Abstract: An information recording medium (100) is provided with a plurality of recording layers (L0 layer, L1 layer) to record therein record information, and property information (200) indicating properties of the each recording layer is recorded in each of the plurality of recording layers.

Abstract: An optical recording medium wherein a laser beam at a wavelength ? is irradiated and recording and reproducing of information are performed by optical power modulation of binary or more, and when the refraction index of the first substrate being n1, the refraction index of the intermediate layer being n2, the groove depth, the groove width and the track pitch of the first information layer being d1, w1 and p1 respectively and the groove depth, the groove width and the track pitch of the second information layer being d2, w2 and p2 respectively, the following conditions are satisfied. 4?/16n1?d1?7?/16n1 ?/16n2?d2?3?/16n2 or 4?/16n2?d2?7?/16n2 0.2?w1/p1?0.55 0.2?w2/p2?0.

Abstract: To provide an optical disk and an optical disk reproducing device capable of preventing sub information from being illegally copied and altered. An optical disk includes an optical disk substrate preliminarily provided with concave/convex recording marks in order to record the main information; and a reflection film which covers the optical disk substrate and of which the reflection coefficient is changed by irradiating laser light at or above a certain intensity. The reflection film is preliminarily provided with additional marks for recording the sub information by changing the reflection coefficient of the reflection film on a region where the concave/convex recording marks are formed and the sub information is recorded for every predetermined recording unit for recording the main information. The laser light at or above the certain intensity is irradiated onto the region where the sub information is recorded to reproduce the main information and delete the sub information.

Abstract: An information recording medium includes a substrate and an information layer formed on the substrate. The information layer includes a recording layer whose phase can be changed between a crystalline phase and an amorphous phase by irradiation with a laser beam or application of electric energy; a Cr-containing layer including at least Cr and O, arranged in contact with a first surface of the recording layer; and a Ga-containing layer including at least Ga and O, arranged in contact with a second surface of the recording layer.

Abstract: An information recording medium according to the present invention includes a track on which a data sequence including a plurality of recording marks and a plurality of spaces provided between the plurality of recording marks is recordable; and a recording condition recording area in which a recording condition for recording the data sequence on the track is recordable.

Abstract: A method to erase data stored on an erasable optical recording system is provided. The optical recording system includes a laser IO head having a blue-light laser, a red-light laser, and an infrared-light laser writing data on the blu-ray disc, the DVD disc, and CD disc, respectively. The method includes indexing the infrared-light laser of the laser IO head one track of the blu-ray disc every 0.4 revolutions after first 0.8 revolutions, to erase the data stored on the blu-ray disc.

Abstract: Because conditions for recording identification data of a medium vary in accordance with the structure of different media, such as a single-layer or a multiple-layer structure, stable data recording has been a difficult task. To solve this problem, an incident side of the laser beam for recording identification data on a single-layer optical disk 5 and a double-layer optical disk 6 is the opposite side of a substrate 1 upon which user data is recorded. From this structure, even in a double-layer optical disk 6, the recording is not affected by the recording layer of a second layer 12b and the like. Therefore, in the double-layer optical disk 6, identification data of the medium can be recorded under the same conditions as the single-layer optical disk 5.

Abstract: An optical recording medium has a five-layer structure including five recording layers, namely an L0 layer, an L1 layer, an L2 layer, an L3 layer, and an L4 layer in this order from a side farthest away from a laser light incident surface. The materials of the respective recording layers are selected so that the rate of change in transmittance Tb/Ta as taken from the laser light incident surface satisfies 0.93<Tb/Ta<1.07 when recording on the L0 layer among the recording layers, where: Ta is transmittance of laser light to reach the L0 layer when the L0 layer is irradiated with the laser light of optimum recording power after recording marks are formed on all the recording layers closer to the laser light incident surface (being the L1 to L4 layers); and Tb is transmittance of laser light to reach the L0 layer when the L0 layer is irradiated with the laser light of optimum recording power with no recording mark formed on any of the recording layers closer to the laser light incident surface.

Abstract: An optical disc medium (10) is provided with a data recording area (12) having the spiral recording track (11) and a lead-in area (13) composed of an embossed pit. In the lead-in area (13), information indicating a characteristic range of a signal detected by an optical head from a groove track is previously recorded. In accordance with a kind of the optical disc medium (10), even when the characteristic range of the signal detected by the optical head from the groove track is different, since the information indicating the characteristic range is previously recorded on the optical recording medium (10), tracking operation of the recording track can be performed under conditions within the characteristic range. Therefore, the tracking operation of the recording track (11) can be accurately performed to any kind of optical disc medium (10).

Abstract: The invention provides for modifications to conventional optical data storage media to reduce the amount of raw material necessary in the media construction. More particularly, a portion of a thermoplastic substrate is modified to create one or more substantial void areas compared to a conventional substrate that defines flat parallel surfaces without void areas. The configuration, number, and size of the voids may be modified in order to substantially reduce inherent raw material cost while maintaining the specified physical thickness, clamping area, and mechanical stability of the medium.

Abstract: Provided are a method and a device for permanently erasing data of an optical disk in an optical disk drive including an optical disk emulation. According to the method, an erase command of data recorded on an optical disk is received and it is determined whether the optical disk is a rewritable optical disk or not. Then, an output power of a laser to be projected is raised when the optical disk is the rewritable optical disk and then the data recorded on the optical disk are erased through an output power of the laser. Furthermore, the optical disk drive includes an optical disk storage unit, a contents memory unit, a disk type determination unit, a laser power adjustor, a pick-up unit, and a controller.

Abstract: An optical disk includes a groove and a land. Data is recorded on either the land or the groove. A pitch of the groove and a pitch of the land are 0.32 ?m or more. The optical disk has a data efficiency of 80% or more by adopting a format in which other types of user data are added to every plural user data sets. The data efficiency is defined by a ratio of a user data capacity that can be used by a user to a total data capacity of the optical disk.

Abstract: An optical-information recording medium includes a substrate that includes a servo surface having a servo pattern thereon; an information recording layer laminated on the servo surface of the substrate capable of recording information as a hologram produced by interference between an information beam containing the information and a reference beam; an address servo area that is formed as a part of the servo pattern, and that records therein address information and clock information for aligning a beam, emitted from an optical-information recording apparatus for recording information in the information recording layer, to a target position in the information recording layer; and a following up servo area that is formed as a part of the servo pattern, and that is to be irradiated by the beam to make the beam follow a rotation of the optical-information recording medium.

Abstract: A multilayer record carrier of a writable type has a first recording layer (40) having a first recording stack (50,51) of a first type and a second recording layer (41) having a second recording stack (54,55) of a second type. The first and second recording stacks have different writing parameters. Each recording layer has a pre-formed recording control pattern that is readable via a laser beam for indicating the track. At least one recording control pattern comprises a recording stack type indicator for indicating the writing parameters of the second recording stack. A recording device has a control unit (20) for adjusting recording parameters in the device in dependence of the recording stack type indicator retrieved from the recording control pattern.

Abstract: A rewritable phase-change optical recording medium is provided, which includes a substrate, a first information layer, a spacer layer, a second information layer, and a cover layer. The second information layer includes a recording film containing Sb as a main component and V or V and In as second components. When an amorphous mark formed in the recording film is irradiated with a reproduction beam, crystallization of the amorphous mark occurs only in a central portion in the width direction of the amorphous mark. The width direction is orthogonal to the scanning direction of the laser beam. The recording film is formed of a material that exhibits a change in degree of modulation of 5% or less when recorded information is repeatedly reproduced. The change in degree of modulation is a change from when the number of times of reproduction is 100,000 to when it is 400,000.

Abstract: Plural grooves or lands formed in an information recording carrier include at least a wobbling region and data is recorded wobblingly in this wobbling region by phase shift modulation while recorded digitally with a single or multiple waves as a channel bit.

Abstract: An information storage medium and a recording/reproducing apparatus and method are provided with the ability to extend at least one middle area of an information storage medium comprising two or more recording layers so as to ensure optimal data recording/reproduction. The information storage medium comprises a plurality of recording layers, each including a user data area for recording user data and at least one middle area used by a recording/reproducing apparatus that records/reproduces data on the information storage medium to move among two recording layers, wherein the at least one middle area is extended when the information storage medium is finalized. As a result, when an information storage medium that contains an OPC area for obtaining optimum recording conditions (such as recording power) in an outer circumference thereof is finalized, and if a middle area of the disk is not large enough, the middle area can flexibly be extended.

Abstract: A substrate in which a minute ruggedness structure including columnar projections is formed in a track shape is prepared. The pitch of the columnar projections of the ruggedness structure is set such that a plurality of the columnar projections is within a beam spot. A flat portion is disposed between adjacent tracks. A reflecting layer is formed on the substrate. The flat portion becomes a mirror surface because of the formation of the reflecting layer. The reflectance of the ruggedness structure becomes significantly lower than the reflectance of the flat portion. When the ruggedness structure is irradiated with high-power laser light, a portion of the ruggedness structure is raised to a reflecting layer side and flattened. At this time, reflectance of the raised portion becomes higher than reflectance of a non-raised portion. When a track including the ruggedness structure is irradiated with high-power pulse laser light, signal recording based on a change in reflectance is possible.

Abstract: An optical record carrier (30) comprising a plurality of information layers formed above a first surface of a substrate wherein at least one of the information layers is a re-writable cache layer is disclosed. The data that is read more than once is copied on to the re-writable cache layer when the recording/reproducing device is not in active use. Next time when the same data is requested, it can be read from the re-writable cache layer. This is advantageous since the data is stored un-fragmented on the re-writable cache layer and the re-writable cache layer can have higher read speeds than the other information layers in the optical record carrier. Therefore, the re-writable cache layer can improve the system performance in terms of read speed.

Abstract: An optical disk includes a recording surface on which a plurality of pits, corresponding to multilevel (three level or higher) information, is formed as a spiral or concentric pit array. The pit array wobbles periodically. A plurality of predetermined reference marks, corresponding to a period of the wobble, are included in the pit array.

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: A multi-layer record carrier is for recording information by writing marks in a track. The record carrier has a first recording layer (40) and a second recording layer (41), and each recording layer has a pregroove (14) indicating the position of the track according to an opposite track path. The pregroove exhibits a modulated wobble for representing control information. A lead-in part of the pregroove has first control information for the first recording layer, and the lead-out part on the second recording layer has second control information including recording parameters for the second recording layer. The device the device has a head (22) for providing the beam and wobble detection means (32) for retrieving control information from each layer.

Abstract: A recording/playback device includes an information conversion unit converting video or audio information, received from an external source, to video or audio data for recording on a rewritable optical disk, a recording unit recording the video or audio data on said optical disk, and a playback unit playing back the video or audio data recorded on said optical disk, in which the optical disk has at least two recording layers and, when the video or audio data is recorded in two or more layers of the optical disk and then a part of the video data or audio data recorded in each layer is erased, a part of the video or audio data left unerased is moved so that a number of layers, in which the video or audio data left unerased is recorded, is reduced.

Abstract: An information recording medium is at least composed of a substrate having a microscopic pattern constituted by a continuous substrate of grooves formed with a groove portion and a land portion alternately, a recording layer formed on the microscopic pattern for recording information, and a light transmitting layer formed on the recording layer. The microscopic pattern is formed with satisfying a relation of P??/NA, wherein P is a pitch of the land portion or the groove portion, ? is a wavelength of reproducing light for reproducing the recording layer, and NA is a numerical aperture of an objective lens. The land portion is formed with wobbling so as to be parallel with each other for both sidewalls of the land portion. An auxiliary information based on data used supplementally when recording the information and a reference clock based on a clock used for controlling a recording speed when recording the information is recorded alternately.

Abstract: A phase-change optical storage medium has a substrate and a recording layer having a plurality of tracks for storing information. A material of which the recording layer is made has been initialized in a crystalline state in which an amplitude of a tracking-detection signal is smaller than a saturation value of the amplitude, the tracking-detection signal being obtained by receiving a reflected beam from the recording layer when the recording layer is irradiated with a laser beam in an off-track state while the optical storage medium is being rotated.

Abstract: A phase-change recording material used for an information recording medium utilizing a crystalline state as a non-recorded state and an amorphous state as a recorded state, which has the composition of the following formula (1) as the main component: (Sb1?xSnx)1?y?w?zGeyTewM1z??formula (1) wherein each of x, y, z and w represents atomicity, x, z and w are numbers which satisfy 0.01?x?0.5, 0?z?0.3 and 0?w?0.1, respectively, and the element M1 is at least one element selected from the group consisting of In, Ga, Pt, Pd, Ag, rare earth elements, Se, N, O, C, Zn, Si, Al, Bi, Ta, W, Nb and V, and (I) when z=0 and w=0, y is a number which satisfies 0.1?y?0.3, (II) when 0?z?0.3 and w=0, y is a number which satisfies 0.05?y?0.3, and (III) when 0?z?0.3 and 0<w?0.1, y is a number which satisfies 0.01?y?0.3.

Abstract: A data storage medium includes a data structure, called a disk control block, used for administration and control information for the data storage medium. One medium may contain multiple different disk control blocks, each addressing a different function. Each disk control block includes a control block identifier that specifies the function of the disk control block. Each control block also includes a set of standard access control parameters. If a drive encounters an unrecognized disk control block, the drive can still decode the standard control parameters, so that the drive behavior is not inconsistent with the requirements of the unrecognized disk control block.

Abstract: Plural grooves or lands formed in an information recording carrier include at least a wobbling region and data is recorded wobblingly in this wobbling region by phase shift modulation while recorded digitally with a single or multiple waves as a channel bit.

Abstract: An optical disc or other optical recording medium enables reading barcode-shaped-BCA marks in a burst cutting area (BCA) with tracking on while making tampering with the BCA marks difficult. The optical disc 100 has a first area 102 containing tracks at a first track pitch d2, and a second area 101 containing tracks at a second track pitch d1. The barcode-shaped marks 104 are recorded in the second area, and the second track pitch is wider than the first track pitch.

Abstract: The object of the present invention is to provide a multilayer phase-change information recording medium comprises a substrate, and N layers of information layer (N represents an integral number of 2 or more), and each of the information layers comprises at least a recording layer in which information is recorded by irradiating laser beam to induce a phase change between crystalline phase and amorphous phase. The present invention is characterized in that when the information layer is disposed so that a first information layer, a second information layer, a third information layer . . .

Abstract: A dual-stack recordable optical data storage medium wherein a focused radiation beam having a wavelength ? enters through an entrance face of the medium during recording. The medium includes a substrate, a first recording stack L0, including a recording layer, the first recording stack L0 having an optical reflection value RL0 and an optical absorption value AL0 at the wavelength ?, and a second recording stack L1 including a recording layer, the second recording stack L1 having an optical reflection value RL1 and an optical absorption value AL1 at the wavelength ?, and a transparent spacer layer between the recording stacks. The second stack is closer to the entrance face than the first stack. By fulfilling the formula AL1?1?Rmin??(Rmin/RL0), where Rmin is the minimum effective optical reflection value for each recording stack, full compatibility is achieved with a read only version of the medium.

Abstract: An optical recording medium and a method for testing that optical recording medium are provided, which can prevent degradation of a reproduction signal in the case where the optical recording medium is stored at a high temperature for a long time, which enables stable recording and reproduction of data before and after the high-temperature storage, and which can achieve high-speed recording and increase of recording density. In the optical recording medium, a reproduction signal output of a recording mark after high-temperature storage that is formed in a recording layer after the optical recording medium is stored at a storage temperature t in a range from 60° C. to 90° C. for at least 50?(4/3)(t?60) hours is 0.9 times or more a reproduction signal output of a recording mark before the high-temperature storage that has the same bit length as the recording mark after the high-temperature storage and is formed before the above high-temperature storage.

Abstract: A write-once optical recording medium and a method and apparatus for recording management information on the recording medium, are provided. The recording medium includes at least one recording layer and SRR information on the recording layer. The SRR information pertains to at least one SRR and includes a header, an SRR entry list, and a terminator. The SRR entry list includes a plurality of SRR entries, each of the SRR entries pertaining to an SRR and including at least one status area for storing therein session start information.

Abstract: Optical information-recording media comprise a first transparent substrate through which a laser beam enters, a first information-recording layer deposited on the first transparent substrate, a first reflection film formed on the first information-recording layer, an intermediate layer deposited on the first reflection film, a second information-recording layer formed on the intermediate layer, a second reflection film deposited on the second information-recording layer, and a second substrate provided on the second reflection film. The recording film of each of the first and second information-recording layers has a main composition represented by (GeTe)xSb2?yInyTe3, and its composition ratio is within ranges of 0.04?y<2 and 4?x?8.

Abstract: A phase-change optical storage medium has a substrate, and a recording layer, to be recorded on which is at least one recorded mark representing information to be recorded by irradiating a recording light beam onto the recording layer in accordance with a recording pulse pattern of recording pulses rising from an erasing power and formed between a recording power larger than the erasing power and a bottom power smaller than the erasing power and of erasing pulses rising from the bottom power to the erasing power. The expressions (1) and (2): 1.00<(R1/R0)<1.15 . . . (1), 1.05<(R9/R0)<1.20 . . .

Abstract: An optical information recording medium of the present invention includes a thin film section made up of one or more thin film, the thin film section being provided on a substrate. Thin films of the thin film section include a single optical multiple interference film which incites optical multiple interference in a thin film section, the optical multiple interference being incited by the change of complex refractive index in accordance with the intensity of incident light. Also, the composition and thickness of the optical multiple interference film are arranged in such a manner as to cause the wavelength distribution of the reflectance of the thin film section at room temperatures to have a minimum value within wavelengths of ±80 nm of the incident light for reproduction. With this, the design freedom of the optical multiple interference film which realizes super-resolution reproduction with a reduced effective reproduction spot is significantly increased.

Abstract: A write retry processing unit repeats a write retry operation of a write and a verify, while performing a setting change of a focus offset for recording a data on an optical storage medium in case a verify error occurs in executing the write and a verify try fails. A learning processing unit retains a sum total of the number of adding times of the successful focus offset and the number of subtracting times of the successful retry offset as a learning result at the successful time of the write retry, and a write condition changing unit changes the focus offset setting value of the default so as to be drawn near to the latest focus offset which succeeds in the retry when the absolute value of the learning result retained in the learning processing unit is equal to or more than a threshold value.

Abstract: A recording medium, and a method and apparatus for recording management information on the recording medium, are provided. According to an embodiment, there is provided a method for recording management information on a recording medium, the method comprising: determining whether recording of padding data in a recordable area of a recordable recording-range of the recording medium is performed, when the recordable recording-range is changed to be a non-recordable recording range; and recording padding indicator information indicating whether the recording of padding data is performed.

Abstract: Plural grooves or lands formed in an information recording carrier include at least a wobbling region and data is recorded wobblingly in this wobbling region by phase shift modulation while recorded digitally with a single or multiple waves as a channel bit.

Abstract: There are provided a mounting unit configured to selectively mount first and second optical disks in which characteristics of recording films are different from one another, and a discriminating unit configured to discriminate which of the first and second optical disks is mounted on the mounting unit based on a level of a reproduction signal which is obtained by reproducing innermost peripheral portion of the first or second optical disk mounted on the mounting unit.

Abstract: An optical information recording medium is provided. This medium at least stores information that indicates a maximum recording linear velocity Vh. The medium comprises a substrate having a concentric circular guide groove. This guide grove has land portions and groves portions. At least a phase change type recording layer is formed on the substrate. The recording layer has such a composition and thickness that a dislocation linear velocity V satisfies the relation V?Vh×0.85.

Abstract: A phase change optical recording medium includes at least a supporting substrate and a recording layer essentially consisting of AgInSbTe alloy compositions implementing recording and readout steps utilizing changes in reflectivity. The recording medium is characterized by the relation v0?0.7 vWH, where the critical relative velocity of phase change, v0, defined by the value of v, at which the differential coefficient, ?dR(v)/dv, reaches a maximum, when the recording medium moves against an optical unit during the recording steps at a relative velocity, v, ranging from minimum and maximum relative velocities warranted for the recording medium, vWL and vWH, respectively. When the reflectivity is measured with varying erase power PE at the linear relative scanning velocity v0, the reflectivity of the recording layer as a function of erase power, R(PE), preferably has a minimum. The recording layer has an activation energy of deterioration equal to or greater than 1.

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: An optical information recording medium includes a plurality of recording layers, a reflectance of at least one of the plurality of the recording layers in a non-initialized state with respect to a light beam for initialization being smaller than a reflectance of the same in an initialized state with respect to the light beam for initialization. The recording layers are initialized by irradiating, among the plurality of recording layers, the recording layer positioned farther from a light beam irradiation side with the light beam prior to irradiating the recording layer positioned closer to the light beam irradiation side, so that the initialized recording layers have no initialization irregularities.

Abstract: The control device (610) controls the recording of data onto an information recording medium where the number of re-writing data onto the same area is limited. The control device (610) determines whether data to be recorded is real-time data or non-real-time data (S1). When it is determined that the data to be recorded is real-time data, the real-time data is recorded in a circular manner onto a second area which is defined in advance within a first area which is assigned in advance on the information recording medium (S2 to S5). When it is determined that the data to be recorded is non-real-time data, the search for an unassigned area is performed from a predetermined address within the first area. The non-real-time data is recorded onto the unassigned area found as a result of the search (S6 and S7). The search for the unassigned area for recording the non-real-time data is also performed in the second area within the first area (S6).

Abstract: A phase-change optical recording medium is disclosed including a supporting substrate and the following contiguous layers formed on the supporting substrate in the order recited such as a first dielectric layer, a recording layer, a second dielectric layer, a metal/alloy layer, and an ultraviolet light curing resinous layer. The recording layer is characterized by its uppermost recrystallization linear velocity ranging from about 5.0 m/sec to about 10.0 m/sec, which can be utilized in read/write/erase operations for the recording medium at linear velocities higher than the quad-speed as well.

Abstract: An information recording medium according to the present invention includes a plurality of recording layers, and a test area for determining a recording power of a laser light for each of the plurality of recording layers, in which a first test area of a first layer and a second test area of a second layer adjacent to the first layer are provided at different radial positions.

Abstract: An optical recording medium including two or more recording layers which are capable of transmitting at a high transmittance recording light or reproducing light for performing recording/reproducing of a first recording layer (3) without having to make the thickness of a second recording film (5) positioned towards the side from which the recording light or the reproducing light enters. An optical recording medium including two or more recording layers, and which includes the first recording layer (3), the second recording layer (5) positioned further towards, with an intermediate layer (4) in between, the side from which the recording light or the reproducing light enters than is the first recording layer (3), and includes, between the above-mentioned intermediate layer (4) and the above-mentioned second recording layer (5), a dielectric layer (7) for increasing the transmittance for light passing through the above-mentioned second recording layer as the incident angle of the light becomes greater.

Abstract: Plural grooves or lands formed in an information recording carrier include at least a wobbling region and data is recorded wobblingly in this wobbling region by phase shift modulation while recorded digitally with a single or multiple waves as a channel bit.

Abstract: Phase-change type, reversible optical information recording medium, being possible for recording, reproducing, erasing, and rewriting of information, by use of a laser beam. This invention, consists of recording thin film of ternary elements, for example, containing Ge, Te, Sb/or Bi or quaternary elements containing the fourth element of Se with which a part of Te is replaced, which is established on such surface—flat substrates as glass or plastics. In this case, the component ratio of Te and Se is selected not to be excess for other elements, such as Ge, Sb/or Bi so as to be fixed as stable compounds of stoichiometric compositions of GeTe, Sb2Te3/or Bi2Te3, or GeSe, Sb2Se3/Bi2Se3 when crystallized. Strictly speaking, a concentration of each component is selected to have proper ratio of the number of atoms each other so as to represent whole composition as the sum of each component. By this treatment, it is possible to have high crystallization speed and long cyclability of recording/erasing.