Abstract: A recording medium includes: at least one recording layer on which information is recorded by multi-photon absorption; and a servo layer disposed in a laminated direction with respect to the recording layer and having a track for guiding a beam spot of laser light having a first wavelength and a beam spot of laser light having a second wavelength along a scanning trajectory, wherein the servo layer and the at least one recording layer constitute a set of layers, and a plurality of sets of layers is formed in the laminated direction.

Abstract: An optical recording medium driving apparatus includes an optical pickup which irradiates first and second laser lights from one object lens with respect to an optical recording medium having a bulk layer and a tilt detection surface; a focus control portion that performs the focus control relative to each predetermined position of the optical recording medium in regard to each of the first and second laser lights; a tracking control portion that controls the position of the object lens to perform the tracking control of the first and second laser lights relative to the optical recording medium; and a tilt control portion.

Abstract: An optical information medium measurement method measures a degree of modulation in an optical information medium of a multilayered structure having a plurality of information layers. The method includes measuring the modulation degree of each layer of the optical information medium, obtaining a thickness between layers of the optical information medium, obtaining a reflectance of each layer of the optical information medium, and converting the modulation degree of each layer. The modulation degree is measured based on a value indicative of the thickness between layers, and a value indicative of the reflectance of each layer.

Abstract: A reproduction apparatus for an optical recording medium that has a convex pit recording layer, in which pits are formed in a convex shape viewed from a laser incidence side, and a concave pit recording layer, in which pits are formed in a concave shape viewed from the laser incidence side, as recording layers in which data is recorded by pit strings, the pits being formed with a depth that is set in a range of ?/4.5 to ?/6 with respect to a laser wavelength ?, including: an optical head section that irradiates laser beams on the recording layers and detects reflected light information to read out information recorded in the recording layers; a tracking error signal generating section that generates a tracking signal; a polarity switching section that switches a polarity of the tracking error signal; and a tracking servo section that performs a tracking servo operation.

Abstract: Disclosed is an adjustment apparatus for adjusting an optical pickup capable of recording and/or reproducing plural optical discs of different sorts. The adjustment apparatus is an optical disc for adjustment (1) having a first signal recording layer (5) having a physical format in common with a CD and a second signal recording layer (7) having a physical format in common with a DVD. On the first and second signal recording layers, there are concentrically recorded EFM modulated data. The respective signal recording layers are provided with recording areas (8), (9) not overlapped with each other.

Abstract: An optical information medium measurement method, for measuring a degree of modulation in an optical information medium of a multilayered structure having a plurality of information layers, includes a first step of measuring a modulation degree of each layer of the optical information medium, and a second step of obtaining a thickness between layers of the optical information medium. Further, the method includes a third step of obtaining a reflectance of each layer of the optical information medium, and a fourth step of converting the modulation degree of each layer, as measured in the first step, into a modulation degree at a reference optical system differing from the measurement optical system, based on a value indicative of the thickness between layers, the thickness being obtained in the second step, and a value indicative of the reflectance of each layer, as obtained in the third step.

Abstract: Minimized is the influence which is exerted by recording calibration (test recording) such as power calibration, strategy calibration or the like, performed in an area for recording calibration (recording calibration area or test area) provided in each of a plurality of recording layers, on recording calibration performed in the other recording layers. On a recording medium, data is recorded on at least one of a plurality of recording layers by laser light incident on a surface of the recording medium. The plurality of recording layers include a first recording layer, and second through N-th recording layers (N is an integer of 3 or greater) which are sequentially located in a direction from the first recording layer toward the surface on which the laser is incident. The plurality of recording layers each have a first calibration area and a second calibration area located outer to the first calibration area.

Abstract: An optical recording medium including recording and reading layers and a servo layer increases the recording capacity thereof. In the optical recording medium including the plurality of recording and reading layers and the servo layer, the servo layer has a groove and a land that can be used to perform tracking control with a long-wavelength servo beam. Information is recorded on the recording and reading layers with a recording and reading beam having a wavelength shorter than the wavelength of the servo beam. Recording marks are formed on the recording and reading layers while both the groove and land are tracked.

Abstract: A recording apparatus performs recording on an optical disc recording medium which has a plurality of recording layers and is capable of having data rewritten thereon. The recording apparatus includes recording means for performing data recording on each recording layer of the recording medium and recording controlling means for controlling the recording means so that, among the plurality of recording layers, recording of dummy data is performed preferentially starting from a recording layer intended for the final user data recording operation.

Abstract: A recording apparatus for performing information recording using formation of marks by focusing a first light with an objective lens at a given position in a recording layer included in an optical disc recording medium, includes: a rotation driving unit; a focus servo control unit for condensing a second light on a reflection film and for controlling a position of the objective lens; a recording position setting unit for setting an information recording position of the first light in a focus direction; a tracking servo control unit for controlling a position of the objective lens; an eccentricity amount estimating unit for estimating an eccentricity amount of the optical disc recording medium; and an eccentricity estimation amount acquisition control unit for acquiring an eccentricity estimation amount for each rotation angle within one revolution of the disc.

Abstract: A deterioration of reproduction light is occurred by a laser drive current on which a high-frequency current is superimposed. The present invention, for example, is an optical information reproducing apparatus which irradiates a laser beam to an optical disc 1 and reads an information, the optical information reproducing apparatus includes a semiconductor laser 6 which generates the laser beam, a laser drive unit 7 which supplies a drive current on which a high-frequency current are superimposed to the semiconductor laser 6, a spindle motor 2 which drives the optical disc 1 and a control unit 5 which controls the laser drive unit 7 and the spindle motor 2, and the control unit 5 determines a parameter of the high-frequency current based on magnitude of a current on which the high-frequency current is to be superimposed.

Abstract: An optical disc apparatus capable of deriving optimum laser beam power even when OPC areas overlap with one another and a method for the apparatus. OPC result is recorded to an optical disc and OPC (area-saving OPC) that reduces an area use quantity by using the OPC result is executed and optimum laser power is determined.

Abstract: An optical pickup apparatus is provided with an optical system for guiding a laser light emitted from a laser light source to an objective lens and also for guiding the laser light reflected by a recording medium to a photodetecting section as a convergent light. The photodetecting section is provided with first and second photodetectors disposed at positions at which a first part of the target laser light and a second part different from the first part are respectively received, the positions being separated further from the optical system than a convergence position of a target laser light reflected by an irradiation-target recording layer, out of the laser light reflected by the recording medium, and a third photodetector disposed at a position closer to the optical system than the convergence position of the target laser light, the position being bridging more over the second part than the first part.

Abstract: A multi-layer data storage medium includes a plurality of recording layers in which a guide groove, where data is stored, is formed in a spiral manner, and each center of the plurality of the recording layers is eccentric to a center of the multi-layer data storage medium in a different direction. A method of identifying a recording layer of the multi-layer data storage medium is also described.

Abstract: When a laser light focal point, driven by an objective lens, passes through each of a plurality of recording layers of an optical disc, data recorded on the recording layers through which the focal point passes may be deteriorated due to a difference in optical sensitivity for each recording layer or the like. In a focal point position movement in which switching of recording layers is made by a focus error signal, when the focal point position moves from a recording layer on which a laser light is focused to another recording layer which is not adjacent, light intensity or light density at the focal point is reduced in accordance with the recording layer to be passed through, thus deterioration of the data on the optical disc being prevented.

Abstract: An optical disc device is provided with an optical head including a light source, a condensing optical system including an objective lens for receiving a light beam emitted from the light source and forming a microspot on a multilayer optical recording medium, a photodetector for receiving the light beam reflected by the multilayer optical recording medium and outputting an electrical signal corresponding to the amount of light and a coma aberration correcting element for correcting a coma aberration of the condensing optical system, and a processing circuit for controlling the condensing optical system and the coma aberration correcting element.

Abstract: A disc-shaped information recording medium includes a first recording layer (L0 layer) having (I) a first trial write area (101P-1) for trial write of first trial write information for calibration of the laser beam along the first track path (TP1) from the inner circumference toward the outer circumference and (II) a first recording area for recording the first recording information along a first track path (TP1), in this order from the inner circumference side. Furthermore, the disc-shaped information recording medium includes a second recording layer (L1 layer) having (I) a second trial write area (101P-2) for trial write of second trial write information for calibration of the laser beam along the second track path (TP2) from the outer circumference toward the inner circumference and (II) a second recording area for recording the second recording information along a second track path (TP2), in this order from the inner circumference side.

Abstract: An optical disc drive for reading or writing information on a multilayer optical disc having three or more recording layers by irradiating the disc with a light beam includes an optical pickup for irradiating the disc with the light beam, a recording state detector for detecting data recording states at a start point of a focus jump, a transit point or transit points on a recording layer or recording layers to be passed through, and an expected landing point of a focal point of the light beam in a focus jump, and a controller for moving the optical pickup to a position where the recording states are the same at all of the start point, the transit point(s) on the recording layer(s) to be passed through, and the expected landing point if the recording states are different among those points, before starting the focus jump.

Abstract: A disclosed multilayer optical information medium includes three or more information layers. Address information indicating positions in each of the information layers is recorded in a helical manner. The information layers comprise at least one I to O layer in which values representing addresses in the address information increase from an inner perimeter section toward an outer perimeter section, and at least one O to I layer in which the values representing the addresses in the address information increase from the outer perimeter section toward the inner perimeter section. All of the I to O layers have substantially the same address information and all of the O to I layers have substantially the same address information. Layer specifying information specifying the information layer is attached to the address information.

Abstract: Disclosed herein are an optical recording medium driving device and an additional recording method, which performs tracking servo control for moving an objective lens in a direction orthogonal to a tangential direction of a guide track so that a guide tracking error signal is decreased with respect to a guide track of a guide layer separation type recording medium, detects an additional recording start position subsequent to a recorded track if the recorded track is present in a recording layer of the optical recording medium, generates a tracking correction signal according to the reproduction tracking error signal upon tracking servo control of the recorded track just before the additional recording start position, and corrects tracking servo control according to the tracking correction signal upon additional recording start.

Abstract: Shape-wise thicknesses of a cover layer and first through (N?1)th intermediate layers of an optical recording medium having refractive indexes nr1, nr2 are converted into thicknesses t1, t2 of the respective layers having a predetermined refractive index which makes a divergent amount equal to a divergent amount of a light beam resulting from the thicknesses tr1, tr2, a difference DFF between the sum of a thickness “ti” through a thickness “tj”, and the sum of a thickness “tk” through a thickness “tm” is set to 1 ?m or more (where i, j, k, and m are each any positive integer satisfying i?j?k?m?N), and the thicknesses t1, t2 are calculated by products of a function f(n) expressed by the following formula (1), and the thicknesses tr1, tr2: f(n)=?1.088n3+6.1027n2?12.042n+9.1007??(1) in the formula (1), n=nr1, nr2, . . . , and nrN.

Abstract: A method is disclosed of reading an image data from an optical record carrier with a visually detectable pattern comprising a visually detectable pattern of pixels comprising at least one pattern element comprising an area of size s1 with a relatively low value v1 for an optical property and an area with size s2 with a relatively high value v2 for said optical property, wherein the data representative for a structure of the visually detectable pattern is embedded by variations in one or more of the parameters s1, v1, s2, v2 of the pattern elements. The method comprising the steps of scanning the visually detectable pattern and generating a detection signal representative for a visual property of the pattern as a function of position, retrieving the image data from the signal, retrieving an embedded data from the signal, generating an address data using said embedded data, storing image data values at addresses indicated by said address data.

Abstract: In recording or reproducing data on or from an optical disc with recording multi-layers, the focusing is likely to be out of control when an inter-layer jumping is carried out for changing a recording layer on or from which data is to be recorded or reproduced to another one. An optical disc apparatus is arranged to obtain an objective lens shift position that makes the focus signal S-character waveform better balanced in advance by learning and to carry out the inter-layer jumping at the shift position when jumping an optical pickup from one layer to another on a multilayered optical disc. The jumping at this shift position makes it possible to prevent out of focus and to stably make the recording or reproducing quality excellent.

Abstract: A recording device comprises a recording means (213, 214) for recording content data on a recordable recording medium (100) having a first recording layer (110) including a first data area (112) and a second recording layer (120) including a second data area (122), a first reading means (213, 214) for reading the address of the position corresponding to the maximum capacity of the first data area, a second reading means (221) for reading the address of the layer jump position of the content data, a calculating means for calculating the position at which the recording of the contents data is started such that the layer jump position of the content data is recorded at the position corresponding to the maximum capacity of the first data area, and a first controlling means (221); for controlling the recording means such that first padding data is recorded in an area from the start position of the first data area to the position at which the recording of the contents data is started.

Abstract: An optical system for optical pickup, which optical system is used for performing recording, reproducing, and/or erasing of information on an optical recording medium and has a simple configuration, is provided. An optical pickup device 1 includes a collimator lens system 23, a beam expander 33, and an objective lens system 34 that includes an S-SIL element 27b. The beam expander 33 includes three lens elements 33a to 33c. By moving in an optical axis direction, the two lens elements 33a and 33b included in the beam expander 33 adjust a focal point of a spot formed within an optical recording medium 28, and compensate a spherical aberration caused by the difference in depth between recording layers.

Abstract: There is a need to accurately lock focus of a laser beam onto a target data layer of a multilayer optical disc. The above need can be addressed by, for example, performing a focus lock operation after a spherical aberration correction amount is set in such a way as to make smaller the ratio of the focus error signal waveform amplitude at the data layer adjacent to a target data layer through which a laser beam passes earlier than through the target data layer to the focus error signal waveform amplitude at the target data layer than that when the spherical aberration correction amount is set so as to be optimal for the target data layer.

Abstract: A light source unit comprises a plurality of light sources emitting a plurality of light beams. A plurality of volume hologram elements are provided for the plurality of light sources respectively, each volume hologram element having a plane of incidence of an incoming light beam and a plane of outgoing radiation of a diffracted light beam which are perpendicular to each other, the plurality of volume hologram elements having mutually different Bragg conditions in which an optical intensity of a diffracted light beam is set to a maximum.

Abstract: An optical disc apparatus for use of an optical disc including a plurality of recording layers sets an amount of correction of spherical aberration for each of the recording layers of the disc during a focus sweep. A photodetector portion produces a signal in response to returned light for each of the recording layers.

Abstract: An optical disc device includes a laser diode which irradiates an optical disc having a plurality of layers with laser light, a photodetection section which detects laser light reflected by the optical disc, which comprising a pair of sub-photodetectors and a main photodetector provided between the pair of sub-photodetectors, a focus error signal generation circuit which generates a focus error signal from a photodetection signal output by the main photodetector, a tracking error generation circuit which generates a tracking error signal from the photodetection signal output by the main photodetector and a photodetection signal output by the pair of sub-photodetectors, and a layer determination signal processing circuit which generates a layer determination signal from the photodetection signal output by the pair of sub-photodetectors and determines in which of the layers a focus of the laser light is located, on the basis of the layer determination signal and focus error signal.

Abstract: Prevention of deletion of data in an unintended recording layer of an optical disc is ensured even when servo deviation occurs while controlling data reproduction. A light source outputs a light beam with light intensity according to a driving current on which a high frequency signal is superimposed. The light beam is collected on a recording layer of an optical disc. As triggered by detection of servo deviation during data reproduction, a light intensity controller adjusts a superimposed amount of the high frequency signal in the driving current to suit to a specific recording layer with the lowest reproduction tolerance in the optical disc and thereby controls the light intensity of the light beam output from the light source.

Abstract: An optical disc apparatus including means for calculating a spherical aberration correction quantity of an object lens, reproduced information signal generation means and spherical aberration correction means conducts spherical aberration correction, finds a spherical aberration correction quantity suitable for another layer by calculation on the basis of the obtained spherical aberration correction quantity, and sets the correction quantity as an initial correction quantity of spherical aberration correction. An optical disc apparatus including tilt correction quantity calculation means, reproduced information signal generation means and tilt adjustment means conducts tilt adjustment, finds a tilt correction quantity suitable for another layer by calculation on the basis of the obtained tilt correction quantity, and sets the correction quantity as an initial correction quantity of tilt adjustment.

Abstract: The present invention provides an optical disk apparatus and a focus jump method capable of reliably performing a focus jump by appropriately obtaining the amplitude of a signal such as a focus error signal in a multilayer optical disk. An optical disk includes jump areas which are provided separately from data areas and at which a focus jump is performed. When a focus jump is performed, an optical pickup is moved to the jump area, and the laser power level of the optical pickup is changed and set in accordance with a target layer to which the focus is jumped. A focus position is allowed to reach the target layer by counting the number of times of intersecting with recording layers using a reflected light from the optical disk while performing a focus sweep of an objective lens in the optical pickup.

Abstract: The present invention is related to a method and a reading device (1) for retrieving information from an optical record carrier (10) in which the read power level of a radiation beam (3) for scanning the optical record carrier is set in dependence on the read-out speed. The invention is also related to a record carrier for use with such a method and a reading device.

Abstract: A combination type optical disk medium and recording or reproducing method in which the medium include first and second recording layers based on different recoding densities. First and second volume spaces are formed to the first and second recording layers, respectively. Each volume space includes identification information of a head or end of the volume space, and an area for data. One of the volume spaces is recorded with identification information of the other volume space.

Abstract: A method of determining a disk type of an optical disk is provided to comprise steps of: using a first light path for forming an incident beam; moving an objective lens system corresponding to the first light path from a start position towards the optical disk; receiving a sensor output signal during the movement of the objective lens system, wherein the sensor output signal includes a central aperture signal; determining the disk type of the optical disk according to the central aperture signal.

Abstract: An optical recording medium having a read-only storage area and a writable storage area and a recording/reproducing apparatus and method therefor. The optical recording medium is a hybrid disc having both the read-only storage area, which is suitable for mass production of information having the same contents, and the writable storage area on which data can be recorded, updated or added at a user's option.

Abstract: In response to the trend toward the increase in the number of data layers of optical discs, the invention provides a data erasure method and its optical disc apparatus that enable faster data erasures with a simpler configuration. Test erasures are performed on the test areas T of data layers of an optical disc while the power level Pe of data erasure laser light and the defocus amount ?f of the data erasure laser light from a target data layer are changed. Based on the results of the test erasures, the optimal erasure condition that enables a simultaneous data erasure from the greatest number of data layers is determined. Based on the determined optimal erasure condition, then, the optimal erasure sequence that enables data erasure from all of the data layers with the fewest number of times is determined.

Abstract: The present invention relates to a recording apparatus, a recording method, a program, and a recording medium whereby data is reproduced from a two-layer optical disk that has yet to be formatted completely. A control section 51 divides a recording area of a layer L0 of the optical disk 33 into a plurality of recording regions and a recording area of a layer L1 of the same disk 33 into a plurality of recording regions at substantially the same physical positions as the recording regions of the layer L0. A control section 51 records the region where user-designated data was last written. The control section 51 controls a signal processing section 56 to write dummy data to the recording area of the layer L0 or L1 different from the layer that includes the region to which the user-designated data was last written.

Abstract: An optical disc apparatus according to the present invention includes a disc type recognizing section for determining whether the optical disc loaded is a first type, of which the number of information storage layers is less than a setting T (where T is an integer that is greater than two), or a second type, of which the number of information storage layers is equal to or greater than the setting T. Depending on whether the optical disc loaded has turned out to be the first type or the second type, the apparatus determines the read/write preprocessing (such as whether a fingerprint detection process needs to be performed or not).

Abstract: Each layer includes a data recording area and a test writing area divided into a plurality of small areas, wherein the small areas of the test writing area are recorded in advance so that other each layer can make a combination of recorded and unrecorded states with respect to the small area, where OPC is carried out, in a layer where OPC is carried out. Moreover, OPC is carried out to each small area, where a combination of recorded/unrecorded states of other each layer differs from each other, to thereby calculate, as the optimum power, an average value of the result of each OPC or a central value of the dispersion thereof.

Abstract: A multilayer recording medium has a three-layered structure for an increased capacity, including an L0 layer, an L1 layer, and an L2 layer in order from the side farthest away from the incident surface of laser light. The recording layers are made of respective recording film materials selected so that the recording films of the recording layers have respective recording-reaction temperatures T0, T1, and T2, where T0?T1?T2 and T0<T2. This makes the recording sensitivities of the respective recording layers substantially the same and, by extension, the optimal recording powers of the laser light for the respective recording layers substantially the same so that the recording power of the laser light necessary for recording information on the L0 layer in particular is prevented from becoming excessively high.

Abstract: An information recording medium according to the present invention includes at least three information recording layers. If the readout power of a laser beam in reading information from an information recording layer L(n) is identified by Pw(n), and if the readout power of the laser beam in reading information from an information recording layer L(n+a) is identified by Pw(n+a), then a base thickness between the information recording layers is determined so that the intensity of the light when the information recording layer L(n+a) is irradiated with a laser beam having the readout power Pw(n) becomes equal to or lower than that of the light when the information recording layer L(n+a) is irradiated with a laser beam having the readout power Pw(n+a).

Abstract: A multilayer optical disc has dimples and/or bumps on a surface of at least one of the layers. Dimensions of the dimples and/or bumps, such as size, frequency and pitch, are selected to generate frequency components in light reflected from the surface that are different from frequency of servo and/or information signals. A disc drive can then use an appropriate filter to remove signals produced by light reflections of an unintended layer.

Abstract: An optical disc apparatus includes an optical pickup for outputting an output signal according to reflected light from an optical disc medium and a comparison signal output unit for outputting a comparison signal indicating whether a level of the output signal is higher than a threshold value, relatively moves an objective lens with respect to a surface of the medium within a predetermined range to measure a maximum level of the output signal, sets a value determined according to the maximum level as a threshold value used by the comparison signal output unit, and measures a level of a reflected signal corresponding to reflected light from each of a plurality of signal surfaces based on the output signal in a time period in which the comparison signal indicates that the level of the output signal is higher than the set threshold value, while moving the objective lens.

Abstract: An apparatus includes a recorder having at least two optical pickup heads for simultaneously recording at least two bit streams on respective layers of recordable media in one of an opposite track path and a parallel track path.

Abstract: A recording method for recording data in basic reproduction unit to a recording medium having a first recording layer and a second recording layer, includes detecting a size of an unrecorded region of the first recording layer while recording data in the basic reproduction unit in the first recording layer, comparing the size of the unrecorded region of the first recording layer with a specified value and stopping recording in the first recording layer at the boundary of the basic reproduction unit when the size of the unrecorded region is smaller than the specified value, and recording a subsequent data in the second recording layer.

Abstract: This optical disk device includes a pickup, an offsetting means, a focus servo means, a layer jump means, and a shift means. The pickup irradiates laser light upon an optical disk having a plurality of recording layers via a correction lens and an objective lens, and detects light reflected back from the optical disk. The offsetting means generates a focus error (FE) signal on the basis of the reflected light, and applies an offset voltage to the focus error signal. The focus servo means performs focusing servo on the basis of the FE signal. And, before layer jumping is executed by the layer jump means, the focus servo means displaces the correction lens to an intermediate position after having adjusted the offset voltage to a balance value. Then the layer jump means performs layer jumping.

Abstract: A recordable dual-layer optical disc which allows precise recording learning on both layers. A first information recording layer located further from the light incidence side includes a read-only control data area, a first test area, and a second test area. A second information layer located closer to the light incidence side includes a third test area located at a position opposite to the control data area, and a fourth test area located at a position opposite to the second test area.

Abstract: An information recording apparatus (200) is provided with: a recording device (353) for recording data onto an information recording medium (100) being provided with a first recording layer (L0) and a second recording layer (L1); a first controlling device (354) for controlling the recording device to record the data into each of the first recording layer and the second recording layer; a forming device (354) for forming a compatibility area (106, 109, 116, 119) for realizing reproduction compatibility of the information recording medium on an information recording apparatus, following the data recorded in each of the first recording layer and the second recording layer; and a second controlling device (354) for controlling the recording device to record the data into the formed compatibility area if the data is recorded after the compatibility area is formed.

Abstract: Disclosed herein is a recording medium on or from which the recording or reproduction of data is stably performed. On the recording medium, data are recorded three-dimensionally by the irradiation of a recording laser beam. The recording medium includes a reflection control layer including a plurality of reflection layers stacked in a film thickness direction, each reflection layer having a connection terminal, each reflection layer exhibiting reflectivity and transmissivity changeable in response to an electrical signal supplied to the connection terminal and a recording layer disposed at a beam incidence side of the reflection control layer.