Abstract: The disk-shaped information recording medium having an outer diameter and an inner diameter comprises a substrate having a predetermined thickness, a first side that is one side of the substrate, a second side that is the other side of the substrate, a cylindrical portion forming a through hole formed at a center of the substrate, and a thin portion formed so as to surround an outer diameter of the cylindrical portion. The thin portion is thinner than the predetermined thickness and includes a non-inclined surface and an inclined surface formed on an outer diameter side of the non-inclined surface. The inclined surface is inclined at an angle greater than or equal to 25 degrees and less than or equal to 35 degrees with respect to the non-inclined surface.
Abstract: The disk-shaped information recording medium having an outer diameter and an inner diameter comprises a substrate having a predetermined thickness, a first side that is one side of the substrate, a second side that is the other side of the substrate, a cylindrical portion forming a through hole formed at a center of the substrate, and a thin portion formed so as to surround an outer diameter of the cylindrical portion. The thin portion is thinner than the predetermined thickness and includes a non-inclined surface and an inclined surface formed on an outer diameter side of the non-inclined surface. The inclined surface is inclined at a predetermined angle to the non-inclined surface and is larger than the non-inclined surface in the thin portion.
Abstract: A recording medium is provided with: a guide layer on which a guide track or tracks are formed; and a plurality of recording layers, wherein a same mark group is formed in a same rotational phase position of each of a plurality of guide tracks which are included in a beam spot of guide laser light, the mark group including a pair of record marks which are shifted by a predetermined distance toward a right side and a left side, respectively, from a track center.
Type:
Grant
Filed:
January 22, 2013
Date of Patent:
November 4, 2014
Assignees:
Pioneer Corporation, Memory-Tech Holdings Inc.
Abstract: An optical information recording medium 10 comprises: a plurality of recording layers 14, each of which undergoes a change in a refractive index by irradiation with a recording beam; and at least one intermediate layer 15 provided between the plurality of recording layers 14. The recording layer 14 and the intermediate layer 15 have different refractive indices, and, among interfaces between the plurality of recording layers 14 and the at least one intermediate layer 15, a recording layer 14 and an intermediate layer 15 disposed adjacent to the recording layer 14 at an incident side from which the recording beam enters the recording layer 14 are merged with each other at an interface (near-side interface 19) therebetween, whereby a refractive index gradually changes at the interface.
Abstract: A radio frequency transponder for use with a disc, such as a CD or DVD has an antenna formed by depositing a conductive solution on a surface of disc outside at adjacent to its outer periphery outside of the disc storage area to yield at least one conductive region. A transponder circuit is coupled to the antenna for supplying an RF signal to the antenna in response to a signal received from the antenna.
Abstract: A manufacturing method of an optical information recording medium includes forming a substrate which has a first main surface and a second main surface, forming a first information signal layer on the first main surface of the substrate, forming an intermediate layer on the first information signal layer, forming a second information signal layer on the intermediate layer, irradiating light from the second main surface side of the substrate and recording identification information on a first region out of the first region and a second region, and forming a barrier layer with regard to the second main surface in the second region which excludes the first region where the identification information is recorded before the recording of the identification information.
Abstract: An apparatus for storing digital media utilizes an electrically conductive element, which is for reading stored digital media, and multiple electrically conductive resonant circuits as an antenna for radio frequency communications. Each of the resonant circuits is electrically isolated from the other resonant circuits and the electrically conductive element is electrically isolated from each of the resonant circuits. As a result, the apparatus for storing digital media has a relatively wide operating frequency range and a relatively long communications range, which allows worldwide usage in various applications. For example, an optically readable compact disk (CD) utilizes a metal layer configured as a reflective surface for reading stored digital media in the CD, an electrically conductive component that is not in contact with a radio frequency identification (RFID) integrated circuit (IC), and an electrically conductive component that is in contact with the RFID IC, as an antenna for the RFID IC.
Abstract: An optical recording medium is provided. The optical recording medium includes a multilayer including an N (N?5) number of interfaces capable of reflecting incident light.
Type:
Grant
Filed:
March 11, 2011
Date of Patent:
October 22, 2013
Assignee:
Sony Corporation
Inventors:
Tetsuhiro Sakamoto, Hirotaka Miyamoto, Jun Nakano, Kouichi Yasuda
Abstract: A system and method are described for rendering Compact Discs (CDs) and Digital Video Discs (DVDs) unreadable. Embodiments comprise a frame, a guide for constraining motion of the frame with respect to a disc, and at least one scraping element. Scraping elements may be positioned to damage the disc volume descriptor while the frame moves in a constrained manner relative to the disc. The guide may comprise a spindle which engages the center hole of a disc to hold the frame in a radially-fixed position. A scraping element on the frame damages the disc as the disc rotates relative to the frame. The guide may be integrated, such that the frame comprises a slot through which the disc passes. A scraping element inside the slot damages a disc as it passes through. Embodiments are hand operated, not motorized, and some have no moving parts. Embodiments also function with non-optical media.
Abstract: An optical article comprising a plurality of optically detectable marks disposed on a surface of the optical article; a removable electrical device disposed on the surface of the optical article; wherein the electrical device is operatively coupled to the optical article; and wherein the electrical device is configured to interact with an activation signal when brought in direct contact with a communication device that applies the activation signal to the electrical device. A removable electrical device is also provided. A system and a method for activation are also provided.
Type:
Grant
Filed:
May 13, 2008
Date of Patent:
June 25, 2013
Assignee:
NBCUniversal Media, LLC
Inventors:
Marc Brian Wisnudel, John Erik Hershey, James Enrico Sabatini, William Richard Mandel, Clayton Young, Matthew Jeremiah Misner, Kasiraman Krishnan, Kaustubh Ravindra Nagarkar
Abstract: The present invention relates to a recordable optical record carrier for recording information using a radiation beam having wavelength ? and incident on an entrance surface of the optical record carrier comprising, in this order: a protective layer facing the entrance surface; first recording stack (L0), the recording stack comprising a recording layer of an organic dye material and a groove structure; a transparent spacer layer sandwiched between the neighboring recording stacks; and a second recording stack (LN) comprising a recording layer, wherein the groove depth of the recording layer of the first recording stack (L0) is in a range from 0.241*?/nS to 0.362*?/nS, where nS is a refractive index of a material in a land between grooves on the groove structure.
Abstract: The subject innovation relates to systems and/or methodologies for using randomly positioned electromagnetic scatterers deposited into a predetermined region of an optical storage medium (e.g., Blue Ray DVD, HD DVD, CD, etc.) as a distinct three dimensional (3D) hard-to-copy digital rights management feature. A scatterers' topology is scanned using a matrix of antennas that sense the scatterers' electromagnetic response as the optical disc revolves at near-constant angular speed. The response, f, called an RF fingerprint, is then concatenated with an arbitrary text, t, that defines the digital rights management information imposed by the disk publisher.
Type:
Grant
Filed:
February 3, 2009
Date of Patent:
June 18, 2013
Assignee:
Microsoft Corporation
Inventors:
Darko Kirovski, Gerald Reuben DeJean, Barry C. Bond, Sebastian Lange
Abstract: Provided is a pattern transfer medium manufacturing apparatus including a disc injection compression molding unit that forms a disc-shaped pattern transfer medium by an injection compression molding using a disc molding die and a disc-shaped stamper and a cutting unit that performs cutting the periphery of a concave and convex pattern portion on the disc-shaped pattern transfer medium, which is formed due to a transfer by the injection compression molding, as a target object.
Type:
Application
Filed:
November 13, 2012
Publication date:
May 30, 2013
Applicants:
SONY DADC CORPORATION, SONY CORPORATION
Inventors:
Sony Corporation, Sony DADC Corporation
Abstract: In embodiments of the present invention improved capabilities are described for serving a computer game, comprising: (a) providing two separate storage facilities accessible from a server, the first storage facility comprising fast response searchable memory for storage of recently produced game play data, and the second storage facility comprising a structured database for longer term storage of game play data, the first memory having a data search and data retrieval speed that is substantially faster than the second memory; (b) receiving, at the server, a game play request from a live gaming participant with a desired opponent attribute; (c) in response to the game play request, searching the first memory, based on the attribute, to identify prior game play data corresponding to an appropriate opponent; and (d) presenting a multi-player game environment where the live gaming participant can play against and have two-way interactions with an apparently live opponent.
Abstract: A disc has an outer section on which digital media can be recorded and a core in its center in which a flash memory is embedded with the core having a central hole and electrical contacts to the flash memory. A disc drive has a drive spindle that is to extend into the disc core central hole with one of the spindle or spindle hub having electrical contacts to engage with the core electrical contacts so that data can be written into and/or read from the core flash memory by electronic components of the drive.
Type:
Grant
Filed:
June 27, 2012
Date of Patent:
April 23, 2013
Assignee:
International Business Machines Corporation
Abstract: A disc has an outer section on which digital media can be recorded and a core in its center in which a flash memory is embedded with the core having a central hole and electrical contacts to the flash memory. A disc drive has a drive spindle that is to extend into the disc core central hole with one of the spindle or spindle hub having electrical contacts to engage with the core electrical contacts so that data can be written into and/or read from the core flash memory by electronic components of the drive.
Type:
Grant
Filed:
June 19, 2012
Date of Patent:
April 16, 2013
Assignee:
International Business Machines Corporation
Abstract: A medium in which information is recorded has: a guide layer of one or two layers each having a spiral track added with address information; and a plurality of recording layers in which depth positions from the guide layer differ. A user data area, spare areas, and a management information storage area for storing information about use of the spare areas are included in each of the plurality of recording layers. An inner peripheral spare area locating on an inner peripheral side of the user data area is configured so as to be used to record the information from an outer peripheral direction toward an inner peripheral direction, and an outer peripheral spare area locating on an outer peripheral side of the user data area is configured so as to be used to record the information from the inner peripheral direction toward the outer peripheral direction.
Abstract: In a system for reproducing AV information from a recording medium, such as a DVD, not only are usual titles reproduced, but also related information relevant to specific stream information is acquired easily by making use of resources on a computer network. In a reproducing system with the function of reproducing the title information recorded on a DVD and displaying it on the screen of a display section, when the user clicks a Web mark on the screen, the CPU links to a Web server on the Internet via a modem and accesses the Web page related to the stream information on the screen. At that time, the related Web page is the selected information conforming to parental information, or attribute information, set in the system.
Abstract: An information recording medium excellent in long storage and capable of high-density recording, method of manufacturing the information recording medium, and information recording material are provided. Pulse laser light is focused onto a recording layer in which a thermosetting epoxy resin having a skeleton with high planarity and a curing agent are polymerized to form a recording mark. With a molecular weight between cross-linking points of a cured material of the recording layer being set to be equal to or smaller than 2000 and, more preferably, equal to or smaller than 500, a distance between recording marks (cavities) can be shortened.
Type:
Application
Filed:
June 9, 2011
Publication date:
February 28, 2013
Applicant:
Sony Chemical & Information Device Corporation
Abstract: An information recording medium excellent in long storage and capable of high-density recording, method of manufacturing the information recording medium, and information recording material are provided. Pulse laser light is focused onto a recording layer in which a thermosetting epoxy resin having a skeleton with high planarity and a curing agent are polymerized to form a recording mark. With a cured material of a recording layer having a density equal to or larger than 1.210 g/cm3 and a glass transition temperature of 110° C. to 140° C., high-speed recording is possible.
Type:
Application
Filed:
June 9, 2011
Publication date:
January 17, 2013
Applicant:
Sony Chemical & Information Device Corporation
Abstract: An optical recording medium is provided. The optical recording medium includes a multilayer including an N (N?5) number of interfaces capable of reflecting incident light.
Type:
Application
Filed:
March 11, 2011
Publication date:
January 3, 2013
Applicant:
SONY CORPORATION
Inventors:
Tetsuhiro Sakamoto, Hirotaka Miyamoto, Jun Nakano, Kouichi Yasuda
Abstract: In a multilayer optical disc having information layers conforming to a plurality of different optical disc standards, because the type of each information layer is not recorded in the other information layers, every time the information layer being accessed changes, it has been necessary to read the type of the information layer and select a method of generating a tracking error signal adapted to the type of information layer, so access has taken time. In order to solve the above problem, in the optical multilayer disc according to the present invention, having information layers conforming to a plurality of different optical disc standards, in an area in one of the information layers, information about the other information layers is recorded. The time required to access the other information layers can be reduced by using this information to select a tracking error signal generating method.
Abstract: A small form factor disc drive is structured to hold and play an optical data storage disc measuring approximately 32 mm in diameter and containing 1 GB of data per layer. The disc drive contains a blue wavelength laser, an objective lens having a numerical aperture in the range of 0.70-0.78 and conventional DVD-compatible controller electronics. This unique combination of elements allows a full-length movie or a video game to be displayed with DVD-quality on a cell phone or other portable hand held device.
Type:
Grant
Filed:
November 24, 2008
Date of Patent:
November 20, 2012
Assignee:
VMO Systems Inc.
Inventors:
Jerry E. Hurst, Jr., Neil Deeman, Steven B. Volk
Abstract: An information recording medium is 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, and a light transmitting 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, 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. Auxiliary information and a reference clock is recorded alternately. Information is recorded in the recording layer corresponding to a land portion by either one change of reflectivity difference and refractive index difference in the recording layer.
Abstract: There is herein described a Transmedian Storage and Transfer Device (TSTD) that will provide a more useful system for information storage, retrieval, and computation. This is achieved by increasing the speed and storage capacity beyond that provided by existing computers and related systems. To obtain these benefits, the TSTD utilizes a spherical surface for information storage along with a system detector that can be point-like, line-like, or spherical. Further more, multiple spheres can be incorporated into the TSTD thus resulting in a sphere matrix.
Abstract: The recording medium 100 stores playlist information and a plurality of elementary streams. The playlist information includes a basic stream selection table and an extension stream selection table. The basic stream selection table shows elementary streams that are permitted to be played back in a monoscopic playback mode. The extension stream selection table shows elementary streams that are permitted to be played back only in a stereoscopic playback mode. The stream entry in the extension stream selection table indicates a packet identifier that is to be used by the playback device to perform demultiplexing when the playback device is in the stereoscopic playback mode and the corresponding stream number is set in the stream number register provided in the playback device.
Abstract: A disc has an outer section on which digital media can be recorded and a core in its center in which a flash memory is embedded with the core having a central hole and electrical contacts to the flash memory. A disc drive has a drive spindle that is to extend into the disc core central hole with one of the spindle or spindle hub having electrical contacts to engage with the core electrical contacts so that data can be written into and/or read from the core flash memory by electronic components of the drive.
Type:
Grant
Filed:
January 4, 2008
Date of Patent:
July 31, 2012
Assignee:
International Business Machines Corporation
Abstract: An optical disk having a recording layer on a substrate, a bonding layer which is made of an ultraviolet cured resin bonding the recording layer, a transparent layer which is bonded to the bonding layer, and an overcoating layer which is formed on the transparent sheet and is made of the ultraviolet cured resin further has a mixed layer which is formed by mixing the ultraviolet cured resins of the bonding layer and the overcoating layer. Consequently, the bonding layer, the overcoating layer, and the mixed layer are integrally cured, so that the substrate is entirely covered with the ultraviolet cured resin having transparency, which allows a light transmitting layer A to be protected with sufficient strength.
Abstract: Embodiments of methods and systems for controlling access to information stored on memory or data storage devices are disclosed. In various embodiments, methods of retrieving information from a data storage device previously deactivated by modification or degradation of at least a portion of the data storage device are disclosed.
Abstract: Embodiments of methods and systems for controlling access to information stored on memory or data storage devices are disclosed. In various embodiments, methods of retrieving information from a data storage device previously deactivated by modification or degradation of at least a portion of the data storage device are disclosed.
Abstract: A guide-layer separated optical recording medium includes a guide layer with a guide track formed therein and a plurality of recording layers, these layers being separately deposited from each other. A layer position information region for indicating position information of each of the recording layers, is formed on the guide track within a different range of the guide layer for each of the recording layers. Each of the recording layers includes a preformat region having a predetermined signal written on a record track along the guide track, and the preformat region on each of the recording layers is provided in a region corresponding to the layer position information region. An optical recording medium drive apparatus and a recording layer access method for the guide-layer separated optical recording medium are also provided.
Abstract: An optical disk having a recording layer on a substrate, a bonding layer which is made of an ultraviolet cured resin bonding the recording layer, a transparent layer which is bonded to the bonding layer, and an overcoating layer which is formed on the transparent sheet and is made of the ultraviolet cured resin further has a mixed layer which is formed by mixing the ultraviolet cured resins of the bonding layer and the overcoating layer. Consequently, the bonding layer, the overcoating layer, and the mixed layer are integrally cured, so that the substrate is entirely covered with the ultraviolet cured resin having transparency, which allows a light transmitting layer A to be protected with sufficient strength.
Abstract: The optical storage medium comprises a substrate layer and a data layer disposed on the substrate layer, the data layer having a mark/space data structure being arranged in tracks, wherein on a first track, the marks are enlarged in length and the spaces are shortened in length, and on an adjacent track, the marks are shortened in length and the spaces are enlarged in length. The track pitch between adjacent tracks is particularly below a diffraction limit of ?/2*NA of a pickup for reading of the data.
Type:
Application
Filed:
April 26, 2010
Publication date:
May 17, 2012
Inventors:
Gael Pilard, Herbert Hoelzemann, Alois Kern, Frank Przygodda, Stephan Knappmann
Abstract: To provide an information recording medium which is capable of reducing damage to a recording layer while improving environmental resistance of the recording layer and which enables information to be recorded or reproduced at a high density and a high sensitivity, an optical information recording and reproducing apparatus, an optical information recording and reproducing method, and a manufacturing method of an information recording medium.
Abstract: The multilayer optical recording medium with six or more recording and reading layers disposed one above the other has at least two or more recording and reading layer groups. The recording and reading layer groups each include a plurality of recording and reading layers successively disposed one above the other. The reflectance of each of the recording and reading layers in a stacked state decreases in the order from a front side near a light incident surface toward a back side far from the light incident surface. A recording and reading layer nearest the front side among the recording and reading layers in the recording and reading layer group nearer the back side has a reflectance in a stacked state higher than that of a recording and reading layer nearest the back side among the recording and reading layers in the recording and reading layer group nearer the front side.
Abstract: The multilayer optical recording medium with at least four or more recording and reading layers disposed one above the other has at least two or more recording and reading layer groups each including the recording and reading layers successively disposed one above the other. In adjacent recording and reading layer groups with an intermediate layer interposed therebetween, a recording and reading layer nearest a front side in the recording and reading layer group nearer a back side is higher than the higher value of the reflectances in a stacked state of two recording and reading layers nearest the back side in the recording and reading layer group nearer the front side.
Abstract: Simple design of a multilayer optical recording medium is achieved while suppressing interlayer crosstalk and confocal crosstalk in the multilayer optical recording medium. Simple recording and reading control by a recording and reading unit is also achieved. The multilayer optical recording medium includes at least three or more recording and reading layers deposited one above the other with intermediate layers interposed therebetween, and information can be read by light irradiation from the layers. The intermediate layers have film thicknesses of two types or less, and all the recording and reading layers except the recording and reading layer farthest from a light incident surface have substantially the same optical constant.
Abstract: An optical recording medium includes a recording layer in which recording of a mark is selectively performed in a depth direction by irradiation of first light, and the mark is formed in multilayer form; and a reflection film reflecting second light of a wavelength different from a wavelength of the first light, and provided on a lower layer side of the recording layer.
Abstract: An optical recording medium is provided having a plurality of laminated recording layers, wherein the recording layers are formed such that a spacing between each pair of recording layers of all recording layer combinations selected from the plurality of recording layers is different from that of each other pair. Accordingly, a return of lights reflected by other layers to an optical head along the same optical path as reflected light from a readout layer during the reproduction can be avoided. Therefore, use of the optical recording medium, from which a good reproduction signal can be obtained, can suppress a deterioration of a servo signal and a reproduction signal of a reproducing device due to a variation of interference fringes on a light receiving element.
Abstract: An apparatus for storing digital media utilizes an electrically conductive element, which is for reading stored digital media, and multiple electrically conductive resonant circuits as an antenna for radio frequency communications. Each of the resonant circuits is electrically isolated from the other resonant circuits and the electrically conductive element is electrically isolated from each of the resonant circuits. As a result, the apparatus for storing digital media has a relatively wide operating frequency range and a relatively long communications range, which allows worldwide usage in various applications. For example, an optically readable compact disk (CD) utilizes a metal layer configured as a reflective surface for reading stored digital media in the CD, an electrically conductive component that is not in contact with a radio frequency identification (RFID) integrated circuit (IC), and an electrically conductive component that is in contact with the RFID IC, as an antenna for the RFID IC.
Abstract: Provided is an optical disc in which at least a light reflecting layer and a light transmitting layer that includes a cured film of an ultraviolet curable composition are stacked on a substrate, and information is reproduced by making a blue laser beam be incident on the optical disc from a side of the light transmitting layer, wherein an elastic modulus (25° C.) measured by indenting a Vickers indenter having a vertex angle of 136° under a load of 100 mN into a surface of the cured film of the ultraviolet curable composition is 1,500 MPa or less; and a loss modulus (E?) at 60° C. in a dynamic viscoelastic spectrum of the cured film measured at a frequency of 3.5 Hz is 10 MPa or less. Thus, warpage is reduced during curing and plastic deformation is less likely even under a load for a long period of time.
Type:
Application
Filed:
September 1, 2009
Publication date:
March 8, 2012
Applicant:
DIC Corporation
Inventors:
Atsushi Oshio, Junji Yamaguchi, Daisuke Ito
Abstract: According to one embodiment, an information storage medium includes an organic dye material which records information with a light beam having a wavelength equal to or smaller than 620 nm.
Type:
Grant
Filed:
November 29, 2006
Date of Patent:
February 28, 2012
Assignee:
Kabushiki Kaisha Toshiba
Inventors:
Hideo Ando, Seiji Morita, Koji Takazawa
Abstract: A super-resolution optical information recording medium comprises a super-resolution layer and a recording layer which are laminated on a support substrate, wherein the super-resolution layer is provided with properties consisting of a first state to maintain a solid phase against irradiation of a laser beams, and a second state to become a liquid layer state against irradiation of a laser beam onto a recording mark on the recording layer to thereby change an optical constant. The optical constant is determined so that a ratio of a super-resolution signal intensity obtained at a second state region against a background light interference intensity obtained at a first state region is at least 1.8, and a ratio of the super-resolution signal intensity obtained at the second state region against a disk noise intensity obtained at first and second state regions is at least 0.16.
Abstract: According to one embodiment, an information storage medium includes an organic dye material which records information with a light beam having a wavelength equal to or smaller than 620 nm.
Type:
Application
Filed:
September 15, 2011
Publication date:
January 12, 2012
Inventors:
Hideo ANDO, Seiji MORITA, Koji TAKAZAWA
Abstract: According to one embodiment, an information storage medium includes an organic dye material which records information with a light beam having a wavelength equal to or smaller than 620 nm.
Type:
Application
Filed:
September 15, 2011
Publication date:
January 12, 2012
Inventors:
Hideo ANDO, Seiji MORITA, Koji TAKAZAWA
Abstract: According to one embodiment, an information storage medium includes an organic dye material which records information with a light beam having a wavelength equal to or smaller than 620 nm.
Type:
Application
Filed:
September 15, 2011
Publication date:
January 5, 2012
Inventors:
Hideo ANDO, Seiji Morita, Koji Takazawa
Abstract: According to one embodiment, an information storage medium includes an organic dye material which records information with a light beam having a wavelength equal to or smaller than 620 nm.
Type:
Application
Filed:
September 15, 2011
Publication date:
January 5, 2012
Inventors:
Hideo ANDO, Seiji Morita, Koji Takazawa
Abstract: The optical disc comprises a substrate layer, a read-only data layer having a pit/land data structure with an average pit width, arranged in tracks on the substrate layer, and a nonlinear layer with a super-resolution structure disposed on the data layer, wherein a super-resolution pit following a super-resolution land and a preceding diffractive pit is enlarged in width with regard to the average pit width, and a diffractive pit preceding a super-resolution land and a subsequent super-resolution pit is reduced in pit width with regard to the average pit width.
Abstract: An object of the present invention is to provide a marking forming apparatus, a method of forming a laser marking on an optical disk, a reproduction apparatus, an optical disk, and a method of manufacturing an optical disk, capable of providing a greatly improved copy prevention capability as compared to prior known construction. To achieve this object, in the optical disk of the invention, for example, a marking is formed by a laser on a reflective film of a disk holding data written thereon and at least position information of the marking or information concerning the position information is written on the disk in an encrypted form or with a digital signature appended thereto.
Abstract: An optical recording medium has a user data area and a lead-out area, wherein the user data area and the lead-out area each has grooves and lands formed thereon. Wobbles are formed on at least one lateral surface of grooves of the user data area and the lead-out area, and configured such that wobble characteristics are made different between the user data area and the lead-out area. Different types of wobbles are formed on the grooves of either the user data area or the lead-out area, thereby preventing an optical pickup that performs recording/reproduction from deviating from the user data area. Also, in a multi-layer optical recording medium, a whole area of a recording layer is configured to have a same condition, thereby preventing deterioration in reproduction and/or recording due to a difference in light power transmittance of another recording layer.