Abstract: The present invention provides a method for recording/reproducing information on/from an optical disc, wherein the optical disc has a first to an n-th recording layers (n is an integer of 2 or greater) laminated on a substrate, each of the first to the n-th layers having data regions segmented into a first to an m-th data zone groups (m is an integer of 2 or greater) along a radial direction of the optical disc, each of the first to the m-th data zone groups including at least one data zone, the method comprising the steps of: a) recording/reproducing information in/from data zone groups from a j-th data zone group of a first recording layer to a j-th data zone group of an n-th recording layer; and b) repeating step a) for j=1, 2, . . . , m.

Abstract: The present invention provides a method for recording/reproducing information on/from an optical disc, wherein the optical disc has a first to an n-th recording layers (n is an integer of 2 or greater) laminated on a substrate, each of the first to the n-th layers having data regions segmented into a first to an m-th data zone groups (m is an integer of 2 or greater) along a radial direction of the optical disc, each of the first to the m-th data zone groups including at least one data zone, the method comprising the steps of: a) recording/reproducing information in/from data zone groups from a j-th data zone group of a first recording layer to a j-th data zone group of an n-th recording layer; and b) repeating step a) for j=1, 2, . . . , m.

Abstract: An optical disc apparatus according to the present invention is usable for an optical disc including a bar code area and a control data area adjacent to the bar code area in a radial direction of the optical disc. The optical disc apparatus includes an optical head for directing an optical beam toward the optical disc so as to form an optical spot on the optical disc and output a signal in accordance with the optical beam reflected by the optical disc; a bar code area determination section for determining whether or not the optical spot is positioned on the bar code area of the optical disc based on the signal output by the optical head; and a control section for controlling the optical head so that the optical spot moves toward the control data area, when the optical spot is determined to be positioned on the bar code area.

Abstract: The optical disc drive reads and/or writes data from/on an optical disc having an information storage layer. In an optical disc drive 100, light from a light source 3 is focused by a focusing section 1, and each of the peripheral and non-peripheral part of light reflected by the information storage layer is received by a photodetector 4. Then, for each part of light, the drive 100 generates a focus signal and a light quantity signal, and normalizes the focus signal based on the light quantity signal. As a result, it is possible to generate a spherical aberration signal according to a quantity of spherical aberration produced at the focusing position of the light. Hence, the signal is not affected by defocusing and thus it is possible to precisely detect a spherical aberration caused by an uneven thickness of the disc and to detect a spherical aberration with high accuracy.

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 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 apparatus includes an optical detector which has light receiving areas divided nearly concentrically with an optical beam and outputs a signal corresponding to the amount of the reflected light from an optical disk. A surface vicinity detecting section adds up signals from all the light-receiving areas of the optical detector and outputs a detection signal. The detection signal continuously varies so as to have one maximum level while a beam spot of the optical beam moves from the surface of the information medium to the information plane. An information plane detecting section judges that the focus or the beam spot of the optical beam comes closer to the information plane of the optical disk by detecting the gradient of the detection signal. An approach of a condensing lens and the optical disk is judged based on the judgment results, and thus a collision of the condensing lens and the optical disk can be prevented.

Abstract: An optical disc apparatus comprises: rotating means for rotating an information recording medium; a light source for irradiating a light beam onto a data side of the information recording medium; converging means for converging said light beam; focus error detecting means for detecting a difference between said data side and the focus of the light beam converged by said converging means; focus direction transferring means for transferring said converging means in a direction perpendicular to said data side; focus controlling means for driving said focus direction transferring means based on the output of said focus error detecting means in such a way that said light beam converges on said data side in a predetermined state; tracking direction transferring means for transferring said light source in the radius direction of said information recording medium; and tilt calculating means for calculating average values of the outputs of said focus controlling means obtained for a period of time, which is an integer

Abstract: An optical disc apparatus according to the present invention is usable for an optical disc including a bar code area and a control data area adjacent to the bar code area in a radial direction of the optical disc. The optical disc apparatus includes an optical head for directing an optical beam toward the optical disc so as to form an optical spot on the optical disc and output a signal in accordance with the optical beam reflected by the optical disc; a bar code area determination section for determining whether or not the optical spot is positioned on the bar code area of the optical disc based on the signal output by the optical head; and a control section for controlling the optical head so that the optical spot moves toward the control data area, when the optical spot is determined to be positioned on the bar code area.

Abstract: An optical disc apparatus according to the present invention is usable for an optical disc including a bar code area and a control data area adjacent to the bar code area in a radial direction of the optical disc. The optical disc apparatus includes an optical head for directing an optical beam toward the optical disc so as to form an optical spot on the optical disc and output a signal in accordance with the optical beam reflected by the optical disc, a bar code area determination section for determining whether or not the optical spot is positioned on the bar code area of the optical disc based on the signal output by the optical head; and a control section for controlling the optical head so that the optical spot moves toward the control data area, when the optical spot is determined to be positioned on the bar code area.

Abstract: The present invention provides a method for recording/reproducing information on/from an optical disc, wherein the optical disc has a first to an n-th recording layers (n is an integer of 2 or greater) laminated on a substrate, each of the first to the n-th layers having data regions segmented into a first to an m-th data zone groups (m is an integer of 2 or greater) along a radial direction of the optical disc, each of the first to the m-th data zone groups including at least one data zone, the method comprising the steps of: a) recording/reproducing information in/from data zone groups from a j-th data zone group of a first recording layer to a j-th data zone group of an n-th recording layer; and b) repeating step a) for j=1, 2, . . . , m.

Abstract: An optical disc drive includes an optical system, a photodetector, a filter, a phase difference detecting section, a signal generating section, and a control section. The optical system focuses a light beam on an optical disc loaded. The photodetector includes areas to receive the light beam reflected from the disc and generates read signals representing quantities of light received. The filter receives the read signals and outputs processed signals with a frequency component of the read signals attenuated according to mark lengths. The phase difference detecting section detects a phase difference between the processed signals. The signal generating section generates a tracking error signal, representing a positional relationship between the focal point and a target track, based on the phase difference. The control section generates a control signal based on the tracking error signal such that the focal point is controlled across the tracks on the disc.

Abstract: The optical disc drive reads and/or writes data from/on an optical disc having an information storage layer. In an optical disc drive 100, light from a light source 3 is focused by a focusing section 1, and each of the peripheral and non-peripheral part of light reflected by the information storage layer is received by a photodetector 4. Then, for each part of light, the drive 100 generates a focus signal and a light quantity signal, and normalizes the focus signal based on the light quantity signal. As a result, it is possible to generate a spherical aberration signal according to a quantity of spherical aberration produced at the focusing position of the light. Hence, the signal is not affected by defocusing and thus it is possible to precisely detect a spherical aberration caused by an uneven thickness of the disc and to detect a spherical aberration with high accuracy.

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 disc apparatus comprises: rotating means for rotating an information recording medium; a light source for irradiating a light beam onto a data side of the information recording medium; converging means for converging said light beam; focus error detecting means for detecting a difference between said data side and the focus of the light beam converged by said converging means; focus direction transferring means for transferring said converging means in a direction perpendicular to said data side; focus controlling means for driving said focus direction transferring means based on the output of said focus error detecting means in such a way that said light beam converges on said data side in a predetermined state; tracking direction transferring means for transferring said light source in the radius direction of said information recording medium; and tilt calculating means for calculating average values of the outputs of said focus controlling means obtained for a period of time, which is an integer

Abstract: An optical disk apparatus includes an optical detector which has light receiving areas divided nearly concentrically with an optical beam and outputs a signal corresponding to the amount of the reflected light from an optical disk. A surface vicinity detecting section adds up signals from all the light-receiving areas of the optical detector and outputs a detection signal. The detection signal continuously varies so as to have one maximum level while a beam spot of the optical beam moves from the surface of the information medium to the information plane. An information plane detecting section judges that the focus or the beam spot of the optical beam comes closer to the information plane of the optical disk by detecting the gradient of the detection signal. An approach of a condensing lens and the optical disk is judged based on the judgment results, and thus a collision of the condensing lens and the optical disk can be prevented.

Abstract: An optical disc apparatus according to the present invention is usable for an optical disc including a bar code area and a control data area adjacent to the bar code area in a radial direction of the optical disc. The optical disc apparatus includes an optical head for directing an optical beam toward the optical disc so as to form an optical spot on the optical disc and output a signal in accordance with the optical beam reflected by the optical disc, a bar code area determination section for determining whether or not the optical spot is positioned on the bar code area of the optical disc based on the signal output by the optical head; and a control section for controlling the optical head so that the optical spot moves toward the control data area, when the optical spot is determined to be positioned on the bar code area.