, and within the housings are included a disc motor 3, an optical pickup 4 and a moving mechanism thereof, and also a unit mechanism chassis 5 for moving the optical pickup thereon and a controller substrate 71 disposed below the unit mechanism chassis for controlling the optical pickup, and further, a wide-width flexible cable 8 for electrical connection between the controller substrate and the optical pickup, wherein the optical pickup mounts laser units 41, 42 and 43 including three (3) pieces of elements, each emitting a laser light different in the wavelength thereof, a penetrating portion 2b and a wall portion 2e are provided in a part of left bottom surface of the tray, while forming a cutoff portion 55 in a part of the chassis, thereby guiding the airflow generated accompanying with rotation of the optical disc onto the optical pickup, with certainty.

Abstract: In a super-resolution optical disk for the purpose of achieving an increase in the density of recording data by reproducing a recording mark smaller than optical resolution, the optimum reproduction power needs to be determined since the quality of a super-resolution reproduced signal strongly depends on the reproduction laser power. However, since the track error signal required for tracking servo also depends on the reproduction power, there is a need for a method for determining the reproduction power taking into account both the stabilization of tracking servo and a quality improvement of the reproduction signal. The reproduction power is changed under conditions with focusing servo applied but without application of tracking servo. Thereby, a cross track signal is detected to identify a reproduction power region that leads to quality improvement of both a reproduction signal and a track error signal.

Abstract: Aspects of the present embodiment are related to a power supply voltage supply circuit and the disk apparatus that are capable of reducing power consumption in data writing and reading. The power supply voltage supply circuit includes a data processing unit writing data onto a disk medium and/or reading data from the disk medium=having a plurality of zones assigned a cylinder number, a data input-output unit transmitting data to the data processing unit at a transfer rate in accordance with the zones, a power supply voltage supply unit supplying a voltage to the data input-output unit and a control unit controlling the power supply voltage supply unit in order to supply the voltage in accordance with the transfer rate.

Abstract: According to one embodiment, an optical disk apparatus is provided with a read section which reads data from an optical disk to output read information, a determination section which determines presence/absence of an error of the read information to output an error presence/absence signal, a transfer processing section which receives the error presence/absence signal and receives a hash request signal and transfers the hash request signal when the error presence/absence signal indicates the absence of an error, and does not transfer the hash request signal when the error presence/absence signal indicates the presence of an error, and a processing section which performs hash processing to the read information upon reception of the hash request signal.

Abstract: To record information in an optical storage medium, a pulsed laser beam produced by a laser light source is split into first and second pulsed laser beams by a beam splitter. The first pulsed laser beam to be concentrated in the optical storage medium supported by a medium support part is interrupted and resumed by a shutter. The second pulsed laser beam is received by a photosensor which produces a detection signal. A controller includes a sync-generator configured to receive the detection signal from the photosensor and to generate a synchronizing signal based upon the received detection signal, and a shutter driver configured to drive the shutter in synchronization with timing represented by the synchronizing signal generated by the sync-generator.

Abstract: A write-once optical recording medium, a method for allocating a defect management area of the write-once optical recording medium, and a method for allocating a spare area of the write-once optical recording medium are provided. A method of managing defects on a write-once optical recording medium having at least one recording layer includes the steps of allocating at least one temporary defect management area having a fixed size and at least one temporary defect management area having a variable size to said optical recording medium, respectively, recording defect management information on the at least one temporary defect management area having a fixed size and the at least one temporary defect management area having a variable size; and using the at least one temporary defect management area having a fixed size and the at least one temporary defect management area having a variable size is provided herein.

Abstract: An optimum power calibration method is provided and is implemented for writing a rewritable optical storage medium including a power calibration area. The method includes the steps of determining whether the power calibration area is recorded with data, erasing the entire power calibration area when the power calibration area is not recorded, and executing an optimum power calibration procedure. In addition, the optimum power calibration method is applied to a rewritable optical disk drive.

Abstract: A recording/reproducing head includes a laminated body facing to a recording medium, the body including a first conductive layer, a first insulating layer and a second conductive layer which are sequentially stacked. The first conductive layer generates electrons and injects the electrons into the recording medium through the first insulating layer.

Abstract: Disclosed herein is a technology that enables stable and high-speed writing and/or reading in an optical disk apparatus. The optical disk apparatus has an optical head that includes a first circuit for driving a laser diode, a second circuit for sampling and holding analog electric signals that are based on reflected laser light from the optical disk, and a third circuit for converting said signals being sampled and held into digital signals. Signals digitized in the optical head are transmitted to the apparatus body side using time-division multiplexing. The first circuit, the second circuit, and the third circuit are constructed on a single substrate or in a single IC.

Abstract: A method for determining runout disc is disclosed. The method comprises: focusing on a focal point on a disc; driving the disc to spin the disc; generating a crossover signal according to a track of the disc crossing the focal point; and determining that the disc is a runout disc when the frequency of the crossover signal exceeds a pre-determine value.